This is the accepted version of the article:
Matamales Andreu, Rafel; Roig Munar, Francesc X.; Oms, O.; [et al.]. «A
captorhinid-dominated assemblage from the palaeoequatorial Permian of Menorca
(Balearic Islands, western Mediterranean)». Earth and Environmental Science
Transactions of the Royal Society of Edinburgh, Vol. 112, Issue 2 (June 2021),
p. 125-145. DOI 10.1017/S1755691021000268


This version is available at https://ddd.uab.cat/record/250385

under the terms of the            license
     A captorhinid-dominated assemblage from the palaeoequatorial Permian of Menorca
                           (Balearic Islands, western Mediterranean)



    Rafel Matamales-Andreu1,2*, Francesc Xavier Roig-Munar3, Oriol Oms4, Àngel Galobart1,5 &
                                          Josep Fortuny1



1
    Institut Català de Paleontologia Miquel Crusafont, Universitat Autònoma de Barcelona, Edifici
ICTA-ICP, c/ Columnes s/n, Campus de la UAB, 08193 Cerdanyola del Vallès, Barcelona, Spain.

2
    Museu Balear de Ciències Naturals, ctra. Palma-Port de Sóller km 30, 07100 Sóller, Mallorca,
Illes Balears, Spain.

3
    C/ Carritxaret 18-6, 07749 es Migjorn Gran, Menorca, Illes Balears, Spain.

4
    Departament de Geologia, Universitat Autònoma de Barcelona, avda. de l’Eix Central s/n,
Campus de la UAB, 08193 Cerdanyola del Vallès, Barcelona, Spain.

5
    Museu de la Conca Dellà, c/ del Museu 4, 25650 Isona i Conca Dellà, Lleida, Spain.

*Corresponding author. E-mail address: rafel.matamales@icp.cat.
Abstract

Moradisaurine captorhinid eureptiles were a successful group of high-fibre herbivores that lived
in the arid low latitudes of Pangaea during the Permian. Here we describe a palaeoassemblage
from the Permian of Menorca (Balearic Islands, western Mediterranean), consisting of ichnites of
small captorhinomorph eureptiles, probably moradisaurines (Hyloidichnus) and parareptiles (cf.
Erpetopus), and bones of two different taxa of moradisaurines. The smallest of the two is not
diagnostic beyond Moradisaurinae incertae sedis. The largest one, on the other hand, shows
characters that are not present in any other known species of moradisaurine (densely ornamented
maxillar teeth), and it is therefore described as Balearosaurus bombardensis gen. et sp. nov. Other
remains found in the same outcrop are identified as cf. Balearosaurus bombardensis gen. et sp.
nov., as they could also belong to the newly-described taxon. This species is sister to the
moradisaurine from the lower Permian of the neighbouring island of Mallorca, and is also closely
related to the North American genus Rothianiscus. This makes it possible to suggest the
hypothesis that the Variscan mountains, which separated North America from southern Europe
during the Permian, were not a very important palaeobiogeographical barrier to the dispersion of
moradisaurines. In fact, mapping all moradisaurine occurrences known so far, it is shown that
their distribution area encompassed both sides of the Variscan mountains, essentially being
restricted to the arid belt of palaeoequatorial Pangaea, where they probably outcompeted other
herbivorous clades until they died out in the late Permian.



Key Words: Captorhinidae, Moradisaurinae, Hyloidichnus, palaeobiogeography, central
Pangaea
Captorhinids were a clade of small to medium-sized early eureptiles that became widespread on
Laurasia and Gondwana during the Permian. The earliest known member of the group, of small
size and with a single-rowed dentition well suited for insectivory, lived in North America during
the late Carboniferous (Müller & Reisz 2005; Reisz et al. 2016). Captorhinids radiated during the
early Permian, maintaining small forms with a single row of teeth that likely fed on insects or
even on smaller tetrapods (e.g., Brocklehurst 2017; Modesto et al. 2018 and references therein),
which coexisted with other small to medium-sized forms that developed other food processing
styles. Some of those species were omnivorous, with teeth arranged in a single row or with several
rows of teeth oblique to the jaw margins (Modesto et al. 2007; LeBlanc & Reisz 2015;
Brocklehurst 2017; Reisz et al. 2020), whereas others were high-fibre herbivores, always with
multiple rows of teeth arranged more or less parallel to the jaw margins (Dodick & Modesto 1995;
Reisz & Sues 2000; Modesto et al. 2014, 2019; LeBlanc et al. 2015; Brocklehurst 2017). This
last group has been classified in a subfamily of their own, the Moradisaurinae Ricqlès & Taquet,
1982.

        Moradisaurines showed a wide range of sizes, from very small species with a skull length
of about 25 mm (Olson 1970), to medium-sized species with a skull length of about 450 mm
(Ricqlès & Taquet 1982; Modesto et al. 2019). All of them possessed tooth plates with several
tooth rows on the dentary and on the maxilla, well suited for high-fibre herbivory (e.g., Dodick
& Modesto 1995; Reisz & Sues 2000; LeBlanc et al. 2015). In fact, some representatives of both
small and medium-sized forms have been inferred to be able to produce a propalinal motion of
the lower jaw during food processing (Dodick & Modesto 1995; Modesto et al. 2007, 2014, 2019),
which enabled them to efficiently grind and shred the plant material on which they fed. The
number of rows and teeth per row were variable among the different species and throughout
ontogeny (e.g., LeBlanc & Reisz 2015; Jung & Sumida 2017; Modesto et al. 2019). In the largest
forms, the limb bones became distinctly more robust (e.g., Modesto et al. 2019), but not as much
as theoretically expected (Romano & Rubidge 2019). In order to reduce the mechanical stress on
the limb bones during locomotion, those herbivorous large forms probably moved more slowly
(Romano & Rubidge 2019), which did not compromise their ability to obtain plant food,
contrarily to smaller captorhinids, which needed to catch their prey.

        Ichnites attributed to captorhinomorphs that could be produced by moradisaurines,
corresponding to the ichnogenus Hyloidichnus Gilmore, 1927, first appear in Sakmarian rocks
(lower Permian) of North America (Lucas et al. 2013; Schneider, 2020), slightly earlier than the
oldest known moradisaurines, which belong to the genus Captorhinikos Olson, 1954, reported
from the Artinskian to the middle Kungurian (lower Permian) of North and South America
(Cisneros et al. 2020a and references therein). The genus Captorhinikos is currently considered
the most basal member and the first high-fibre herbivore of the clade (Brocklehurst 2017;
Modesto et al. 2019). Larger herbivorous species started to appear shortly after, represented by
the genera Labidosaurikos Stovall, 1950 (Kungurian, lower Permian: Dodick & Modesto 1995),
Kahneria Olson, 1962a (Kungurian/Roadian?, lower/middle Permian: Olson 1962a) and
Rothianiscus Kuhn, 1961 (Kungurian/Roadian?, lower/middle Permian: Olson 1962a), together
with other undetermined specimens from southern North America (Kungurian, lower Permian:
Modesto et al. 2016) and Mallorca (Artinskian–Kungurian?, lower Permian: Liebrecht et al.
2017; Matamales-Andreu et al. 2019). This also coincided with an increase in morphological
disparity (Brocklehurst 2017), which may have played a part in the ecological success of the
group, contributing to the shift to eureptile dominance in the post-Artinskian ichnoassemblages
of both Europe and North America (Marchetti et al. 2015a, 2019a). There, the ichnogenus
Hyloidichnus becomes abundant, and in rare cases, it is accompanied by another ichnogenus
purportedly produced by large moradisaurines, Merifontichnus Gand et al., 2000 (Gand & Durand
2006; Marchetti 2016; Citton et al. 2019; Santi et al. 2020). In the middle–late Permian,
moradisaurines appear represented by small-sized species in eastern Europe (Gecatogomphius
Vjushkov & Chudinov, 1957, middle Permian: Ivakhnenko 2008), central-east Asia (Gansurhinus
Reisz et al., 2011, middle–upper Permian: Reisz et al. 2011) and North Africa (Acrodenta Dutuit,
1976, and other unidentified moradisaurines, upper? Permian: Jalil & Dutuit 1996; Hmich et al.
2006), and the largest known species, in central Africa (Moradisaurus Taquet, 1969, middle–
upper? Permian: Olroyd & Sidor 2017; Modesto et al. 2019). The most recent ichnites attributed
to moradisaurines belong to the ichnogenus Hyloidichnus and were found in upper Permian rocks
of North Africa (Voigt et al. 2010).

        As evidenced by some of the works cited above, the record of body fossils of
moradisaurine captorhinid eureptiles in southern Europe was hitherto restricted to the island of
Mallorca (Balearic Islands, western Mediterranean). Liebrecht et al. (2017) described a fragment
of maxilla and parts of the palate of a large moradisaurine, which confirmed the presence of this
clade on the island, previously inferred from tracks (Calafat et al. 1986, 1986–1987; Calafat 1988;
Gand et al. 2010; Matamales-Andreu et al. 2019). Both the bones and the tracks were found in
the Port des Canonge Unit, the age of which is at present unclear and under study, preliminarily
dated as lower Permian (Artinskian or Kungurian) (Matamales-Andreu et al. 2019). Nevertheless,
from the Permian beds of the neighbouring island of Menorca, some authors (Pretus & Obrador
1987; Carmona 2004) had also reported large bones of unidentified tetrapods, which had not been
studied in detail so far.

        The first report of vertebrate remains on Menorca was published by Pretus & Obrador
(1987), illustrating a large scapula found ex situ. That and other bones, herein revised, were the
object of the preliminary work of Carmona (2004), who suggested that two of the fossil vertebrae
belonged to a large and a small species of indeterminate seymouriamorphs. However, it is worth
noting that Carmona (2004) did not consider all the bones that had been collected until then,
because some of them had yet to be prepared.

          The present work resumes the study of tetrapod bone remains from the Permian of Cala
del Pilar–Pla de Mar section (Menorca, Balearic Islands, western Mediterranean), re-assigning all
of them to moradisaurine captorhinid eureptiles. This includes the detailed description of all the
material present in old collections except for the scapula figured by Pretus & Obrador (1987),
which is currently housed in a private collection and preparation required to properly study it has
not been possible. Moreover, new ichnological material found at the outcrop is also studied.
Unfortunately, new prospection/excavation campaigns have not been carried out due to
administrative setbacks. Nevertheless, this study aims to shed light on the hitherto poorly
described tetrapod fossils of this site, characterising a new locality of Permian palaeoequatorial
faunas.




1. Geological and geographical context

Menorca is the northeasternmost island of the Balearic Archipelago, located at the western
Mediterranean. Even as an extension towards the NE of the Betic Orogen, Menorca is quite
different from the rest of the Balearic Islands in structural and stratigraphic terms (Bourrouilh
1973; Vera et al. 2004; Sàbat et al. 2018). Geologically, the island is neatly divided into two main
regions: Migjorn, at the S, where a post-orogenic upper Miocene cover is largely dominant; and
Tramuntana, at the N, with older materials that broadly span from the Lochkovian (Lower
Devonian) to the Rupelian (lower Oligocene) (Bourrouilh 1973, 1983; Vera et al. 2004; Martin-
Closas & Ramos 2005) (Fig. 1A). The Permian red-beds studied in the present paper, framed
between two erosive surfaces, lay within the latter structural unit. They are unconformably
disposed over the underlying Devonian or Carboniferous rocks, and the top of their sequence is
eroded and overlain by the Lower–Middle Triassic Buntsandstein facies (Gómez-Gras 1987,
1992, 1993; Rosell et al. 1988, 1989a, 1989b; Bercovici et al. 2009; Linol et al. 2009). Those
beds were first attributed to the upper Permian by Bourrouilh (1973, 1983) and were subsequently
studied by Pomar-Gomà (1979), Obrador (1983), Martí et al. (1985), Rodríguez-Perea et al.
(1987), Arribas et al. (1990), Brandes & Tiedt (1991), Gómez-Gras (1987, 1992, 1993), Rosell et
al. (1988, 1989a, 1989b), Broutin et al. (1992), Gómez-Gras & Alonso-Zarza (2003), Bercovici
et al. (2009), Linol et al. (2009) and Borruel-Abadía et al. (2019).

          Despite of all these detailed works, the precise palaeogeographic position of Menorca
before the Alpine orogeny is still a matter of discussion. During the late Carboniferous–early
Permian, the extensional collapse of the Variscan orogen in Iberia and neighbouring regions
opened many rift basins, which were filled with continental sediments until the Middle Triassic
(López-Gómez et al. 2019a). Some authors (Gómez-Gras 1992, 1993; Sàbat et al. 2018) have
argued that the Menorcan sections have a sedimentary evolution that is somewhat reminiscent to
that of the basins of the SW of the Catalan Coastal Ranges, in the eastern margin of the Iberian
Peninsula. However, the palaeocurrent directions of the Permian and Triassic of Menorca point
generally towards the SW (Linol et al. 2009), whereas in the Iberian Peninsula the trend is towards
the SE (López-Gómez & Arche 1987, 1992; Arche & López-Gómez 1992), and therefore it is
unlikely that they were part of a same fluvial system or (sub)basin. The most probable scenario
with the data available today is that the Menorcan basin was relatively independent from the other
basins of Iberia, including that of the neighbouring island of Mallorca. In any case, the Menorcan
basin was probably located very close to the equator throughout the Permian, approximately in a
latitude of 4º N (Scotese 2014), at the western margin of the Palaeotethys ocean (Bercovici et al.
2009; Linol et al. 2009). The climate was tropical, alternating arid and hot seasons with rainy
seasons (Gómez-Gras & Alonso-Zarza 2003; Bercovici et al. 2009; Roscher et al. 2011).

        Gómez-Gras (1987) described three lithostratigraphic units for the Permian of Menorca
(informally named P1, P2 and P3), which were revised by Rosell et al. (1988, 1989a, 1989b),
Gómez-Gras (1992, 1993), Bercovici et al. (2009) and Linol et al. (2009). For the present paper,
one stratigraphic section has been logged in detail at the cliffs between Cala del Pilar and Pla de
Mar (Fig. 1B–C; Supplementary Material 1), encompassing the three lithostratigraphic units.



1.1. Palaeoenvironment and climatic conditions
The palaeoenvironments of the Permian recorded in Cala del Pilar–Pla de Mar section changed
through time, responding to the evolution of the basin and its climatic conditions. A review of the
three main lithostratigraphic units, based on the works of Gómez-Gras (1987, 1992, 1993), Rosell
et al. (1988, 1989a, 1989b), Gómez-Gras & Alonso-Zarza (2003), Bercovici et al. (2009), Linol
et al. (2009) and new data collected for the present study, is offered here:

        In the studied section, the P1 unit consists of 4–6 m of crudely bedded, coarse breccias
with intercalated sandstones, overlaying the angular, erosive boundary with the Carboniferous
Culm facies. In the first stages of rifting, when the subsidence rates are high, alluvial/colluvial
fans transverse to the main axis of the basin usually develop near the footwall scarp (e.g.,
Speksnijder 1985; Miall 2006; Franzel et al. 2020 and references therein). The P1 unit is here
interpreted as one of such deposits, and the formation of calcareous mature palaeosols on top of
each of the breccia beds (Gómez-Gras & Alonso-Zarza 2003; Bercovici et al. 2009) attests that
the depositional events that formed this unit were multiple, separated in time and under a climate
with periods of very low precipitation (Gómez-Gras & Alonso-Zarza 2003). Apart from
rhizocretions, no fossils have been reported from the P1 unit so far.
        In the studied section, the P2 unit consists of about 150 m of massive lutites with sporadic
intercalations of sandstones with climbing ripples and, rarely, microbreccias of reworked
pedogenic calcretes. This unit represents a playa lake palaeoenvironment (as defined by Briere
2000) in which lutites from overbank flows were deposited (Bercovici et al. 2009). Throughout
the sequence, there is an alternation of 1–12 m-thick lutitic packs with 0.25–1.5 m-thick intervals
that are more resistant to the erosion, with immature palaeosols and/or mud cracks. The former
correspond to the deposition of fine sediments during high water table periods, whereas the latter
reflect intervals of desiccation of the playa lakes and subsequent formation of mud cracks and
incipient palaeosols. Appearing between those, there are sandstone and microbreccia beds with
geometries ranging from lenticular (channelled flow) to tabular (unconfined flow), representing
crevasse splays and sheetfloods that reworked the floodplains in sporadic heavy rain events
(Gómez-Gras & Alonso-Zarza 2003). The fossil content of this unit consists of rhizocretions
developed in different types of palaeosols (Bercovici et al. 2009), and bones and bone fragments
that have been observed in a bed of reworked pedogenic calcrete fragments.

        The studied section also comprises the lower 170 m of the P3 unit, consisting of
sandstones intercalated with lutites. The bases of the sandstone elements are usually erosive, with
a lag of abundant reworked pedogenic calcretes from the floodplains (Gómez-Gras & Alonso-
Zarza 2003). Sandstones are organised in two main sequence types: the first, with lateral accreting
surfaces and a general upwards decrease of grain size, representing meandering channels, and the
second, consisting mostly of tabular beds with horizontal, low-angle cross stratification or
climbing ripple lamination, representing sheetflood deposits. Lutites are mostly massive and with
a pervasive development of calcareous palaeosols (Bercovici et al. 2009). This unit represents a
floodplain (playa, as per Briere 2000) with abundant vegetation under a seasonal climate. It was
traversed by meandering rivers and, during the rainy seasons, unconfined sheetfloods covered the
floodplain. One of the meandering channels, observed at m 301.5–303.5 of the studied section,
corresponds to sandstone and breccia beds with abundant lignite lenses and plant debris. This
channel was probably abandoned as an oxbow lake, where local reducing conditions favoured
precipitation of copper minerals (Crespí & Merino 1998; Llull & Perelló 2013). Other areas of
the floodplain were swamped or with a high water table for long time intervals, developing alfisols
(Bercovici et al. 2009), which have been recognised in several beds of this unit. The most
abundant fossils of the P3 unit are rhizocretions (Bercovici et al. 2009) and ichnofossils of the
Scoyenia ichnofacies, including tetrapod tracks. Bones and bone fragments are also locally
abundant as part of reworked pedogenic calcrete breccias.

        The uppermost part of the P3 unit, cropping out NW of Pla de Mar at Penyals d’Alforinet,
has not been considered in the present study because it is separated from the lower part by a very
thick covered interval, probably faulted and, moreover, no tetrapod fossils have been found there
so far. It was studied in great detail by Bercovici et al. (2009) and Linol et al. (2009), and the
palaeoenvironments there recorded are similar to those of the rest of the P3 unit.




2. Material and methods

2.1. Collection number abbreviations

FMNH: Field Museum of Natural History, Chicago, Illinois, United States of America.

IPS: Institut Català de Paleontologia Miquel Crusafont (formerly Institut de Paleontologia de
Sabadell), Sabadell, Barcelona, Spain.

MBCN: Museu Balear de Ciències Naturals, Sóller, Mallorca, Balearic Islands, Spain.

MNHN: Muséum National d’Histoire Naturelle, Paris, France.

MT: Macar de sa Teula, field code for the rock with the ichnites. It was left in the field (GPS
coordinates: 40° 3'9"N 3°58'24"E).



2.2. ZooBank registration of new names

New taxon names have been registered in ZooBank (http://zoobank.org) in order to comply with
the rules of the International Code of Zoological Nomenclature for electronic publications (article
8.5.3). The LSID for this publication is: urn:lsid:zoobank.org:pub:8153E0E1-9B66-4C55-89B9-
A246195DCD02.



2.3. Stratigraphy and sedimentology

For the stratigraphic and sedimentological study, one section has been logged in situ, bed by bed,
to a minimum resolution of 1 cm of bed thickness (in 1:25 scale), using a tape measure in well-
exposed outcrops and a Jacobs staff for lutite, semi-covered and covered intervals. This section,
named Cala del Pilar–Pla de Mar, is here presented in Supplementary Material 1 (in 1:40 scale),
and a synthetic version is in Figure 1C (in 1:1160 scale). The recognised sedimentary lithofacies
have been classified according to Miall (1985, 2006), Postma (1990), Mack et al. (1993), Gómez-
Gras & Alonso-Zarza (2003), Bercovici et al. (2009) and Linol et al. (2009) (Supplementary
Material 1).
2.4. Provenance and 3D modelling of tetrapod ichnofossils

The tetrapod ichnites studied in the present work (MT01) were all preserved as natural casts on
the surface of an ex situ rock found on the beach of Macar de sa Teula. The rock seemed freshly
detached from its original bed, which was determined on the outcrop that had to be the one from
m 174–179.5 (Fig. 1C), because both the bed and the ex situ rock had approximately the same
thickness and consisted in very fine sandstones (somewhat silty) with abundant invertebrate
burrows and common gleyed patches, unlike other nearby beds. Therefore, its position has been
indicated in Figure 1C with a question mark. A photogrammetric 3D model of the ichnites was
created (see ‘3. Systematic palaeoichnology’) and then the rock was left at the outcrop.

        Photogrammetry is a technique that has recently become widespread in ichnological
studies (e.g., Falkingham 2012; Citton et al. 2016; Mujal et al. 2016a, 2020), making it possible
to collect and save information that would otherwise be lost to erosion in the case of big,
unmovable rock surfaces. Moreover, it provides an alternative to the confection of artificial casts,
which are sometimes hard to make in open environments that are difficult to reach. The present
study has broadly followed the same methodology as Mujal et al. (2016a, 2020 and references
therein), using the open-source software MeshLab v2016.12 (http://meshlab.sourceforge.net/)
and ParaView 5.5.0-RC4 64-bit (http://www.paraview.org) to process the meshes. However, to
create the mesh, the licensed software Agisoft Photoscan standard v1.1.4. (www.agisoft.com) has
been used instead. In order to produce the 3D model, 89 pictures of the surface of MT01 were
taken from different angles and distances using a digital camera (Panasonic Lumix DMC-TZ27).
Then, they were aligned, and the dense point cloud and the mesh were created. After that, a false-
colour height map and contour lines were superimposed on the 3D model, and finally it was drawn
on a vector-based graphics design software and measured using the open-source software ImageJ
1.52d (https://imagej.nih.gov/ij/), following the criteria of Leonardi (1987) and Hasiotis et al.
(2007) (Table 1). The ichnites selected for study correspond to the category “1” of footprint
preservation scale by Marchetti et al. (2019b), that is, relatively poorly-preserved ichnites missing
some diagnostic structures (i.e., some digits). The other ichnites present on the slab scored a “0”,
that is, their preservation was very poor (Marchetti et al. 2019b), so they could not be studied.

        The 3D models herein studied are archived and freely available in MorphoSource
(https://www.morphosource.org/)       with   the    following    DOI:    MT01-1      and    MT01-2
(https://doi.org/10.17602/M2/M367858), MT01-10 (https://doi.org/10.17602/M2/M367864) and
MT01-13 (https://doi.org/10.17602/M2/M367870).
2.5. Phylogenetic analysis

The phylogenetic analysis was performed using a modified version (Supplementary Material 2)
of the matrix of Cisneros et al. (2020a), mainly with changes introduced by Modesto et al. (2019)
and Brocklehurst (2020). All character state changes for Captorhinikos chozaensis were applied
following Modesto et al. (2019), except for their character ‘72’ (here character ‘73’) as there was
no state 2 (see character list in Modesto et al. 2019). Character states for Moradisaurus were also
recoded following Modesto et al. (2019). The rest of character state changes listed by Modesto et
al. (2019) had already been applied in the matrix of Cisneros et al. (2020a). MBCN15730 (the
moradisaurine from Mallorca) and Kahneria were added to the matrix with the character state
codes of Brocklehurst (2020), modifying the following: character ‘10’ of the matrix used by
Brocklehurst (2020) was redefined into two characters by Cisneros et al. (2020a), so they are now
in both cases character ‘10’ with state 1 and character ‘11’ with state 1. Character ‘42’ of
MBCN15730 (character ‘41’ in Brocklehurst 2020) was changed from 1 to ?, as the ventral side
of the palatine is not visible on the specimen. Balearosaurus bombardensis gen. et sp. nov. and
the other indeterminate small moradisaurine from Menorca studied in the present work have been
coded first-hand. For the final analysis, both the indeterminate small moradisaurine from Menorca
and MAP PV664 (Moradisaurinae indet.) from Brazil (Cisneros et al. 2020a) were removed
because of their large amount of missing data, which caused significant polytomies in the
Moradisaurinae. Phylogenetic analysis was run using PAUP* v.4.0 (Swofford 2003) as a branch-
and-bound search with parsimony as the optimality criterion, unordered and unweighted
characters and with branches collapsing when their maximum length was zero. Then, a strict
consensus tree was computed, and bootstrap support values were calculated with 1000 repetitions,
not showing values under 50.



3. Systematic palaeoichnology

                             Ichnogenus Hyloidichnus Gilmore, 1927

                                        Hyloidichnus isp.

                                      (Fig. 2A–D; Table 1)

        Studied material. MT01-1, MT01-2, MT01-3, MT01-4, natural cast of a partial trackway
with a right manus pes set, a left pes imprint and a right pes imprint. MT01-5, natural cast of an
isolated left manus imprint. MT01-10, natural cast of a left ?pes imprint. Most of the other
footprints of the same surface (MT01-6, MT01-7, MT01-8, MT01-9, MT01-11, MT01-12) may
also belong to this ichnogenus given their similar size and general shape but their preservation is
too incomplete. All of them were found on an ex situ boulder at Macar de sa Teula, attributable
to the m 174–179.5 of Cala del Pilar–Pla de Mar section, P3 Unit, indeterminate Permian,
Menorca, Balearic Islands, western Mediterranean.

        Description. Pes imprints semiplantigrade, pentadactyl, probably slightly longer (26.4
mm) than wide. The most deeply imprinted parts are digits I and II (medial functional prevalence
of the autopodia). The digit imprints radiate from the sole and are relatively slender and straight,
with some tips ending in pointed claw traces. The relative length of the preserved digit imprints
can be ordered as follows (MT01-1): I<II<III<IV (digit V imprint is not preserved). The sole is
anteroposteriorly short, with a well marked posterior margin that is slightly concave. Manus
imprint slightly smaller than pes imprint, semiplantigrade, pentadactyl, wider than long. The most
deeply imprinted part is the distal region of digit IV, but digits I–III are not preserved so it is not
possible to evaluate the functional prevalence of the autopodia. The digit imprints radiate from
the palm and are straight and rather short, with tips ending in pointed claw traces. Given the faint
imprints of the two available manus (MT01-2 and MT01-5), the relative length of the preserved
digit imprints cannot be established, although digit IV appears to be the longest. Acute divergence
angle between digit IV–V imprints (21.4º). Palm anteroposteriorly short, with a well-marked
posterior margin that is very slightly concave. The imprints of the basal parts of all the digits are
well defined, and are the deepest imprinted areas of the sole. Quadrupedal trackway with a simple
alternating pattern, with a pace angulation of 71.86º for the pedes. The pes imprints are almost
parallel to the midline (divarication of 5º), whereas the manus imprints are strongly rotated
inwards (divarication of 44.6º) and seem to be slightly smaller than those of the pes. The pace of
the pes ranges between 64.6–69.4 mm, the length of the pace of the pes ranges between 35.4–43.3
mm, and the width of its pace is of 54.0 mm. The interpes distance is of 39.9 mm, and the manus-
pes distance is of 12.9 mm.

        Remarks. The following combination of characters allows to assign these footprints to
Hyloidichnus (see Gand 1988; Voigt 2005; Voigt et al. 2010; Marchetti 2016; Marchetti et al.
2020a; Logghe et al. 2021): (1) manus imprints slightly smaller than those of the pedes, (2)
orientation of pes imprints parallel to the midline, (3) manus imprints rotated inwards, (4) manus
imprint located internally to the pes imprint, (5) acute angle between manus digit IV–V imprints,
(6) digit imprints with clawed tips, (7) straight and radiating digits in both the pes and the manus
imprints, (8) short sole/palm imprints, (9) ectaxonic tracks and (10) medial-lateral decrease in
relief of the track imprints. However, the incomplete preservation of the manus imprints and the
trackway precludes any ichnospecies-level assignation. Captorhinomorph eureptiles, and more
specifically captorhinids and moradisaurine captorhinids, have been deemed as its most probable
trackmakers (e.g., Gand 1988; Haubold 2000; Gand & Durand 2006; Voigt et al. 2010; Logghe
et al. 2021), and this ichnogenus has been found from the Sakmarian (lower Permian) to the
Wuchiapingian (upper Permian) (e.g., Lucas 2019; Schneider et al. 2020; Logghe et al. 2021).
                               Ichnogenus Erpetopus Moodie, 1929

                                         cf. Erpetopus isp.

                                     (Fig. 2A–B, E; Table 1)

        Studied material. MT01-13, a natural cast of an isolated right ichnite, possibly a manus
imprint. Found on an ex situ boulder at Macar de sa Teula, attributable to the m 174–179.5 of
Cala del Pilar–Pla de Mar section, P3 Unit, indeterminate Permian, Menorca, Balearic Islands,
western Mediterranean.

        Description. Semiplantigrade, pentadactyl ichnite, slightly wider (11.5 mm) than long
(10.9 mm). The most deeply imprinted parts are the bases of the digit imprints, and, especially,
those of digits II and V. The digit imprints are thin and those of digits II–IV are distinctly curved
inwards distally, whereas the imprints of digits I and V are somewhat straight. Although some of
the digit tip imprints undoubtedly have drag traces (I and V), others show an slightly expanded
tip that may have corresponded to claw traces (II–IV). The relative length of the digit imprints
can be ordered as follows: V<I<II<III<IV. The divergence angles of digit IV–V imprints is high
(95.3º), and that of the digit I–V imprints forms a clearly obtuse angle (161.5º). The sole is
anteroposteriorly short, concave and well-imprinted posteriorly.

        Remarks. MT01-13 can be assigned to Erpetopus because of the following combination
of characters (Marchetti et al. 2014): (1) pes slightly wider than long, (2) slender, curved digit
imprints with clawed tips, (3) digit imprints with overlapping digit bases, typical of parareptiles
(Marchetti et al. 2020b), (4) short digit V imprint, (5) high IV–V divergence, (6) high I–V
divergence, (7) small size, less than 20 mm. The most probable trackmakers for Erpetopus are
acleistorhinid and nyctiphruretid parareptiles, and this ichnogenus has been found from the
middle Artinskian (lower Permian) to the Wuchiapingian (upper Permian), being the reference
ichnotaxon for the Erpetopus footprint biochron (e.g., Lucas 2019; Cisneros et al. 2020b;
Schneider et al. 2020).



4. Systematic vertebrate palaeontology

                                      Reptilia Laurenti, 1768

                                      Eureptilia Olson, 1947

                                Family Captorhinidae Case, 1911

                       Subfamily Moradisaurinae Ricqlès & Taquet, 1982
                                   Genus Balearosaurus gen. nov.

        Type and only included species. Balearosaurus bombardensis gen. et sp. nov.

        Origin of the name. Combination of Balearo-, as it was found in the Balearic Islands,
and -saurus, Latin for ‘lizard’.

        Diagnosis. As for the type species.



                          Balearosaurus bombardensis gen. et sp. nov.

                                             (Fig. 3A–F)

        Type specimen. holotype IPS35597 (fragment of right maxilla and palatine), Cala del
Pilar–Pla de Mar section, P3 Unit, indeterminate Permian, Menorca, Balearic Islands, western
Mediterranean.

        Origin of the name. Because most of the fossils here considered to belong to this species
were found in the coastal zone called Sa Bombarda (Menorca, Balearic Islands, western
Mediterranean).

        Studied material. IPS35597 (fragment of right maxilla and palatine), from an ex situ
rock at Punta des Carregador, attributable to m 149.5 of Cala del Pilar–Pla de Mar section. From
the P3 Unit, indeterminate Permian, Menorca, Balearic Islands, western Mediterranean.

        Diagnosis. Large moradisaurine captorhinid eureptile with a maxilla with at least three
rows of cylindrical teeth that possess an external ornamentation based on longitudinal thin ridges
and furrows.

        Description. Fragment of right maxilla and palatine of 67.0 mm of maximum
anteroposterior length, 25.6 mm of maximum labiolingual width and 27.1 mm of maximum
dorsoventral height. No sutures are visible. Three rows of alveoli can be observed: the one in the
lingual side shows traces of six alveoli, all of them sectioned. Some still have remains of
thecodont teeth attached. The middle row has also six partially covered alveoli. The labial row
has five preserved alveoli, three of which are also sectioned and two that are covered by matrix.
All of them have a similar size (maximum diameter of 6.4–7.4 mm), and are arranged diagonally
to each other. Horizontally on the occlusal side of the maxilla there is a partial isolated cylindrical
tooth. Its diameter (7.8 mm) agrees with that of the surrounding alveoli, and its outer surface is
covered by an ornamentation consisting of numerous and very thin longitudinal furrows and
ridges (Fig. 3D3). On the dorsal side of the maxilla there is a flat surface corresponding to the
palatine, tilted 27.3º towards the medial part of the cranium.
        Remarks. The maxilla clearly agrees with those of large moradisaurine captorhinid
eureptiles. IPS35597 shows at least three parallel rows of teeth; the presence of several
longitudinal rows of teeth, organised approximately parallel to the jaw margins, is a diagnostic
character of Moradisaurinae (Vjushkov & Chudinov 1957; Olson 1962a, 1962b, 1965; Ricqlès &
Taquet 1982; Ricqlès & Bolt 1983; Jalil & Dutuit 1996; Ivakhnenko 2008; Reisz et al. 2011;
Modesto et al. 2014, 2016, 2019; LeBlanc & Reisz 2015; LeBlanc et al. 2015; Jung & Sumida
2017). The maxillary teeth are of a similar diameter than that of the largest members of the
subfamily, such as Labidosaurikos (see Dodick & Modesto 1995), Moradisaurus (see Ricqlès &
Taquet 1982; Modesto et al. 2019), Rothianiscus (see Olson 1962a, 1965), the unidentified tooth
plates from the ‘KB’ locality of Texas (Modesto et al. 2016) and Mallorca (Liebrecht et al. 2017).
However, the teeth of all the species in those genera have a smooth surface, devoid of any kind
of ornamentation (Olson 1962a, 1965; Ricqlès & Taquet 1982; Dodick & Modesto 1995; Modesto
et al. 2016, 2019; Liebrecht et al. 2017), contrarily to what can be observed on the isolated tooth
on the surface of the maxilla in IPS35597, which is traversed by numerous longitudinal furrows
and ridges. Only the Captorhinikos sp. described by Cisneros et al. (2020a: fig. 2) has small
furrows and ridges on some teeth, but they seem to be restricted on the base of the crown,
contrarily to the isolated tooth of IPS35597, which has a much denser ornamentation that
completely covers the preserved surface of the tooth.

        The phylogenetic analysis (Fig. 4) places B. bombardensis as a derived species within the
moradisaurine captorhinids, sister to the undetermined moradisaurine of the neighbouring island
of Mallorca, based mostly on the low number of tooth rows. Those two, in turn, are a sister clade
of the North American Rothianiscus, a genus of large forms with also relatively few rows of teeth,
similarly to the Balearic species.



                        cf. Balearosaurus bombardensis gen. et sp. nov.

                                            (Figs. 5–6)

        Studied material. IPS35588 (chevron?), IPS35590 (middle caudal vertebra), IPS35592
(anterior dorsal vertebra), IPS35598 (distal fragment of left jaw), IPS120163 (right ilium),
IPS120164 (left pubis) and IPS120165 (proximal epiphysis of left tibia), all found in close
association in an ex situ rock at Sa Bombarda, attributable to m 226–227 of Cala del Pilar–Pla de
Mar section. All of them come from the P3 Unit, indeterminate Permian, Menorca, Balearic
Islands, western Mediterranean.

        Description. IPS35598 (Fig. 5A–F): Distal fragment of left jaw of 66.5 mm of maximum
anteroposterior length, 30.9 mm of maximum labiolingual width and 35.4 mm of maximum
dorsoventral height. No sutures are visible. The anterior and posterior ends are broken off, and
the occlusal region and part of the lingual and ventral sides are strongly abraded. Although the
teeth are missing, one row of five alveoli, which are hemiellipsoidal in shape, can be observed.
The first two alveoli are tilted anteriorly, whereas the other three point dorsally. All the alveoli
are relatively small (5.7–6.1 mm of maximum diameter) except for the fourth, which is clearly
the largest (15.2 mm of diameter), and must certainly have born a large caniniform. Given the
symmetrical shape of the alveoli, the mode of attachment of the teeth was thecodont. In dorsal
aspect, the jaw is narrowest at its anterior end, and its lingual side expands considerably near the
largest alveolus. In labial aspect, the surface is rather flat, and it is traversed by several shallow
grooves. In ventral aspect, it possesses a longitudinal groove.

        IPS35592 (Fig. 5G–L): Anterior dorsal vertebra of 92.0 mm of height, 93.8 mm of
maximum width and 53.0 mm of maximum length. Anteroposteriorly compressed, amphicoelous
pleurocentrum of 36.2 mm of height, 42.0 mm of width and 26.8 mm of length, its axis slanting
24º anteriorly with respect to the horizontal. The outline of the pleurocentrum is circular in
anteroposterior view and spool-shaped in lateral view, because the cortical rim is slightly flared
outwards laterally and ventrally. In ventral aspect, the pleurocentrum is slightly flattened, and no
evidence of a ridge or keel can be observed. The neural canal has a somewhat pentagonal contour,
being more rounded in anterior view (10.5 mm high × 14.7 mm wide) than in posterior view (8.4
mm high × 13.9 mm wide), flattening the dorsal edge of the pleurocentrum. The pedicels are
attached dorsolaterally to the pleurocentrum, anteriorly developing a rather shallow, small fossa
just above the cortical rim. From the anterior lateroventral sides of the neural canal, two rounded
centroprezygapophyseal processes extend laterally on the pedicels, and possess associated
infraprezygapophyseal fossae dorsally, just below the edge of the articular surfaces of the
prezygapophyses. The neural arch that stands above is notably expanded and swollen, extending
out as much as the width of the pleurocentrum. The prezygapophyses extend laterally from the
pedicels (each apophysis corresponding to 1/3 of the total width of the vertebra) and are connected
to the transverse processes (diapophysis + parapophysis) posterolaterally. The articular surfaces
of the prezygapophyses are slightly tilted inwards from the horizontal plane (10º), and possess a
faintly convex obovate contour, which is twice as wide laterally than it is anteroposteriorly. From
the medial edges of the prezygapophyses, two carinae extend dorsally, converging at the base of
the neural spine. The transverse processes are located between the pre- and postzygapophyses,
and are tilted 27º from the vertical axis in anteroposterior aspect. The diapophysis is slightly
(15%) thicker than the parapophysis, and they are both connected by an osseous lamina with an
angle of 13º from the vertical axis in lateral view. Whereas the diapophysis is dorsolaterally
detached forming a small process, the parapophysis fuses at midlength of the posterior region of
the prezygapophysis, being reduced to a small bulge. The postzygapophyses are located just
behind the diapophyses in anterior view, separated by a rather deep emargination. A small,
laterally elongated suprapostzygapophyseal fossa is present anteriorly on the emarginated side.
The postzygapophyseal articular facets are slightly tilted inwards (6.5º) from the horizontal plane,
and possess a flat surface. The margins of these surfaces are slightly flared outwards, extending
as ridges towards the roof of the neural channel, delimiting the postspinal fossa, which possesses
a distinct triangular shape. The hypothetical two edges of the base of that triangle appear on the
laminae framing it as two small, dorsolaterally elongated centropostzygapophyseal processes. The
dorsal outline of the neural arch in anteroposterior aspect is rather flat, only with small undulations
corresponding to the two postzygapophyses and the base of the neural spine. The neural spine is
very low (10% of the total height in anterior view) and thin (6% of the total width).

        IPS35590 (Fig. 5M–R): Middle caudal vertebra of 44.3 mm of preserved height, 24.8 mm
of maximum width and 39.8 mm of maximum length. Cylindrical, amphicoelous pleurocentrum
of 28.3 mm of height, 24.8 mm of width and 26.7 mm of length, its axis slanting 13.5º anteriorly
with respect to the horizontal. The cortical rim is slightly flared outwards, and it bears a
conspicuous bulge on the ventral part of the anterior side, located dorsally just between the haemal
keels. In ventral aspect, two haemal keels traverse the pleurocentrum, being more prominent on
the anterior cortical rim, and decreasing in height towards the posterior end. No clear facets for
the haemal arch have been observed. The neural canal has a rectangular contour in anterior view
(12.8 mm high × 9.7 mm wide) and is narrower and almost circular in posterior view (8.8 mm
high × 10.3 mm wide). In anterior aspect, the neural arch is broken just above the neural canal.
Conversely, in posterior aspect, the postzygapophyses can be observed, the right one being
complete. It is strongly directed posteriorly and the articular surface is flat and slightly tilted
inwards (24.5º). The neural spine is not preserved.

        IPS35588 (Fig. 5S–T): Possible fragment of haemal arch (chevron) of 37.5 mm of
maximum dorsoventral height, 7.9 mm of lateral width and 14.7 mm of anteroposterior length.
Laterally compressed, dorsoventrally elongated fragment, with a rounded anterior margin that
becomes thinner posteriorly. Its distal region is broken; its proximal region, corresponding to the
articular surface, is not completely ossified and somewhat irregular, forming an angle of about
65.3º respect to the main axis of the bone.

        IPS120163 (Fig. 6A–F): Right ilium, with a lateral surface that appears to be smooth and
with no trace of the acetabulum. Anteriorly, the bone ends abruptly in a flat, unfinished surface,
corresponding to the suture with the pubis. Ventrally and posteriorly, the bone is eroded, as it was
the exposed part when it was found, thus missing the sutural surfaces to the ischium and part of
that to the pubis. On its medial surface, there is a somewhat oval area of attachment of the sacral
ribs, of 66.6–77.1 mm of diameter. It is located anteriorly to the iliac neck; its dorsal margin is
slightly protruding, its anterior margin is somewhat depressed, and its posterior margin is flat and
continuous with the rest of the bone. The iliac blade (123.1 mm of length, 72.6 mm of maximum
width and 47.6 mm of height) forms an angle of about 63.4º with the posterior part of the bone.
Its neck has a semicircular section, dorsally flattened and with a rounded ventral part, and the
blade is elongated, dorsoventrally compressed and expanded distally, with a flattened triangular
section. Its posterior end has an unfinished, irregular surface.

        IPS120164 (Fig. 6G–I): Left pubis consisting of a thin, relatively flat, triangular plate
(148.1 mm of maximum anteroposterior length and 142.8 mm of maximum height), which is
slightly curved ventromedially. The maximum lateral width is around its posterior-dorsal edge,
reaching 32.3 mm. The anterior, dorsal and posterior margins of the plate are either unfinished or
broken, whereas the ventral margin becomes progressively thinner and sharp-edged. The
obturator foramen has a subtriangular to oval contour (13.5–20.1 mm of height × 12.3–13-3 mm
of width), and obliquely pierces the bone from an anterior-dorsal position in the medial side to a
posterior-ventral position on the lateral side.

        IPS120165 (Fig. 6J–O): Fragment of the proximal epiphysis of a left tibia, of 131.8 mm
of maximum proximal-distal length, with an articular surface of 108.5 mm of anteroposterior
width and 96.4 mm of mediolateral width. Most of the medial part of the shaft has been eroded,
as it was exposed on the surface when the fossil was found. Articular surfaces can be distinguished
on the tibial plateau with some degree of confidence, even though there the bone is slightly eroded
(or was not completely ossified). In the lateral half of the plateau, there is a somewhat semicircular
depression to accommodate the lateral condyle of the femur. Additionally, another (less clear)
elongated or lunate depression can be observed on the medial-extensor edges of the plateau,
corresponding to the articulation surface for the medial condyle of the femur. In extensor view,
the most proximal part of the cnemial crest can be observed, and although it has been mostly
eroded, it appears to bear a fairly inconspicuous knob. Moreover, in lateral view, there is a
conspicuous ridge about 44.5 mm below the edge of the tibial plateau.

        Remarks. All the bone remains here considered were found in close association, albeit
not articulated, so given their consistent size and lack of duplicate elements they can all be
considered to belong to the same individual. IPS35597, the holotype specimen of Balearosaurus
bombardensis gen. et. sp. nov., was collected from a lower stratigraphic position, and given its
consistent size and taxonomical attribution it could be considered to be conspecific with the
remains herein identified as cf. Balearosaurus bombardensis gen. et. sp. nov. However, there is
no decisive proof that this specimen (mostly represented by postcranial elements) belongs to the
same species as the holotype maxilla of Balearosaurus bombardensis gen. et. sp. nov., and
therefore it is here treated separately under open nomenclature.
         Cranial remains clearly agree with those of large moradisaurine captorhinid eureptiles.
IPS35598 is conspicuously heterodont, differentiating a caniniform from other smaller teeth, a
condition that is not known to occur in the other Permian tetrapods with swollen vertebral neural
arches such as seymouriamorphs and diadectomorphs (see below), which have teeth of similar
size in the anterior region of the jaws (e.g., Case 1911; Case & Williston 1912; White 1939; Olson
1947; Carroll et al. 1972; Berman et al. 1987, 1998; Berman & Sumida 1995; Kissel 2010).
Conversely, the dentition of moradisaurines does difference relatively small, bullet-shaped teeth
and larger caniniforms (Vjushkov & Chudinov 1957; Olson 1962a, 1965; Ricqlès & Taquet 1982;
Dodick & Modesto 1995; Ivakhnenko 2008; LeBlanc et al. 2015; Modesto et al. 2019). However,
the fact that IPS35598 is broken and abraded precludes detailed comparison with other species;
regardless, it can be stated that the alveolus for the caniniform is approximately as large as that
of the largest known captorhinid, Moradisaurus grandis Taquet, 1969 (see Ricqlès & Taquet
1982).

         Elements of the axial skeleton, especially IPS35592, are also diagnostic of
moradisaurines. Swollen vertebral neural arches are found in seymouriamorphs, diadectomorphs,
moradisaurine captorhinomorphs and parareptiles (e.g., Olson & Beerbower 1953; Olson 1962a,
1962b, 1979; Olson & Barghusen 1962; Kuhn 1969; Sullivan & Reisz 1999; Modesto et al. 2014).
Contrarily to the Menorcan material, seymouriamorph anterior dorsal vertebrae show distinct
diapophyses that laterally extend past the zygapophyses (White 1939; Sumida 1990). Moreover,
in seymouriamorphs, the parapophyses are located on the intercentra (White 1939; Sumida 1990),
whereas in IPS35592 they are on the lateral sides of the neural arches, connected to the
diapophyses by a thin lamina, a condition that is seen in captorhinomorphs (e.g., Olson 1962a,
1962b; Olson & Barghusen 1962; Sumida 1990; Reisz et al. 2011). Dorsal vertebrae of
diadectomorphs and parareptiles are also reminiscent of IPS35592, however, they always possess
a thickened and dorsally elongated neural spine, and additional articulation facets in the form of
the hypantrum-hyposphene complex (Meyer 1860; Stappenbeck 1905; Case 1911; Kuhn 1969;
Carroll et al. 1972; Sumida 1990; Berman et al. 1998; Nyakatura et al. 2015). The vertebra studied
herein does possess what seem to be paired, small additional articulation facets, but in the form
of the centrozygapophyseal processes and fossae, which are by no means comparable to the stout
and conspicuous hypantrum-hyposphene of diadectomorphs and parareptiles. Illustration of
isolated vertebral remains of moradisaurines is scarce in the literature, but IPS35592 is
remarkably similar to the Rothianiscus vertebra (FMNH UR 829) illustrated by Olson &
Barghusen (1962) (R.M.A., pers. obs.) and to a purported juvenile Moradisaurus vertebra,
uncatalogued, in the collections of the MNHN (J.F. & R.M.A., pers. obs.).

         The elements of the pelvic girdle are slightly different from those of other moradisaurines
of which the pelvis is known, such as Captorhinikos (see Olson 1962b) and Rothianiscus (see
Olson & Barghusen 1962), in that the iliac blade is dorsoventrally flatter and more posteriorly
directed in IPS120163. Some smaller captorhinids, such as Captorhinus Cope, 1896, do have iliac
blades strongly directed posteriorly (see Holmes 2003), but, apart from in its size, they differ from
IPS120163 in that the blade is dorsoventrally flattened in the latter.



                                      Moradisaurinae indet.

                                               (Fig. 7)

        Studied material. IPS35593 (middle/posterior dorsal vertebra), found in an ex situ rock
attributable to m 226–227 of Cala del Pilar–Pla de Mar section (the same as the specimens
IPS35588, IPS35590, IPS35592, IPS35598, IPS120163, IPS120164 and IPS120165 mentioned
above). IPS120166 (proximal fragment of left jaw), collected in situ from the bed at m 273–274
of Cala del Pilar–Pla de Mar section. Both of them come from the P3 Unit, indeterminate Permian,
Menorca, Balearic Islands, western Mediterranean.

        Description. IPS120166 (Fig. 7A–F): Proximal fragment of left jaw of 42.6 mm of
maximum anteroposterior length, 13.6 mm of maximum labiolingual width and 26.6 mm of
maximum dorsoventral height. Five bones are partially represented in the studied fragment,
although only sutures between two pairs of them are visible (prearticular-splenial and angular-
prearticular). Three rows of teeth can be observed on a platform on the dentary, overhanging in
the lingual side (11.9 mm of maximum labiolingual width and 7.6 mm of maximum dorsoventral
height). Four small (2.0 mm of maximum diameter), bullet-shaped teeth are preserved in the labial
row. Detailed preparation has not been possible due to its small size and the potential risk of
damaging the fossil, but they seem to be conical and somewhat pointed. Four teeth can be
distinguished in the middle row, the most posterior of which is clearly larger (5.0 mm of
maximum diameter). Two other small teeth have been counted in the lingual row. All of them are
arranged diagonally to each other. In labial view, the dentary is rather flat and tilted laterally
(38.3º), and its lower two-thirds are ornamented with irregular grooves. Posterior to the teeth plate
rises the coronoid process (tilted 48.3º posteriorly), although the suture between the dentary and
the coronoid is not visible, and part of the mandibular ramus. In lingual view, just below the tooth
plate there is a flat and smooth surface corresponding to the prearticular. In its posterior part, and
although it is covered by matrix, there is an area that corresponds to the articular facet of the
hemimandible. The ventral edge of the prearticular is connected to the angular below with a
distinct suture and a conspicuous angulation of the surface, which becomes almost horizontal. In
the most anterior preserved part of the connexion between the prearticular and the angular there
is a anteroposteriorly stretched foramen (Meckelian foramen) that connects to the mandibular
canal visible in anterior aspect. Just below this foramen there is a small portion of the splenial,
connecting posteriorly and ventrally with the angular by means of a conspicuous suture.

        IPS35588 (Fig. 7G–L): Middle/posterior dorsal vertebra of 33.9 mm of height, 38.0 mm
of maximum width and 26.9 mm of maximum length. Cylindrical, amphicoelous pleurocentrum
of 14.5 mm of height, 14.6 mm of width and 17.2 mm of length, its axis being almost horizontal.
The outline of the pleurocentrum is circular in anteroposterior view and spool-shaped in lateral
view, because the cortical rim is slightly flared outwards laterally and ventrally. In ventral aspect,
there is no evidence of a ridge or keel. The neural canal has a somewhat pentagonal contour in
anterior view (7.1 mm of height × 7.9 mm of width) and is covered by matrix in posterior view.
The pedicels are attached dorsolaterally to the pleurocentrum supporting the neural arch, which
is notably expanded and swollen, extending out as much as the width of the pleurocentrum. The
prezygapophyses extend laterally from the pedicels and are connected to the transverse processes
posterolaterally. The articular surfaces of the prezygapophyses are essentially horizontal, and are
approximately twice as wide laterally than they are wide anteroposteriorly. Transverse processes
are located between the pre- and postzygapophyses, and are tilted 23.1º from the vertical axis in
anteroposterior aspect. The diapophysis appears to be half as thick as the parapophysis, and they
are both connected by an osseous lamina with an angle of 31º from the vertical axis in lateral
view. Whereas the diapophysis is dorsolaterally detached forming a small process, the
parapophysis fuses at midlength of the posterior region of the prezygapophysis. The
postzygapophyses are located just behind the diapophyses in anterior view, separated by a rather
deep emargination. A small, laterally-elongated suprapostzygapophyseal fossa is present
anteriorly on the emarginated side. The postzygapophyseal articular facets essentially horizontal,
possess a flat surface, and their margins are slightly flared outwards. The neural spine is very low
(8% of the total height in anterior view) and thin (7% of the total width). In anterior aspect, it
continues ventrally as a faint lamina that fades halfway to the neural canal; in posterior aspect,
the spine bifurcates ventrally in two thin laminae that delimit the postspinal fossa, which possesses
a distinct triangular shape.

        Remarks. The fossils here considered come from two beds separated by a thickness of
about 50 m. Therefore, they certainly do not belong to the same specimen (the vertebra would
belong to a slightly larger animal), but they have been grouped here because they agree in general
size and purported taxonomical attribution. The vertebra (IPS35588) shows typical moradisaurine
traits and it is essentially a smaller version of IPS35592, very similar to the vertebrae illustrated
by Reisz et al. (2011). However, it does not belong to a juvenile specimen of cf. Balearosaurus
bombardensis but to an adult of a distinct, smaller species, as it is completely ossified and there
remain no traces of the neurocentral suture. The jaw (IPS120166) is also small, and broadly
comparable to that of some genera of small moradisaurines such as Captorhinikos (see Olson
1962b; LeBlanc et al. 2015; Cisneros et al. 2020a), Kahneria (see Olson 1962a), Gecatogomphius
(see Ivakhnenko 2008), Acrodenta (see Jalil & Dutuit 1996) and the unidentified tooth plate from
the Argana Basin (Jalil & Dutuit 1996). It differs from most of those genera in that IPS120166
only has three rows of teeth in the most proximal part of the jaw, whereas the others have four or
more with a comparable or smaller jaw size. Acrodenta does have three rows of teeth, and differs
from all other moradisaurine captorhinids in the acrodont mode of implantation of its teeth, which
are thin and sharply pointed (Jalil & Dutuit 1996). Teeth in IPS120166 are not as thin and pointed
as in Acrodenta, as they are more similar to the bullet-shaped teeth of Captorhinikos or Kahneria,
and their mode of implantation cannot be observed in the present material. Therefore, it has been
identified in open nomenclature.



5. Discussion
5.1. Age attribution

The precise age attribution for each of the Permian units of Menorca remains mostly unresolved.
Bourrouilh (1973, 1983) was the first author to carry out a palynological study on those units with
a sample collected in the km 16.9 of the road from Es Mercadal to Alaior, which pointed to an
upper Permian age (Bourrouilh 1973, 1983). That outcrop was assigned to the lower half of the
P3 unit by Rosell et al. (1989a, 1989b), who also provided another palynological analysis from
an unspecified locality that revealed a ‘Thuringian’ biofacies (middle–upper Permian). A few
years later, Broutin et al. (1992) reported yet another palynoassemblage from Pla de Mar, found
in the copper mine beds (in m 301.5–303.5 of the log presented here, and thus in the middle part
of the P3 unit), and also considered it to belong to the ‘Thuringian’ biofacies. That palyniferous
horizon could not be relocated by Bercovici et al. (2009), but they did find more layers that
yielded palynomorphs in the uppermost beds of the P3 unit at Penyals d’Alforinet (not considered
herein, see ‘1.1. Palaeoenvironment and climatic conditions’ above), arguing a Wordian–
Changhsingian stage (middle–uppermost Permian) interval for them. More recent works, such as
Bourquin et al. (2011) or Borruel-Abadía et al. (2019), considered that palynoassemblage to be
of lower Wuchiapingian stage (Lopingian, upper Permian) without providing further proof. Then,
they inferred that the lower–middle P3 unit was of upper Capitanian stage (Guadalupian, middle
Permian), the P2 unit was of Wordian–lower Capitanian stage (Guadalupian, middle Permian)
and the P1 unit was of lower Wordian stage (Guadalupian, middle Permian), without presenting
specific data or any compelling argument on how this conclusions were reached.

        From a review of the literature, it becomes clear that the only interval of the Permian of
Menorca that has been confidently dated, albeit in a notably wide range of time, is the middle–
upper part of the P3 unit as Wordian–Changhsingian (middle–uppermost Permian) (Bourrouilh
1973, 1983; Rosell et al. 1989a, 1989b; Broutin et al. 1992; Bercovici et al. 2009). Additionally,
the ichnological study of the present work has dated the lower part of the P3 unit as middle
Artinskian–Wuchiapingian. All other age inferences, especially those for the lower units, are here
considered unfounded, as with the present data it is only possible to attribute the P3 unit to an
undetermined interval between the middle Artinskian and the Changhsingian (lower–uppermost
Permian), lacking any data for units P1 and P2.



5.2. Tetrapod fauna

All the body fossils from the Permian P3 Unit of Cala del Pilar–Pla de Mar section have been
identified to belong to the captorhinid eureptile subfamily Moradisaurinae, similarly to most of
the ichnological material, which was produced by captorinomorphs, perhaps moradisaurines as
well (Hyloidichnus isp.) (Fig. 8). The lack of precise age constraints in the case of the Menorcan
units limits the possibility of making detailed palaeobiogeographical inferences. Still, this section
will explore the possible relationships with all the other similar species.

        5.2.1. Palaeobiogeography of moradisaurine captorhinid eureptiles. The distribution of
all known moradisaurine fossils (bones and putative ichnites) throughout the Permian was
essentially restricted to low palaeolatitudes between 30ºN and 30ºS (Fig. 9) (the only exception
being the Hyloidichnus reported from Argentina by Melchor & Sarjeant 2004). Modesto et al.
(2016) suggested that moradisaurines and caseids replaced diadectids and edaphosaurids as the
dominant high-fibre herbivores in the late part of the early Permian because they may have been
better suited to thrive in more arid climates. Indeed, from the early Permian to the middle–late
Permian, the low-latitude belt of Pangaea shifted from a tropical climate to an arid climate (Tabor
& Poulsen 2008). With moradisaurines restricted to intertropical latitudes, the niches as dominant
herbivores in temperate and high latitudes were filled, during the middle and late Permian, by
taxa of other groups such as dicynodonts, pareiasaurs and some dinocephalians (e.g., Day et al.
2015; Bernardi et al. 2017; Olroyd & Sidor 2017; Sennikov & Golubev 2017; Marchetti et al.
2019c; Viglietti et al. 2019). Such latitudinal provincialism was supported by the analysis of
Bernardi et al. (2017), who showed that the late Permian faunal palaeoassemblages of low
latitudes clustered in what were named “tropical faunas”, which were clearly distinct from the
palaeoassemblages of higher latitudes. This had also been argued by Sidor et al. (2005) regarding
the singular middle/upper? Permian assemblage of the Moradi Formation of Niger, with relict
representatives of Carboniferous temnospondyl clades that were little related to other coeval taxa.
The present work adds up to that evidence, as the distribution of moradisaurines, from the early
Permian to the late Permian (Fig. 9), supports the hypothesis of a strong latitudinal provincialism,
especially isolating the faunas of the most arid, intertropical regions of Pangaea.
        Therefore, if central Pangaea was an area that hindered faunal exchanges between
temperate latitudes of both hemispheres, the alternative corridors that explain the great similarities
between northern and southern temperate faunas should be sought either in the coastal
environments, with less harsh climates (Sidor et al. 2005), or in the Cathaysian Bridge, which
preserved more humid conditions throughout the Permian (Tabor & Poulsen 2008). Brocklehurst
et al. (2018) argued that, in all cases, the Permian assemblages of Gondwana were more similar
to the ones of eastern Laurasia, whereas it seemed that dispersion had been low between
Gondwana and western Laurasia (which includes most of the moradisaurine localities). Thus, the
most probable explanation was that the Cathaysian Bridge operated as the main dispersal route at
least until the Guadalupian (middle Permian), and that the most important dispersal barrier
between western Gondwana and western Laurasia were the high mountains of the Variscan
orogen (Brocklehurst et al. 2018). Among the different clades included in the analysis, eureptiles
seemed to be the group least affected by this barrier, as their dispersal and vicariance rates
remained relatively stable throughout the period of uplifting of the mountains (Brocklehurst et al.
2018). This agrees with the pattern observed in Figure 9 herein, which shows that moradisaurines
were present and radiated in both the northern and southern sides of the Variscan mountains from
the very beginning of their evolutionary history. Therefore, even though it appears that the arid
climatic belt in central Pangaea or the Variscan mountains could have served as a strong obstacle
for dispersion of certain tetrapod groups such as amphibians, parareptiles and synapsids
(Brocklehurst et al. 2018), they provided comfortable environments for a specialised clade such
as moradisaurines.

        5.2.2. Phylogenetic relationships of moradisaurine captorhinid eureptiles. The
phylogenetic tree of the Captorhinomorpha obtained in the present work (Fig. 4) differs in some
aspects from those recently published; specifically, it recovers one polytomy in all the species of
Captorhinus, the genus Labidosauriscus and the clade (Labidosaurus + Moradisaurinae), and
another polytomy including Captorhinikos valensis, Kahneria and all the other moradisaurines
except for Captorhinikos chozaensis. The first politomy is probably the result of merging the
character matrix of Modesto et al. (2019), resulting in a polytomy between Captorhinus aguti,
Captorhinus laticeps and Captorhinus magnus, and the character matrix provided by Cisneros et
al. (2020a), which obtains a polytomy between Captorhinus kierani, Labidosauriscus and
(Labidosaurus + Moradisaurinae). In the former, the polytomy is caused by coding changes in
Captorhinikos chozaensis, which have been verified again in the present work; in the latter, it is
caused by the addition of the two recently described taxa Captorhinus kierani and
Labidosauriscus richardi. The second polytomy is obtained as a result of adding Kahneria to the
matrix; nevertheless, it does not affect the clade (Balearic species + Rothianiscus), which is
recovered regardless of Kahneria being included in the data matrix or not.
        A significative topological difference between the trees of Modesto et al. (2019) and
Cisneros et al. (2020a) is in the position of the single tooth-rowed genus Labidosaurus. It is
recovered outside all the multiple tooth-rowed Moradisaurinae in the former, whereas in the latter
it appears between Captorhinikos chozaensis and the rest of multiple tooth-rowed moradisaurines.
The tree presented in Figure 4 concurs with the tree recovered by Modesto et al. (2019). This
aspect has important implications for the phylogeny of the Moradisaurinae, making it a clade
restricted to the species with several rows of teeth parallel to the jaw margin, implying that high-
fibre herbivory evolved only once within the Captorhinomorpha. In any case, the topology within
derived moradisaurines remains the same in the three trees, with the lower–middle Permian North
American genus Rothianiscus, with one species with three rows of teeth in the major part of its
tooth plates (Olson 1962a) as sister to the two large species from Mallorca (Liebrecht et al. 2017)
and Menorca (Fig. 4).

        The large moradisaurine from the island of Mallorca was described by Liebrecht et al.
(2017), based on a fragment of right maxilla and parts of the palate that belonged to an unknown,
large species with three rows of teeth. It was initially assumed (Liebrecht et al. 2017) to be of
upper Permian age based on the work of Ramos & Doubinger (1989), which dated the
palynoassemblages of the upper lithostratigraphic unit of the Permian of the island (Pedra de
s’Ase Unit) as ‘Thuringian’, and thus as middle–upper Permian. However, the moradisaurine
fossil was collected in the lower unit (Port des Canonge Unit) (Liebrecht et al. 2017), which did
not have any reliable age attribution. That unit is now currently under study, and has been
preliminarily dated as lower Permian (Artinskian–Kungurian) based on its tetrapod ichnological
assemblage (Matamales-Andreu et al. 2019). Therefore, the unidentified moradisaurine from
Mallorca (Liebrecht et al. 2017) should be considered of lower Permian age awaiting further
available paleontological and geological data.

        As stated above, the phylogenetic analysis offered in the present work (Fig. 4) places this
taxon as sister to the large captorhinid from the neighbouring island of Menorca described herein,
Balearosaurus bombardensis gen. et sp. nov. They belong, however, to clearly distinct species,
and possibly genera, which can be set apart mostly based on dental characters, as the Mallorcan
moradisaurine has smooth, bulbous teeth (Liebrecht et al. 2017), whereas in the Menorcan species
the teeth are more cylindrical and ornamented with numerous ridges and furrows (Fig. 3). Despite
of its great palaeogeographical proximity, it is important to stress that the Permian units of eastern
Iberia (including what are now the Balearic Islands) were deposited in small, semi-isolated half-
graben basins (e.g., Gómez-Gras 1992, 1993), which probably operated as biogeographical
islands for local speciation of some groups such as moradisaurines.
        The close relationship of Rothianiscus with the two large moradisaurines of the Balearic
Islands further supports the hypothesis put forward in ‘5.2.1. Palaeobiogeography of
moradisaurine captorhinid eureptiles’, since the former genus has been found in southern North
America, which was on the northwestern side of the Variscan mountains, whereas the Balearic
Islands were on its southeastern side (Fig. 9). Therefore, the general case made for all
Moradisaurinae is here repeated in a smaller scale, with closely related taxa separated by the
Variscan mountains, suggesting that they were not a strong barrier to dispersal of eureptiles.

        Regarding the small moradisaurine of Menorca described in the present work, which was
impossible to determine with the present material, its relationships within the Moradisaurinae are
less clear, and will not be discussed here awaiting the discovery of more complete specimens in
the future.



6. Conclusions

The present work has characterised, by means of ichnological and osteological data, a
palaeoassemblage from an indeterminate Permian of Cala del Pilar–Pla de Mar section (Menorca,
Balearic Islands, western Mediterranean) dominated by moradisaurine captorhinid eureptiles. The
field study has allowed to locate and characterise the palaeoenvironments of the bone-bearing
beds from which some fossils were extracted and preliminarily studied in the 1980s. This, together
with an exhaustive review of the literature, has showed that most of the previous age assignations
to those deposits were unfounded, as only the uppermost part of the section had been confidently
dated as middle/upper Permian. Additionally, from the middle part of the section, ichnites have
been discovered and described for the first time in the Permian of Menorca, recognising the
ichnogenera Hyloidichnus, purportedly produced by captorhinomorph eureptiles, in this case
probably moradisaurine captorhinids, and possibly Erpetopus, of acleistorhinid or nyctiphruretid
parareptile trackmakers. Two taxa of moradisaurines have also been identified by means of the
study of all the fossil bones from the middle part of the Cala del Pilar–Pla de Mar section present
in historical collections, which has been the main focus of the present work. The smallest of the
two has been identified as an indeterminate moradisaurine based on two bones collected from
different beds: a fragment of jaw with three rows of teeth, and an isolated dorsal vertebra with
typical characters of the group. The largest of the two taxa has been described as Balearosaurus
bombardensis gen. et sp. nov. based on a fragment of maxilla with at least three rows of bullet-
shaped teeth ornamented with ridges and furrows. Another relatively incomplete specimen
consisting of cranial, axial and appendicular bones has also been tentatively assigned to the same
species. Balearosaurus bombardensis gen. et sp. nov. was closely related to the large
moradisaurine reported from the neighbouring island of Mallorca, and those two were in turn
phylogenetically related to Rothianiscus, a genus of large moradisaurines from the lower–middle
Permian of southern North America. This, together with the distribution of all other known
moradisaurines, has allowed to put forward the hypothesis that the Variscan mountains were not
an important barrier to biogeographical dispersion of moradisaurines, because species of this
clade occurred on both sides of the mountains since the earliest members of the group. Moreover,
all known moradisaurines lived in palaeolatitudes between 30ºN and 30ºS, in regions where other
herbivorous groups more typical of temperate palaeolatitudes have rarely been reported. This
suggests that moradisaurines, together with caseids, may have been among the herbivores best
suited to thrive in the arid climates of the low latitudes of Pangaea, outcompeting the rest of
herbivorous groups until their demise in the late Permian.



7. Acknowledgements

We thank Antoni Obrador, Miquel Fernàndez, Enric Vicens and Joan Lluís Pretus for the
information about the original discovery of the tetrapod bone remains studied herein. To David
Gómez-Gras, Antoni Rodríguez-Perea, Eudald Mujal and Raül Carmona for the bibliography
provided and discussion on some aspects. To Miquel Fernàndez and Sebastià Matamalas for aid
in fieldwork. To Marina Rull and Xènia Aymerich for repreparation of the specimens. To Enric
Vicens for letting R.M.A. use the photographic equipment of the Palaeontology Unit of the
Universitat Autònoma de Barcelona. To William F. Simpson and Kenneth D. Angielczyk for the
pictures of vertebral material of moradisaurines housed in the Field Museum (Chicago). To
Daniela Schwarz, Florian Witzmann, Igmar Werneburg and Tom Hübner for access to the
materials of the collections of Museum für Naturkunde (Berlin), Eberhard Karls Universität
Tübingen (Tübingen) and Museum der Natur (Gotha), used here for comparison. To John A.
Nyakatura for giving to R.M.A. the raw CT scans of Orobates for comparison. To Henry S.
Sharpe for the illustration in Figure 8, funded with the grant 2112-2020-000001 of the Consell
Insular de Menorca granted to R.M.A., À.G. and J.F. To Neil Brocklehurst and Lorenzo
Marchetti, reviewers of this paper, for their thoughtful and constructive comments that improved
the original manuscript, and to the head editor Stig Walsh. We acknowledge support from the
CERCA program (Generalitat de Catalunya, Spain). R.M.A. was supported by the predoctoral
grant FPU17/01922 (Ministerio de Ciencia, Innovación y Universidades, Spain) and the grant
Synthesys+ DE-TAF-23 (European Commission). J.F. was supported by the Agencia Estatal de
Investigación (Spain) and the European Regional Development Fund AEI/FEDER EU, project
CGL2017-82654-P (European Union). J.F. is member of the consolidated research group 2017
SGR 086 GRC (Generalitat de Catalunya, Spain). O.O. and À.G. are members of the consolidated
research group 2017 SGR 1666 GRC (Generalitat de Catalunya, Spain).
8. Supplementary material

Supplementary material 1: Lithofacies descriptions (Supplementary Table 1) and detailed
stratigraphic log of Cala del Pilar–Pla de Mar section.

Supplementary material 2: Matrix data file (.nexus) used in the phylogenetic analysis.



9. References



Arche, A. & López-Gómez, J. 1992. Una nueva hipótesis sobre las primeras etapas de la evolución
        tectonosedimentaria de la cuenca pérmico-triásica del SE de la Cordillera Ibérica.
        Cuadernos de Geología Ibérica 16, 115–143.
Benton, M. J. 2008. When life nearly died. The greatest mass extinction of all time. Thames &
        Hudson: London.
Benton, M. J. & Twitchett, R. J. 2003. How to kill (almost) all life: the end-Permian extinction
        event. TRENDS in Ecology and Evolution 18(7), 358–365.
Benton, M. J. & Walker, A. D. 1985. Palaeoecology, taphonomy and dating of Permo-Triassic
        reptiles from Elgin, north-east Scotland. Palaeontology 28, 207–234.
Bercovici, A., Diez, J. B., Broutin, J., Bourquin, S., Linol, B., Villanueva-Amadoz, U., López-
        Gómez, J. & Durand, M. 2009. A palaeoenvirnomental analysis of Permian sediments in
        Minorca (Balearic Islands, Spain) with new palynological and megafloral data. Review of
        Palaeobotany and Palynology 158, 14–28.
Berman, D. S., Reisz, R. R. & Eberth, D. A. 1987. Seymouria sanjuanensis (Amphibia,
        Batrachosauria) from the Lower Permian Cutler Formation of north-central New Mexico
        and the occurrence of sexual dimorphism in that genus questioned. Canadian Journal of
        Earth Sciences 24, 1769–1784.
Berman, D. S., Sumida, S. S. & Martens, T. 1998. Diadectes (Diadectomorpha: Diadectidae) from
        the early Permian of Central Germany, with description of a new species. Annals of
        Carnegie Museum 67(1), 53–93.
Berman, D. S. & Sumida, S. S. 1995. New cranial material of the rare diadectid Desmatodon
        hesperis (Diadectomorpha) from the late Pennsylvanian of central Colorado. Annals of
        Carnegie Museum 64(4), 315–336.
Bernardi, M., Petti, F. M., Kustatscher, E., Franz, M., Hartkopf-Fröder, C., Labandeira, C. C.,
        Wappler, T., van Konijnenburg-van Cittert, J. H. A., Peecook, B. R. & Angielczyk, K. D.
        2017. Late Permian (Lopingian) terrestrial ecosystems: A global comparison with new
        data from the low-latitude Bletterbach Biota. Earth-Science Reviews 175, 18–43.
Borruel-Abadía, V., Barrenechea, J. F., Galán-Abellán, A. B., De la Horra, R., López-Gómez, J.,
        Ronchi, A., Luque, F. J., Alonso-Azcárate, J. & Marzo, M. 2019. Could acidity be the
        reason behind the Early Triassic biotic crisis on land? Chemical Geology 515, 77–86.
Bourquin, S., Bercovici, A., López-Gómez, J., Diez, J.B., Broutin, J., Ronchi, A., Durand, M.,
        Arché, A., Linol, B. & Amour, F. 2011. The Permian–Triassic transition and the onset of
        Mesozoic     sedimentation    at    the     northwestern     peri-Tethyan    domain    scale:
        Palaeogeographic     maps     and         geodynamic       implications.    Palaeogeography,
        Palaeoclimatology, Palaeoecology 299, 265–280.
Bourrouilh, R. 1973. Stratigraphie, sédimentologie et téctonique de l’île de Minorque et du Nord-
        Est de Majorque (Baléares). La terminaison nord-orientale des Cordilleres Bétiques en
        Méditerranée occidentale. State Ph.D. dissertation. Université Pierre & Marie Curie,
        Paris VI: Paris.
Bourrouilh, R. 1983. Estratigrafía, sedimentología y tectónica de la isla de Menorca y del noreste
        de Mallorca. Memorias del Instituto Geológico y Minero de España 99, 1–672 + 95 pl. +
        3 maps.
Brandes, C. & Tiedt, C. 1991. Petrographische Bestandsaufnahme der permotriassischen
        Sandsteine Menorcas (Balearen, westliches Mittelmeer). Neues Jahrbuch für Geologie
        und Paläontologie, Monatshefte 1991(4), 233–242.
Briere, P. R. 2000. Playa, playa lake, sabkha: Proposed definitions for old terms. Journal of Arid
        Environments 45(1), 1–7.
Brocklehurst, N. 2017. Rates of morphological evolution in Captorhinidae: an adaptive radiation
        of Permian herbivores. PeerJ 5:e3200, 1–25.
Brocklehurst, N. 2020. Olson's Gap or Olson's Extinction? A Bayesian tip-dating approach to
        resolving stratigraphic uncertainty. Proceedings of the Royal Society B 287, 20200154.
Brocklehurst, N., Dunne, E. M., Cashmore, D. D. & Fröbisch, J. 2018. Physical and
        environmental drivers of Paleozoic tetrapod dispersal across Pangaea. Nature
        Communications 9, 5216, 1–12.
Broutin, J., Ferrer, J., Gisbert, J. & Nmila, A. 1992. Permière découverte d’une microflore
        thuringienne dans le faciès saxonien de l’île de Minorque (Baléares, Espagne). Comptes
        Rendus de l’Académie des Sciences de Paris, s. 2 315, 117–122.
Buenaventura, A. 2004. Menorca, Atlas Náutico. Editorial Menorca S.A.: Maó.
Calafat, F. 1988. Estratigrafía y sedimentología de la litofacies Buntsandstein de Mallorca.
        Bachelor’s Thesis. Universitat de Barcelona: Barcelona.
Calafat, F., Fornós, J. J., Marzo, M., Ramos, E. & Rodríguez-Perea, A. 1986. Icnología de
        vertebrados de las facies Buntsandstein de Mallorca. In Cabrera, L. (ed.) XI Congreso
        Español de Sedimentología. Libro de Resúmenes, p. 40.
Calafat, F., Fornós, J. J., Marzo, M., Ramos-Guerrero, E. & Rodríguez-Perea, A. 1986–1987.
        Icnología de vertebrados de las facies Buntsandstein de Mallorca. Acta Geològica
        Hispànica 21–22, 515–520.
Carmona, R. 2004. Estudi d’un seimuriamorfe (Amphibia: Batrachosauria) del Permià superior
        de Menorca. Bachelor’s Thesis. Universitat de Barcelona: Barcelona.
Carroll, R. L., Kuhn, O. & Tatarinov, L. P. 1972. Teil 5B / Part 5B: Batrachosauria
        (Anthracosauria) Gephyrostegida–Chroniosuchida. In Kuhn, O. (ed.) Handbuch der
        Paläoherpetologie / Encyclopedia of Paleoherpetology. Gustav Fischer Verlag: Stuttgart
        and Portland.
Case, E. C. 1911. A revision of the Cotylosauria of North America. Carnegie Institution of
        Washington Publication 145, 1–121.
Case, E. C. & Williston, S. W. 1912. A description of the skills of Diadectes lentus and
        Animasaurus carinatus. American Journal of Science, 4th s. 33, 339–348.
Cisneros, J. C., Angielczyk, K., Kammerer, C. F., Smith, R. M. H., Fröbisch, J., Marsicano, C. A.
        & Richter, M. 2020a. Captorhinid reptiles from the lower Permian Pedra de Fogo
        Formation, Piauí, Brazil: the earliest herbivorous tetrapods in Gondwana. PeerJ 8:e8719,
        1–21.
Cisneros, J. C., Kammerer, C. F., Angielczyk, K. D., Fröbisch, J., Marsicano, C., Smith, R. M.,
        & Richter, M. 2020b. A new reptile from the lower Permian of Brazil (Karutia fortunata
        gen. et sp. nov.) and the interrelationships of Parareptilia. Journal of Systematic
        Palaeontology 18(23), 1939–1959.
Citton, P., Ronchi, A., Maganuco, S., Caratelli, M., Nicosia, U., Sacci, E. & Romano, M. 2019.
        First tetrapod footprints from the Permian of Sardinia and their palaeontological and
        stratigraphical significance. Geological Journal 54(4), 2084–2098.
Contessi, M., Voigt, S. & Bibonne, R. 2018. Permian Tetrapod Footprints from Tunisia. Ichnos
        25, 119–127.
Cope, E. D. 1896. The reptilian order Cotylosauria. Proceedings of the American Philosophical
        Society 34, 436–457.
Crespí, D. & Merino, A. 1998. Contribució al coneixement de les mines de coure situades en el
        Permo-Trias de Menorca. Endins 22, 119–123.
Day, M. O., Ramezani, J., Bowring, S. A., Sadler, P. M., Erwin, D. H., Abdala, F. & Rubidge, B.
        S. 2015. When and how did the terrestrial mid-Permian mass extinction occur? Evidence
        from the tetrapod record of the Karoo Basin, South Africa. Proceedings of the Royal
        Society B 282, 20150834.
deBraga, M., Mevitt, J. & Reisz, R. R. 2019. A new captorhinid from the Permian Cave System
        near Richards Spur, Oklahoma and the taxic diversity of Captorhinus at this locality.
        Frontiers in Earth Science 7:112, 1–19.
Dodick, J. T. & Modesto, S. P. 1995. The cranial anatomy of the captorhinid reptile
        Labidosaurikos meachami from the lower Permian of Oklahoma. Palaeontology 38(3),
        687–711.
Dutuit, J. M. 1976. Il est probable que les Rhynchocéphales sont représentés dans la faune du
        Trias marocain. Compte-Rendus de l’Académie des Sciences, Paris 238, 483–486.
Erwin, D. H. 1994. The Permo–Triassic extinction. Nature 367, 231–236.
Falkingham, P. L. 2012. Acquisition of high resolution three-dimensional models using free,
        open-source, photogrammetric software. Palaeontologia Electronica 15(1), 1T:15p.
Franzel, M., Jones, S. J., Meadows, N., Allen, M. B., McCaffrey, K. & Morgan, T. 2020. Basin-
        scale fluvial correlation and response to the Tethyan marine transgression: An example
        from the Triassic of central Spain. Basin Research 33(1), 1–25.
Gand, G. 1988. Les traces de vertébrés tétrapodes du Permien français: paléontologie,
        stratigraphie, paléoenvironnements. Ph.D. dissertation. Université de Bourgogne: Dijon.
Gand, G. 1993. La palichnofaune de vertébrés tétrapodes du basin permien de Saint-Affrique
        (Aveyron): comparaisons et conséquences stratigraphiques. Géologie de la France 1, 41–
        56.
Gand, G., Kerp, H., Parsons, C. & Martínez-García, E. 1997. Palaeoenvironmental and
        stratigraphic aspects of animal traces and plant remains in Spanish Permian red beds
        (Peña Sagra, Cantabrian Mountains, Spain). Geobios 30(2), 295–318.
Gand, G., Garric, J., Demathieu, G. & Ellenberger, P. 2000. La palichnofaune de vertébrés
        tétrapodes du Permien superiéur du bassin de Lodève (Languedoc-France).
        Palaeovertebrata 29, 1–82.
Gand, G., De La Horra, R., Galán-Abellán, B., López-Gómez, J., Barrenechea, J. F., Arche, A. &
        Benito, M. I. 2010. New ichnites from the Middle Triassic of the Iberian Ranges (Spain):
        palaeoenvironmental and paleogeographical implications. Historical Biology 22(1–3),
        40–56.
Gand, G., Tüysüz, O., Steyer, J. S., Allain, R., Sakınç, M., Sanchez, S., Șengör, A. M. C. & Sen,
        S. 2011. New Permian tetrapod footprints and macroflora from Turkey (Çakraz
        Formation,   northwestern    Anatolia):   Biostratigraphic   and   palaeoenvironmental
        implications. Comptes Rendus Palevol 10, 617–625.
Gand, G. & Durand, M. 2006. Tetrapod footprint ichno-associations from French Permian basins.
        Comparisons with other Euramerican ichnofaunas. Geological Society, London, Special
        Publications 265, 157–177.
Gilmore, C. W. 1927. Fossil footprints of the Grand Canyon: second contribution. Smithsonian
        Miscellaneous Collections 80(3), 1–78 + 21 pls.
Gómez-Gras, D. M. 1987. Estratigrafía física y petrología sedimentaria del Pérmico y
       Buntsandstein de la isla de Menorca. Bachelor’s Thesis. Universitat Autònoma de
       Barcelona: Barcelona.
Gómez-Gras, D. M. 1992. El Permotrías de las Baleares, de la Cordillera Costero Catalana y de
       la vertiente mediterránea de la Cordillera Ibérica: Facies y Petrología Sedimentaria.
       Ph.D. dissertation. Universitat Autònoma de Barcelona: Barcelona.
Gómez-Gras, D. 1993. El Permotrías de las Baleares y de la vertiente mediterránea de la
       Cordillera Ibérica y del Maestrat: Facies y Petrología Sedimentaria (Parte II). Boletín
       Geológico y Minero 104–105, 467–515.
Gómez-Gras, D. & Alonso-Zarza, A. M. 2003. Reworked calcretes: their significance in the
       reconstruction of alluvial sequences (Permian and Triassic, Minorca, Balearic Islands,
       Spain). Sedimentary Geology 158, 299–319.
Hasiotis, S. T., Platt, B. F., Hembree, D. I. & Everhart, M. J. 2007. The Trace-Fossil Record of
       Vertebrates. In William Miller, III (ed.) Trace Fossils: Concepts, Problems, Prospects,
       196–218. Elsevier.
Haubold, H. 2000. Tetrapodenfährten aus dem Perm – Kenntnisstand und Progress 2000.
       Hallesches Jahrbuch für Geowissenschaften, B 22, 1–16.
Haubold, H., Hunt, A. P., Lucas, S. G. & Lockley, M. G. 1995. Wolfcampian (Early Permian)
       vertebrate tracks from Arizona and New Mexico. New Mexico Museum of Natural History
       and Science Bulletin 6, 135–165.
Hermite, H. 1879. Études géologiques sur les îles Baléares. Première partie: Majorque et
       Minorque. Pichon et Savy: Paris.
Hermite, H. 1888. Estudios Geológicos de las Islas Baleares. Boletín de la Comisión del Mapa
       Geológico 15, 1–244 + 4 pl.
Heyler, D. & Lessertisseur, J. 1963. Pistes de tétrapodes Permiens dans la région de Lodève
       (Hérault). Muséum National d'Histoire Naturelle, C 11(2), 1–100.
Hmich, D., Schneider, J. W., Saber, H., Voigt, S. & El Wartiti, M. 2006. New continental
       Carboniferous and Permian faunas of Morocco: implications for biostratigraphy,
       palaeobiogeography      and   palaeoclimate.   Geological   Society,   London,   Special
       Publications 265, 297–324.
Hminna, A., Voight, A., Saber, H., Schneider, J. W. & Hmich, D. 2012. On a moderately diverse
       continental ichnofauna from the Permian Ikakern Formation (Argana Basin, Western
       High Atlas, Morocco). Journal of African Earth Sciences 68, 15–23.
Holmes, R. B. 2003. The hind limb of Captorhinus aguti and the step cycle of basal amniotes.
       Canadian Journal of Earth Sciences 40, 515–526.
Ivakhnenko, M. F. 2008. Podklass Captorhinomorpha [Subclass Captorhinomorpha]. In
       Ivakhnenko, M. F. & Kurotchkin, E. N. (eds) Iskopaemye pozvonotchnye Rossii i
        sopredel'nykh stran: Iskopaemye reptilii i ptitsy, Tchast' 1 [Fossil vertebrates of Russia
        and adjacent countries: Fossil reptiles and birds, Part 1], 86–94. GEOS: Moskva.
Jalil, N. E. & Dutuit, J. M. 1996. Permian captorhinid reptiles from the Argana Formation,
        Morocco. Palaeontology 39, 907–918.
Jung, J. P. & Sumida, S. S. 2017. A juvenile of the multiple-tooth-rowed reptile Labidosaurikos
        (Eureptilia, Captorhinidae, Moradisaurinae) from the Lower Permian of north-central
        Texas. PaleoBios 34, 1–5.
Kissel, R. 2010. Morphology, phylogeny, and evolution of Diadectidae (Cotylosauria:
        Diadectomorpha). Ph.D. dissertation. University of Toronto: Toronto.
Kuhn, O. 1961. Pars 99. Reptilia (Supplementum 1(2)). In Westphal, F. (ed.) Fossilium
        Catalogus. I: Animalia. Uitgeverij Dr. W. Junk: The Hague, Netherlands.
Kuhn, O. 1969. Teil 6 / Part 6: Cotylosauria. In Kuhn, O. (ed.) Handbuch der Paläoherpetologie
        / Encyclopedia of Paleoherpetology. Gustav Fischer Verlag: Stuttgart and Portland.
LeBlanc, A. R. H., Brar, A. K., May, W. & Reisz, R. R. 2015. Multiple tooth-rowed captorhinids
        from the early Permian fissure fills of the Bally Mountain Locality of Oklahoma.
        Vertebrate Anatomy Morphology Palaeontology 1(1), 35–49.
LeBlanc, A. R. H. & Reisz, R. R. 2015. Patterns of tooth development and replacement in
        captorhinid reptiles: a comparative approach for understanding the origin of multiple
        tooth rows. Journal of Vertebrate Paleontology 35(3), e919928, 1–13.
Leonardi, G. 1987. Glossary and Manual of Tetrapod Footprint Palaeoichnology. Departamento
        Nacional de Produção Mineral: Brasília.
Liebrecht, T., Fortuny, J., Galobart, À., Müller, J. & Sander, P. M. 2017. A large, multiple-tooth-
        rowed captorhinid reptile (Amniota: Eureptilia) from the Upper Permian of Mallorca
        (Balearic Islands, Western Mediterranean). Journal of Vertebrate Paleontology 37(1),
        e1251936, 1–6.
Linol, B., Bercovici, A., Bourquin, S., Diez, J. B., López-Gómez, J., Broutin, J., Durand, M. &
        Villanueva-Amadoz, U. 2009. Late Permian to Middle Triassic correlations and
        palaeogeographical     reconstructions    in   south-western     European     basins:   New
        sedimentological data from Minorca (Balearic Islands, Spain). Sedimentary Geology 220,
        77–94.
Llull, B. & Perelló, L. 2013. La mineria de coure a Menorca. De la prehistòria a l’actualitat. Bolletí
        de la Societat Arqueològica Lul·liana. Revista d'Estudis Històrics 69, 75–93.
Logghe, A., Mujal, E., Marchetti, L., Nel, A., Pouillon, J.-M., Giner, S., Garrouste, R. & Steyer,
        J.-S. 2021. Hyloidichnus trackways with digit and tail drag traces from the Permian of
        Gonfaron (Var, France): New insights on the locomotion of captorhinomorph eureptiles.
        Palaeogeography,             Palaeoclimatology,            Palaeoecology,            110436.
        https://doi.org/10.1016/j.palaeo.2021.110436
López-Gómez, J., Alonso-Azcárate, J., Arche, A., Arribas, J., Fernández-Barrenechea, J.,
       Borruel-Abadía, V., Bourquin, S., Cadenas, P., Cuevas, J., De la Horra, R., Díez, J. B.,
       Escudero-Mozo, M. J., Fernández-Viejo, G., Galán-Abellán, B., Galé, C., Gaspar-
       Escribano, J., Gisbert-Aguilar, J., Gómez-Gras, D., Goy, A., Gretter, N., Heredia-
       Carballo, N., Lago, M., Lloret, J., Luque, J., Márquez, L., Márquez-Aliaga, A., Martín-
       Algarra, A., Martín-Chivelet, J., Martín-González, F., Marzo, M., Mercedes-Martín, R.,
       Ortí, F., Pérez-López, A., Pérez-Valera, F., Pérez-Valera, J. A., Plasencia, P., Ramos, E.,
       Rodríguez-Méndez, L., Ronchi, A., Salas, R., Sánchez-Fernández, D., Sánchez-Moya,
       Y., Sopeña, A., Suárez-Rodríguez, Á., Tubía, J. M., Ubide, T., Valero-Garcés, B., Vargas,
       H. & Viseras, C. 2019a. Permian-Triassic rifting stage. In Vergés, J. & Kullberg, J. C.
       (coords) The Geology of Iberia: A Geodynamic Approach. Volume 3: The Alpine Cycle,
       29–112. Springer: Cham.
López-Gómez, J., Martín-González, F., Heredia, N., De la Horra, R., Barrenechea, J. F., Cadenas,
       P., Juncal, M., Diez, J. B., Borruel-Abadía, V., Pedreira, D., García-Sansegundo, J.,
       Farias, P., Galé, C., Lago, M., Ubide, T., Fernández-Viejo, G. & Gand, G. 2019b. New
       lithostratigraphy for the Cantabrian Mountains: a common tectono-stratigraphic evolution
       for the onset of the Alpine cycle in the W Pyrenean realm, N Spain. Earth-Science
       Reviews 188, 249–271.
López-Gómez, J. & Arche, A. 1987. Evolución sedimentológica de la Unidad «Limos y areniscas
       de Alcotas». Tramo medio de la Facies Buntsandstein del sector SE de la Rama Castellana
       de la Cordillera Ibérica (Provincias de Cuenca y Valencia). Acta Geològica Hispànica
       21–22, 9–18.
López-Gómez, J. & Arche, A. 1992. Las unidades litoestratigráficas del Pérmico y Triásico
       Inferior y Medio en el sector SE de la Cordillera Ibérica. Estudios Geológicos 48, 123–
       143.
Lucas, S. G. 2019. An ichnological perspective on some major events of Paleozoic tetrapod
       evolution. Bollettino della Società Paleontologica Italiana 58(3), 223–266.
Lucas, S. G., Krainer, K., Chaney, D. S., DiMichele, W. A., Voigt, S., Berman, D. S. & Henrici,
       A. C. 2013. The Lower Permian Abo Formation in Central New Mexico. New Mexico
       Museum of Natural History and Science Bulletin 59, 161–180.
Mack, G. H., James, W. C. & Monger, H. C. 1993. Classification of paleosols. Geological Society
       of America Bulletin 105, 129–136.
Marchetti, L. 2016. New occurrences of tetrapod ichnotaxa from the Permian Orobic Basin
       (Northern Italy) and critical discussion of the age of the ichnoassociation. Papers in
       Palaeontology 2(3), 363–386.
Marchetti, L., Avanzini, M. & Conti, M. A. 2013. Hyloidichnus bifurcatus Gilmore, 1927 and
        Limnopus heterodactylus (King, 1845) from the Early Permian of Southern Alps (N
        Italy): A New Equilibrium in the Ichnofauna. Ichnos 20, 202–217.
Marchetti, L., Santi, G. & Avanzini, M. 2014. The problem of small footprints in paleoichnology:
        remarks on the early Permian ichnotaxon Erpetopus cassinsi, a local species from
        southern Alps (northern Italy). Rivista Italiana di Paleontologia e Stratigrafia 120(2),
        129–143.
Marchetti, L., Ronchi, A., Santi, G., Schirolli, P. & Conti, M. A. 2015a. Revision of a classic site
        for Permian tetrapod ichnology (Collio Formation, Trompia and Caffaro valleys, N.
        Italy), new evidences for the radiation of captorhinomorph footprints. Palaeogeography,
        Palaeoclimatology, Palaeoecology 433, 140–155.
Marchetti, L., Ronchi, A., Santi, G. & Voigt, S. 2015b. The Gerola Valley site (Orobic Basin,
        Northern Italy): A key for understanding late Early Permian tetrapod ichnofaunas.
        Palaeogeography, Palaeoclimatology, Palaeoecology 439, 97–116.
Marchetti, L., Forte, G., Bernardi, M., Wappler, T., Hartkopf-Fröder, C., Krainer, K. &
        Kustatscher, E. 2015c. Reconstruction of a Late Cisuralian (Early Permian) floodplain
        lake environment: Palaeontology and sedimentology of the Tregiovo Basin (Trentino–
        Alto Adige, Northern Italy). Palaeogeography, Palaeoclimatology, Palaeoecology 440,
        180–220.
Marchetti, L., Belvedere, M., Voigt, S., Klein, H., Castanera, D., Díaz-Martínez, I., Marty, D.,
        Xing, L., Feola, S., Melchor, R.N. & Farlow, J. O. 2019b. Defining the morphological
        quality of fossil footprints. Problems and principles of preservation in tetrapod ichnology
        with examples from the Palaeozoic to the present. Earth-Science Reviews 193, 109–145.
Marchetti, L., Klein, H., Buchwitz, M., Ronchi, A., Smith, R. M. H., De Klerk, W. J., Sciscio, L.
        & Groenewald, G. H. 2019c. Permian-Triassic vertebrate footprints from South Africa:
        Ichnotaxonomy, producers and biostratigraphy through two major faunal crises.
        Gondwana Research 72, 139–168.
Marchetti, L., Voigt, S., Lucas, S. G., Francischini, H., Dentzien-Dias, P., Sacchi, R., Mangiacotti,
        M., Scali, S., Gazzola, A., Ronchi, A. & Millhouse, A. 2019a. Tetrapod ichnotaxonomy
        in eolian paleoenvironments (Coconino and De Chelly formations, Arizona) and late
        Cisuralian (Permian) sauropsid radiation. Earth-Science Reviews 190, 148–170.
Marchetti, L., Voigt, S., Lucas, S.G., Stimson, M.R., King, O.A. & Calder, J.H. 2020a. Footprints
        of the earliest reptiles: Notalacerta missouriensis – Ichnotaxonomy, potential
        trackmakers, biostratigraphy, palaeobiogeography and palaeoecology. Annales Societatis
        Geologorum Poloniae 90, 271–290.
Marchetti, L., Voigt, S., Mujal, E., Lucas, S.G., Francischini, H., Fortuny, J. & Santucci, V.L.
        2020b. Extending the footprint record of Pareiasauromorpha to the Cisuralian: earlier
        appearance and wider palaeobiogeography of the group. Papers in Palaeontology 2020,
        1–23.
Martí, J., Paniello, X., Pomar, L., Ramos, E. & Rodríguez-Perea, A. 1985. El Triásico de las
        Baleares. In Mateu Ibars, F. & Marzo, M. (eds) II Coloquio de Estratigrafía y
        Paleogeografía del Pérmico y Triásico de España, 84–85. La Seu d’Urgell, 23–25
        Septiembre 1985. Libro de Resúmenes.
Martin-Closas, C. & Ramos, E. 2005. Palaeogene Charophytes of the Balearic Islands (Spain).
        Geologica Acta 3(1), 39–58.
Matamales-Andreu, R., Fortuny, J., Mujal, E. & Galobart, À. 2019. Tetrapod tracks from the
        Permian of Mallorca (western Mediterranean): preliminary data, biostratigraphic and
        biogeographic inferences. In The Palaeontological Association, 63rd annual meeting,
        15th–21st December 2019, 107.
Melchor, R. N. & Sarjeant, W. A. S. 2004. Small amphibian and reptile footprints from the
        Permian Carapacha Basin, Argentina. Ichnos 11, 57–78.
Meyer, H. von 1860. Phanerosaurus Naumanni ans dem Sandstein des Rothliegenden in
        Deutschland. Paleontographica 7, 248–252 + pl. 27.
Miall, A. D. 1985. Architectural-Element Analysis: a new method of facies analysis applied to
        fluvial deposits. Earth-Science Reviews 22, 261–308.
Miall, A. D. 2006. The Geology of Fluvial Deposits: Sedimentary Facies, Basin Analysis, and
        Petroleum Geology. 4th ed. Springer: Berlin, Heidelberg, New York.
Michel, L.A., Tabor, N.J., Montañez, I.P., Schmitz, M.D. & Davydov, V.I. 2015.
        Chronostratigraphy and Paleoclimatology of the Lodève Basin, France: Evidence for a
        pan-tropical   aridification   event   across   the   Carboniferous–Permian    boundary.
        Palaeogeography, Palaeoclimatology, Palaeoecology 430, 118–131.
Modesto, S. P., Scott, D. M., Berman, D. S., Müller, J. & Reisz, R. R. 2007. The skull and the
        palaeoecological significance of Labidosaurus hamatus, a captorhinid reptile from the
        Lower Permian of Texas. Zoological Journal of the Linnean Society 149, 237–262.
Modesto, S. P., Lamb, A. J. & Reisz, R. R. 2014. The captorhinid reptile Captorhinikos valensis
        from the lower Permian Vale Formation of Texas, and the evolution of herbivory in
        eureptiles. Journal of Vertebrate Paleontology 34(2), 291–302.
Modesto, S. P., Flear, V. J., Dilney, M. M. & Reisz, R. R. 2016. A large moradisaurine tooth plate
        from the lower Permian of Texas and its biostratigraphic implications. Journal of
        Vertebrate Paleontology 36(6), e1221832, 1–4.
Modesto, S. P., Scott, D. & Reisz, R. R. 2018. A new small captorhinid reptile from the lower
        Permian of Oklahoma and resource partitioning among small captorhinids in the Richards
        Spur fauna. Papers in Palaeontology 4(2), 293–307.
Modesto, S. P., Richards, C. D., Ide, O. & Sidor, C. A. 2019. The vertebrate fauna of the upper
        Permian of Niger — X. The mandible of the captorhinid reptile Moradisaurus grandis.
        Journal of Vertebrate Paleontology 38(6), e1531877, 1–14.
Moodie, R. L. 1929. Vertebrate footprints from the Red Beds of Texas. American Journal of
        Science 97, 352–368.
Moreau, J.-D., Benaouiss, N., Tourani, A., Steyer, J.-S., Laurin, M., Peyer, K., Béthoux, O.,
        Aouda, A. & Jalil, N.-E. 2020. A new ichnofauna from the Permian of the Zat Valley in
        the Marrakech High Atlas of Morocco. Journal of African Earth Sciences 172, 103973,
        1–14.
Mujal, E., Fortuny, J., Oms, O., Bolet, A., Galobart, À. & Anadón, P. 2016. Palaeoenvironmental
        reconstruction and early Permian ichnoassemblage from the NE Iberian Basin (Pyrenean
        Basin). Geological Magazine 153(4), 578–600.
Mujal, E., Fortuny, J., Pérez-Cano, J., Dinarès-Turell, J., Ibáñez-Insa, J., Oms, O., Vila, I., Bolet,
        A. & Anadón, P. 2017. Integrated multi-stratigraphic study of the Coll de Terrers late
        Permian–Early Triassic continental succession from the Catalan Pyrenees (NE Iberian
        Peninsula): A geologic reference record for equatorial Pangaea. Global and Planetary
        Change 159, 46–60.
Mujal, E., Marchetti, L., Schoch, R. R. & Fortuny, J. 2020. Upper Paleozoic to lower Mesozoic
        tetrapod ichnology revisited: photogrammetry and relative depth pattern inferences on
        functional prevalence of autopodia. Frontiers in Earth Science 8:248, 1–23.
Müller, J. & Reisz, R. R. 2005. An early captorhinid reptile (Amniota, Eureptilia) from the Upper
        Carboniferous of Hamilton, Kansas. Journal of Vertebrate Paleontology 25(3), 561–568.
Nyakatura, J. A., Allen, V. R., Lauströer, J., Andikfar, A., Danczak, M., Ullrich, H.-J., Hufenbach,
        W., Martens, T. & Fischer, M. S. 2015. A three-dimensional skeletal reconstruction of
        the stem amniote Orobates pabsti (Diadectidae): analyses of body mass, centre of mass
        position, and joint mobility. PLoS ONE 10(9), e0137284, 1–20.
O’Keefe, F. R., Sidor, C. A., Larsson, H. C., Maga, A. & Ide, O. 2005. The vertebrate fauna of
        the upper Permian of Niger—III, Morphology and ontogeny of the hindlimb of
        Moradisaurus grandis (Reptilia, Captorhinidae). Journal of Vertebrate Paleontology
        25(2), 309–319.
Olroyd, S. L. & Sidor, C. A. 2017. A review of the Guadalupian (middle Permian) global tetrapod
        fossil record. Earth-Science Reviews 171, 583–597.
Olson, E. C. 1947. The family Diadectidae and its bearing on the classification of reptiles.
        Fieldiana: Geology 11(1), 1–53.
Olson, E. C. 1954. Fauna of the Vale and Choza: 9. Captorhinomorpha. Fieldiana: Geology
        10(19), 211–218.
Olson, E. C. 1962a. Late Permian terrestrial vertebrates, U.S.A. and U.S.S.R. Transactions of the
        American Philosophical Society 52(2), 1–224.
Olson, E. C. 1962b. Permian vertebrates from Oklahoma and Texas. Part II. — The osteology of
        Captorhinikos chozaensis Olson. Oklahoma Geological Survey Circular 59, 49–68.
Olson, E. C. 1965. New Permian vertebrates from the Chickasha Formation in Oklahoma.
        Oklahoma Geological Survey Circular 70, 1–70.
Olson, E. C. 1970. New and little known genera and species of vertebrates from the Lower
        Permian of Oklahoma. Fieldiana: Geology 18(3), 359–434.
Olson, E. C. 1979. Seymouria grandis n. sp. (Batrachosauria: Amphibia) from the middle Clear
        Fork (Permian) of Oklahoma and Texas. Journal of Paleontology 53(3), 720–728.
Olson, E. C. & Beerbower, J. R. 1953. The San Angelo Formation, Permian of Texas, and its
        vertebrates. The Journal of Geology 61(5), 389–423.
Olson, E. C. & Barghusen, H. 1962. Permian vertebrates from Oklahoma and Texas. Part I. —
        Vertebrates from the Flowerpot Formation, Permian of Oklahoma. Oklahoma Geological
        Survey Circular 59, 4–48.
Pomar-Gomà, L. 1979. The Triassic of the Balearic Islands. Geology Department, Palma de
        Mallorca University: Palma.
Postma, G. 1990. Depositional architecture and facies of river and fan deltas: a synthesis. In
        Colella, A. & Prior, D. B. (eds.) Coarse-Grained Deltas. Special Publications of the
        International Association of Sedimentologists 10, 13–27.
Pretus, J. Ll. & Obrador, A. 1987. Presencia de restos óseos en el Pérmico de Menorca (nota
        previa). Bolletí de la Societat d’Història Natural de Balears 31, 149–152.
Ramos, A. & Doubinger, J. 1989. Premières datations palynologiques dans le facies
        Buntsandstein de l’île de Majorque (Baléares, Espagne). Comptes Rendus de l’Académie
        des Sciences de Paris, s. 2 309, 1089–1094.
Reisz, R. R., Liu, J., Li, J.-L. & Müller, J. 2011. A new captorhinid reptile, Gansurhinus
        qingtoushanensis, gen. et sp. nov., from the Permian of China. Naturwissenschaften 98,
        435–441.
Reisz, R. R., Haridy, Y. & Müller, J. 2016. Euconcordia nom. nov., a replacement name for the
        captorhinid eureptile Concordia Müller and Reisz, 2005 (non Kingsley, 1880), with new
        data on its dentition. Vertebrate Anatomy Morphology Palaeontology 3, 1–6.
Reisz, R. R., MacDougall, M. J., LeBlanc, A. R. H., Scott, D. & Nagesan, R. S. 2020. Lateralized
        feedins behaviour in a Paleozoic reptile. Current Biology 30, 2374–2378.
Reisz, R. R. & Sues, H.-D. 2000. Herbivory in late Paleozoic and Triassic terrestrial vertebrates.
        In Sues, H.-D. (ed) Evolution of Herbivory in Terrestrial Vertebrates, 9–41. Cambridge
        University Press.
Ricqlès, A. de & Bolt, J. R. 1983. Jaw growth and tooth replacement in Captorhinus aguti
        (Reptilia: Captorhinomorpha): a morphological and histological analysis. Journal of
        Vertebrate Paleontology 3(1), 7–24.
Ricqlès, A. de & Taquet, P. 1982. La faune de vertébrés du Permien Supérieur du Niger. I. Le
        captorhinomorphe Moradisaurus grandis (Reptilia, Cotylosauria). Le crane. Annales de
        Paléontologie (Vert.-Invert.) 68, 33–106.
Rodríguez-Perea, A., Ramos-Guerrero, E., Pomar, L., Paniello, X., Obrador, A. & Martí, J. 1987.
        El Triásico de las Baleares. Cuadernos de Geología Ibérica 11, 295–321.
Romano, M. & Rubidge, B. 2019. Long bone scaling in Captorhinidae: do limb bones scale
        according to elastic similarity in sprawling basal amniotes? Lethaia 52(3), 389–402.
Rosell, J., Arribas, J., Elízaga, E. & Gómez-Gras, D. 1988. Caracterización sedimentológica y
        petrográfica de la serie roja permo–triásica de la isla de Menorca. Boletín Geológico y
        Minero 99(1), 71–82.
Rosell, J., Gómez-Gras, D. & Elízaga, E. 1989a. Mapa Geológico de España. Escala 1:25.000.
        Isla de Menorca. Cap Menorca y Ciutadella. Segunda serie, primera edición. Instituto
        Tecnológico GeoMinero de España: Madrid.
Rosell, J., Gómez-Gras, D. & Elízaga, E. 1989b. Mapa Geológico de España. Escala 1:25.000.
        Isla de Menorca. Cala en Brut i Alaior. Segunda serie, primera edición. Instituto
        Tecnológico GeoMinero de España: Madrid.
Sàbat, F., Gelabert, B. & Rodríguez-Perea, A. 2018. Minorca, an exotic Balearic island (western
        Mediterranean). Geologica Acta 16(4), 411–426.
Santi, G., Marchetti, L., Schirolli, P. & Ronchi, A. 2020. The Cisuralian tetrapod ichnoassociation
        from Italy: from historical findings to a standard reference status. Journal of
        Mediterranean Earth Sciences 12, 39–59.
Scotese, C. R. 2014. Atlas of Middle & Late Permian and Triassic Paleogeographic Maps, maps
        43 – 48 from Volume 3 of the PALEOMAP Atlas for ArcGIS (Jurassic and Triassic) and
        maps 49 – 52 from Volume 4 of the PALEOMAP Atlas for ArcGIS (Late Paleozoic),
        Mollweide Projection, PALEOMAP Project: Evanston, IL, USA.
Schneider, J. W., Lucas, S. G., Scholze, F., Voigt, S., Marchetti, L., Klein, H., Opluštil, S.,
        Werneburg, R., Golubevb, V. K., Barrick, J. E., Nemyrovska, Y., Ronchil, A., Day, M.
        O., Silantiev, V. V., Rößler, R., Saber, H., Linnemann, U., Zharinova, V. & Shen, S.-Z.
        2020. Late Paleozoic–early Mesozoic continental biostratigraphy — Links to the
        Standard Global Chronostratigraphic Scale. Palaeoworld 29(2), 186–238.
Sennikov, A. G., & Golubev, V. K. 2017. Sequence of Permian tetrapod faunas of Eastern Europe
        and the Permian–Triassic ecological crisis. Paleontological Journal 51(6), 600–611.
Sidor, C. A., O’Keefe, F. R., Damiani, R., Steyer, J. S., Smith, R. M. H., Larsson, H. C. E., Sereno,
        P. C., Ide, O. & Maga, A. 2005. Permian tetrapods from the Sahara show climate-
        controlled endemism in Pangaea. Nature 434, 886–889.
Smith, R. M., Sidor, C. A., Tabor, N. J. & Steyer, J.-S. 2015. Sedimentology and vertebrate
        taphonomy of the Moradi Formation of northern Niger: A Permian wet desert in the
        tropics of Pangaea. Palaeogeography, Palaeoclimatology, Palaeoecology 440, 128–141.
Speksnijder, A. 1985. Anatomy of a strike-slip fault controlled sedimentary basin, Permian of the
        southern Pyrenees, Spain. Sedimentary Geology 44, 179–223.
Stappenbeck, R. 1905. Über Stephanospondylus n. g. und Phanerosaurus H. v. Meyer. Zeitschrift
        der Deutschen Geologischen Gesellschaft 57, 380–437.
Stovall, J. W. 1950. A new cotylosaur from North Central Oklahoma. American Journal of
        Science 248(1), 46–54.
Sullivan, C. & Reisz, R. R. 1999. First record of Seymouria (Vertebrata: Seymouriamorpha) from
        Early Permian fissure fills at Richards Spur, Oklahoma. Canadian Journal of Earth
        Sciences 36, 1257–1266.
Sumida, S. S. 1990. Vertebral morphology, alternation of neural spine height, and structure in
        Permo-Carboniferous tetrapods, and a reappraisal of primitive modes of terrestrial
        locomotion. University of California Publications in Zoology 122, 1–129 + 3 pls.
Swofford, D. L. 2003. PAUP*. Phylogenetic Analysis Using Parsimony (*and Other Methods).
        Version 4. Sinauer Associates: Sunderland, Massachusetts.
Tabor, N. J. & Poulsen, C. J. 2008. Palaeoclimate across the Late Pennsylvanian–Early Permian
        tropical palaeolatitudes: A review of climate indicators, their distribution, and relation to
        palaeophysiographic       climate    factors.    Palaeogeography,       Palaeoclimatology,
        Palaeoecology 268(3–4), 293–310.
Taquet, P. 1969. Première découverte en Afrique d’un reptile captorhinomorphe (cotylosaurien).
        Comptes Rendus Hebdomadaires des Séances de l'Academie des Sciences Paris, s. D 268,
        779–781.
Vera, J.-A., Alonso-Chaves, F. M., Andreo, B., Arias, C., Azañón, J. M., Balanyá, J. C., Barón,
        A., Booth-Rea, G., Castro, J. M., Chacón, B., Company, M., Crespo-Blanc, A., Delgado,
        F., Díaz de Federico, A., Esteras, M., Estévez, A., Fernández, J., Fornós, J. J., Galindo-
        Zaldívar, J., García-Casco, A., García-Dueñas, V., García-Hernández, M., Garrido, C. J.,
        Gea, G. A. de, Gelabert, B., Gervilla, F., González-Lodeiro, F., Jabaloy, A., López-
        Garrido, A. C., Luján, M., Martín-Algarra, A., Martín-Chivelet, J., Martín-Martín, M.,
        Molina, J. M., Morata, D., Nieto, J. M., Obrador, A., O’Dogherty, L., Orozco, M., Pérez-
        López, A., Pomar, L., Puga, E., Ramos, E., Rey, J., Rivas, P., Rodríguez-Cañero, R., Ruiz-
        Cruz, M. D., Ruiz-Ortiz, P. A., Sàbat, F., Sánchez-Gómez, M., Sánchez-Navas, A.,
        Sandoval, J., Sanz de Galdeano, C., Soto, J. I., Torres-Roldán, R. L. & Villas, L. 2004.
       Capítulo 4. Cordillera Bética y Baleares. In Vera, J.-A. (ed.) Geología de España, 345–
       464. Instituto Tecnológico GeoMinero de España: Madrid.
Viglietti, P. A., Smith, R. M., Angielczyk, K. D., Kammerer, C. F., Fröbisch, J., & Rubidge, B.
       S. 2016. The Daptocephalus Assemblage Zone (Lopingian), South Africa: a proposed
       biostratigraphy based on a new compilation of stratigraphic ranges. Journal of African
       Earth Sciences 113, 153–164.
Vjushkov, B. P. & Chudinov, P. K. 1957. Otkrytie Kaptorinid v verkhnnej Permi SSSR
       [Discovery of a captorhinid in the upper Permian of the USSR]. Doklady Akademii Nauk
       SSSR 112(3), 523–536.
Voigt, S. 2005. Die Tetrapodenichnofauna des kontinentalen Oberkarbon und Perm im Thüringer
       Wald - Ichnotaxonomie, Paläoökologie und Biostratigraphie. Cuvillier Verlag:
       Göttingen.
Voigt, S., Hminna, A., Saber, H., Schneider, J. W. & Klein, H. 2010. Tetrapod footprints from
       the uppermost level of the Permian Ikakern Formation (Argana Basin, Western High
       Atlas, Morocco). Journal of African Earth Sciences 57, 470–478.
Voigt, S., Lagnaoui, A., Hminna, A., Saber, H. & Schneider J. W. 2011. Revisional notes on the
       Permian tetrapod ichnofauna from the Tiddas Basin, central Morocco. Palaeogeography,
       Palaeoclimatology, Palaeoecology 302, 474–483
Voigt, S. & Haubold, H. 2015. Permian tetrapod footprints from the Spanish Pyrenees.
       Palaeogeography, Palaeoclimatology, Palaeoecology 417, 112–120.
Voigt, S. & Lucas, S. G. 2015. Permian tetrapod ichnodiversity of the Prehistoric Trackways
       National Monument (south-central New Mexico, USA). New Mexico Museum of Natural
       History and Science Bulletin 65, 153–167.
Voigt, S. & Lucas, S. G. 2017. Early Permian tetrapod footprints from central New Mexico. New
       Mexico Museum of Natural History and Science Bulletin 77, 333–352.
White, T. E. 1939. Osteology of Seymouria baylorensis Broili. Bulletin of the Museum of
       Comparative Zoölogy 85(5), 323–409 + 3 pls.
Zouicha, A., Voigt, S., Saber, H., Marchetti, L., Hminna, A., El Attari, A., Ronchi, A. &
       Schneider, J. W. 2021. First record of permian continental trace fossils in the jebilet
       massif,    Morocco.     Journal    of   African    Earth    Sciences    173,    104015.
       https://doi.org/10.1016/j.jafrearsci.2020.104015
Figure 1. A: Geological map of Menorca (modified after Rosell et al. 1989a), indicating the
location of Cala del Pilar. B: Detailed geological map of the study zone, indicating where the log
was measured (toponyms after Buenaventura 2004). C: Synthetic stratigraphic log of Cala del
Pilar–Pla de Mar section, indicating the fossiliferous horizons. Those with a question mark were
found ex situ and attributed to that bed based on lithological equivalence.
Figure 2. Ichnites of the boulder herein named MT01 from an indeterminate Permian of Cala del
Pilar–Pla de Mar section (Menorca), with height models and interpretative drawings. A: Picture
of MT01 as it was found. B: Interpretative drawing of MT01, with each number referring to a
specific ichnite under the nomenclature MT01-[number]. C: Picture, false colour-coded height
model and interpretative drawing of MT01-1 and MT01-2 (Hyloidichnus isp.). D: Picture, false
colour-coded height model and interpretative drawing of MT01-10 (Hyloidichnus isp.). E:
Picture, false colour-coded height model and interpretative drawing of MT01-13 (cf. Erpetopus
isp.).
Figure 3. Holotype specimen of Balearosaurus bombardensis gen. et sp. nov. (IPS35597, right
maxillar and palatine), from an indeterminate Permian of Cala del Pilar–Pla de Mar section
(Menorca). A: labial view, B: anterior view, C: lingual view, D: occlusal view, E: posterior view,
F: dorsal view. it: isolated tooth; mx: maxillar; pl: palatine; tr1–3: teeth row 1–3. All specimens
in the same scale except for D3.
Figure 4. Strict consensus of the best 36 trees recovered (tree length = 251 steps) of the
Captorhinomorpha, including the large moradisaurines of the Balearic Islands, using a branch-
and-bound search. Consistency index (CI) = 0.553, retention index (RI) = 0.756. Double-digit
numbers on the branches represent the bootstrap support values (n = 1000, values under 50 not
shown), and single digits below represent the Bremer decay support value of that node.
Figure 5. Pictures and interpretative drawings of cranial and axial elements of cf. Balearosaurus
bombardensis gen. et sp. nov. from an indeterminate Permian of Cala del Pilar–Pla de Mar section
(Menorca). A–F: IPS35598, distal fragment of left jaw. A: lingual view, B: anterior view, C:
labial view, D: ventral view, E: posterior view, F: occlusal view. G–L: IPS35592, anterior dorsal
vertebra. G: right lateral view, H: anterior view, I: left lateral view, J: posterior view, K: ventral
view, L: dorsal view. M–R: IPS35590, middle caudal vertebra. M: right lateral view, N: anterior
view, O: left lateral view, P: posterior view, Q: ventral view, R: dorsal view. S–T: IPS35588,
possible fragment of haemal arch. S: right lateral view, T: anterior view. azg: prezygapophysis;
cazgp:     centroprezygapophyseal       process;    cfa:      alveolus   of   caniniform;     cpzgp:
centropostzygapophyseal process; cr: cortical rim; de: dentary; di: diapophysis; hk: haemal keel;
iazgf: infraprezygapophyseal fossa; nc: neural canal; ns: neural spine; pa: parapophysis; pd:
pedicel;    pl:   palatine;    psf:    postspinal    fossa;     pzg:     postzygapophysis;     spzgf:
suprapostzygapophyseal fossa.
Figure 6. Pictures and interpretative drawings of girdle and limb elements of cf. Balearosaurus
bombardensis gen. et sp. nov. from an indeterminate Permian of Cala del Pilar–Pla de Mar section
(Menorca). A–F: IPS120163, right ilium. A: lateral view, B: anterior view, C: medial view, D:
posterior view, E: ventral view, F: dorsal view. G–I: IPS120164, left pubis, G: medial view, H:
ventral view, I: lateral view. J–O: IPS120165, fragment of the proximal epiphysis of a left tibia.
J: extensor view, K: lateral view, L: flexor view, M: distal view, N: medial view, O: proximal
view. aasr: area of attachment of sacral ribs; cnc: cnemial crest; ib: iliac blade; in: iliac neck; of:
obturator foramen; tbp: tibial plateau.
Figure 7. Pictures and interpretative drawings of cranial and axial elements of Moradisaurinae
indet. from an indeterminate Permian of Cala del Pilar–Pla de Mar section (Menorca). A–F:
IPS120166, proximal fragment of left jaw. A: lingual view, B: anterior view, C: labial view, D:
ventral view, E: posterior view, F: occlusal view. G–L: IPS35588, middle/posterior dorsal
vertebra. G: right lateral view, H: anterior view, I: left lateral view, J: posterior view, K: ventral
view, L: dorsal view. af: adductor fossa; ag: angular; azg: prezygapophysis; co: coronoid; cp:
coronoid process; cr: cortical rim; de: dentary; di: diapophysis; mc: mandibular canal; mf:
Meckelian foramen; mr: mandibular ramus; nc: neural canal; ns: neural spine; pa: parapophysis;
pd: pedicel; pra: prearticular; pzg: postzygapophysis; sp: splenial; tp: teeth plate; tr1–3: teeth
row 1–3.
Figure 8. Reconstruction of the palaeoassemblage of the Permian P3 unit of Menorca,
representing one specimen of Balearosaurus bombardensis gen. et sp. nov. (background) and two
specimens of the smaller Moradisaurinae indet. (foreground), wandering on a crevasse splay lobe
and leaving their tracks (Hyloidichnus) near other cf. Erpetopus tracks. Created by Henry
Sutherland Sharpe. © 2021 Henry Sutherland Sharpe. Used under license.
Figure 9. World map during the Permian (modified from Scotese 2014) with the localities that
have yielded bones and tracks of possible moradisaurine captorhinid eureptiles. A: Captorhinikos
chozaensis, Captorhinikos parvus, Captorhinikos valensis, Labidosaurikos meachami, a tooth
plate from an indeterminate species and Hyloidichnus isp. from the lower Permian (Gilmore 1927;
Stovall 1950; Olson 1954, 1962b, 1970; Haubold et al. 1995; Lucas et al. 2013; Modesto et al.
2014, 2016; LeBlanc et al. 2015; Voigt & Lucas 2015, 2017; Schneider et al. 2020), and Kahneria
seltina, Rothianiscus multidonta and Rothianiscus robusta from the lower–middle Permian of
southern North America (Olson & Beerbower 1953; Olson 1962a, 1965; Olson & Barghusen
1962). B: Hyloidichnus isp. from the lower Permian (Voigt et al. 2011; Zouicha et al. 2021), and
Acrodenta irerhi, an indeterminate moradisaurine and Hyloidichnus isp. from the middle–upper
Permian of northeastern Africa (Jalil & Dutuit 1996; Hmich et al. 2006; Voigt et al. 2010; Hminna
et al. 2012; Moreau et al. 2020). C: Hyloidichus isp. from the lower Permian of northern Iberian
Peninsula (Gand et al. 1997; López-Gómez et al. 2019b). D: Hyloidichnus isp. from the lower
Permian, and Hyloidichnus isp. and Merifontichnus isp. from the middle Permian of southern
Massif Central and Provence (Heyler & Lessertisseur 1963; Gand 1988, 1993; Gand et al. 2000;
Gand & Durand 2006; Michel et al. 2015; Logghe et al. 2021). E: Hyloidichnus isp. from the
lower Permian (Voigt & Haubold 2015; Mujal et al. 2016) and possible Merifontichnus isp. from
the middle Permian of the Pyrenees (Mujal et al. 2017). F: Merifontichnus isp. from the lower
Permian of Sardinia (Citton et al. 2019; Santi et al. 2020). G: Gecatogomphius kavejevi from the
middle Permian of eastern Europe (Vjushkov & Chudinov 1957; Olson 1962a; Ivakhnenko 2008).
H: Hyloidichnus isp. from the lower Permian of northern Anatolia (Gand et al. 2011). I:
Gansurhinus qingtoushanensis from the middle–upper Permian of central-east Asia (Reisz et al.
2011). J: Hyloidichnus isp. and Merifontichnus isp. from the lower Permian of the Alps
(Marchetti et al. 2013, 2015a, 2015b, 2015c; Marchetti 2016; Santi et al. 2020). K: indeterminate
moradisaurine and Hyloidichus isp. from the lower Permian of Mallorca (Calafat et al. 1986,
1987; Calafat 1988; Gand et al. 2010; Liebrecht et al. 2017; Matamales-Andreu et al. 2019), and
Balearosaurus bombardensis gen. et sp. nov., an indeterminate moradisaurine and Hyloidichnus
isp. from an indeterminate Permian of Menorca (the present work). L: possible Merifontichnus
isp. from the middle–upper Permian of north-central Africa (Contessi et al. 2018). M:
Hyloidichnus isp. and Moradisaurus grandis from the middle–upper? Permian of central Africa
(Ricqlès & Taquet 1982; O’Keefe et al. 2005; Smith et al. 2015; Olroyd & Sidor 2017; Modesto
et al. 2019). N: Hyloidichnus isp. from an indeterminate Permian of southern South America
(Melchor & Sarjeant 2004; Marchetti et al. 2020a). O: Captorhinikos sp. from the lower Permian
of northern South America (Cisneros et al. 2020a).
Table 1. Set of measurements taken on selected footprints of MT01. Although all the ichnites
have been numbered, only the best preserved ones have been measured. Columns without data
correspond to poorly-preserved ichnites that have been used for trackway measurements, such as
MT01-3, or to well-preserved ichnites without trackway information, such as MT01-10 and
MT01-13.

                                                Track parameters
                                   MT01-1       MT01-2     MT01-3        MT01-4
                                                                                     MT01-10           MT01-13
 Footprint number                   (right       (right      (left        (right
                                                                                     (left ?pes)    (right ?manus)
                                     pes)       manus)       pes)          pes)
                                                                                                     cf. Erpetopus
 Identification                                          Hyloidichnus isp.
                                                                                                           isp.
 Length (mm)                         26.4           -             -           -           22.8             10.9
 Width (mm)                            -            -             -           -              -             11.5
 Length sole (mm)                    13.0          9.0            -         13.9           9.5             4.7
 Width sole (mm)                       -          15.0            -         12.6          12.5             5.5
 Length I (mm)                       6.7            -             -           -            7.3             4.3
 Length II (mm)                      10.0           -             -           -            8.8             6.4
 Length III (mm)                     11.4           -             -           -           11.3             7.6
 Length IV (mm)                      15.0         12.8            -           -           15.0             7.8
 Length V (mm)                         -           7.8            -           -              -             2.9
 Divergence angle I–II (º)           15.4           -             -           -           16.7             44.3
 Divergence angle II–III (º)         4.3            -             -           -           27.9             21.6
 Divergence angle III–IV (º)         21.7           -             -           -           18.7               -
 Divergence angle IV–V (º)             -          21.4            -           -              -             95.3
 Divergence angle I–V (º)              -            -             -           -              -            161.5
             Trackway parameters (in brackets, footprints taken into consideration for that measurement)
   Footprint numbers of each            MT01-1, MT01-2, MT01-3, MT01-4                  MT01-10        MT01-13
             trackway               (right manus-pes set, left pes and right pes)      (left ?pes)    (right ?pes)
 Pace angulation pes (º)                            71.9 (1–3–4)                             -               -
 Pace angulation manus (º)                                 -                                 -               -
 Divarication pes midline (º)                           5.0 (1)                              -               -
 Divarication manus midline (º)                        44.6 (2)                              -               -
 Stride pes (mm)                                     78.7 (1–4)                              -               -
 Stride manus (mm)                                         -                                 -               -
 Pace pes (mm)                           67.0 (mean of 1–3: 69.4, 3–4: 64.6)                 -               -
 Pace manus (mm)                                           -                                 -               -
 Length pace pes (mm)                    39.4 (mean of 1–3: 43.3, 3–4: 35.4)                 -               -
 Length pace manus (mm)                                    -                                 -               -
 Width pace pes (mm)                     54.0 (mean of 1–3: 54.0, 3–4: 54.0)                 -               -
 Width pace manus (mm)                                     -                                 -               -
 Interpes distance (mm)                              39.9 (1–3)                              -               -
 Intermanus distance (mm)                                  -                                 -               -
 Manus-pes distance (mm)                             12.9 (1–2)                              -               -
 Width external (mm)                                       -                                 -               -
 Width internal (mm)                                       -                                 -               -
 Glenoacetabular distance
                                                           -                                 -               -
 (mm)