This is the accepted version of the article: Matamales Andreu, Rafel; Mujal, Eudald; Dinarès Turell, Jaume; [et al.]. «Early- middle Permian ecosystems of equatorial Pangaea : Integrated multi-stratigraphic and palaeontological review of the Permian of Mallorca (Balearic Islands, western Mediterranean)». Earth-Science Reviews, (January 2022), art. 103948. DOI 10.1016/j.earscirev.2022.103948 This version is available at https://ddd.uab.cat/record/251863 under the terms of the license 1 Early–middle Permian ecosystems of equatorial Pangaea: integrated multi- 2 stratigraphic and palaeontological review of the Permian of Mallorca (Balearic 3 Islands, western Mediterranean) 4 5 Rafel Matamales-Andreua,b*, Eudald Mujala,c, Jaume Dinarès-Turelld, Evelyn Kustatschere,f, 6 Guido Roghig, Oriol Omsh, Àngel Galobarta,i & Josep Fortunya 7 a 8 Institut Català de Paleontologia Miquel Crusafont, Universitat Autònoma de Barcelona, Edifici 9 ICTA-ICP, c/ Columnes s/n, Campus de la UAB, 08193 Cerdanyola del Vallès, Barcelona, Spain. 10 b 11 Museu Balear de Ciències Naturals, carretera Palma–Port de Sóller Km. 30, 07100 Sóller, 12 Mallorca, Spain. 13 c 14 Staatliches Museum für Naturkunde Stuttgart, Rosenstein 1, 70191 Stuttgart, Germany. 15 d 16 Istituto Nazionale di Geofisica e Vulcanologia, Via di Vigna Murata 605, 00143 Roma, Italy. 17 e 18 Department für Geo- und Umweltwissenschaften, Paläontologie und Geobiologie, Ludwig- 19 Maximilians-Universität, Richard-Wagner-Straße 10, 80333 München, Germany. 20 f 21 Bayerische Staatssammlung für Paläontologie und Geobiologie, Richard-Wagner-Straße 10, 22 80333 München, Germany. 23 g 24 Istituto di Geoscienze e Georisorse - CNR, Via Gradenigo 6, 35131 Padova, Italy. 25 26 h Departament de Geologia, Universitat Autònoma de Barcelona, av. de l’eix Central s/n, Campus 27 de la UAB, 08193 Cerdanyola del Vallès, Barcelona, Spain. 28 i 29 Museu de la Conca Dellà, c/ del Museu 4, 25650 Isona i Conca Dellà, Lleida, Spain. 30 31 *Corresponding author: rafel.matamales@icp.cat 32 33 34 35 36 1 1 Abstract 2 The Cisuralian–Guadalupian (early–middle Permian) was a period of climate transition between 3 the Carboniferous icehouse conditions to the latest Permian–Early Triassic hothouse. The 4 landmasses had coalesced in the supercontinent Pangaea and the climate was progressively 5 becoming more arid, especially in a belt over the palaeoequator. The deposits of present-day 6 Mallorca (Balearic Islands, western Mediterranean) were located in those low palaeolatitudes, in 7 the western margin of the Tethys Sea, and correspond to alluvial systems with meandering rivers. 8 The present study divides the stratigraphic succession into three main units, formally described 9 herein as the Bec de s’Àguila Formation, Port des Canonge Formation and Pedra de s’Ase 10 Formation. Based on an exhaustive review of the literature and new magneto- and biostratigraphic 11 data, the sequence has been dated between the early and middle Permian (Artinskian–Wordian). 12 Moreover, the detailed study of the fossils has provided a complete account of the denizens of 13 those ecosystems. Tetrapod tracks occur abundantly in the Port des Canonge Formation, with 14 morphotypes attributed to moradisaurine captorhinid eureptiles, araeoscelidian diapsids/non- 15 varanodontine varanopids, possible pareiasauromorph parareptiles, “pelycosaur”-grade synapsids 16 and indeterminate synapsids. Spores and pollen grains from the Pedra de s’Ase Formation indicate 17 an overall dominance of conifers, accompanied by sphenophytes, ferns and seed ferns. Overall, 18 apart from providing the first detailed interpretation of the ecosystems of the Permian of Mallorca, 19 these new data have made it possible to improve the characterisation of the Permian–Triassic 20 tectonosedimentary cycle in the Balearic Islands, which contribute to the understanding of the 21 evolution of the western peri-Tethys ecosystems. 22 23 Key-words: Cisuralian, Guadalupian, magnetostratigraphy, palynology, tetrapod tracks, central 24 Pangaea 25 26 27 28 1. Introduction 29 The Permian was a period of great climatic, environmental and biotic changes. The assembly of 30 the supercontinent Pangaea during the Pennsylvanian (late Carboniferous) and throughout the 31 Permian, together with the uplift of the Variscan mountains in the equatorial region, resulted in a 32 profound alteration of the climates of the planet (e.g., Tabor & Poulsen, 2008; Stampfli et al., 33 2013). There was a sustained aridification trend, from the Carboniferous icehouse conditions to 34 the Triassic hothouse (Montañez et al., 2007; Sun et al., 2012; Montañez & Poulsen, 2013; 35 MacLeod et al., 2017), which contributed to the settling of a megamonsoonal regime that affected 36 the low latitudes of Pangaea, alternating arid seasons with episodes of heavy rainfalls (e.g., 2 1 Parrish, 1993). As a result, the ecosystems underwent extensive remodelling, which translated 2 into several important events of biological turnover. The Cisuralian continental tetrapod faunas 3 were reminiscent of those of the Carboniferous, with an abundance of amphibians and 4 “pelycosaur”-grade synapsids (Ruta & Benton, 2008; Brocklehurst et al., 2013). However, a 5 remarkable faunal turnover occurred by the Guadalupian when, in the aftermath of the so-called 6 Olson’s Extinction (Brocklehurst et al., 2017; Olroyd & Sidor, 2017; Brocklehurst, 2020; but see 7 Lucas, 2017), several groups of parareptiles and therapsids first appeared and readily 8 outnumbered the residual representatives of the once-dominant amphibian groups (Sahney & 9 Benton, 2008; Benson & Upchurch, 2013). Another extinction event struck the tetrapod faunas 10 just before the Lopingian (Retallack et al., 2006; Lucas, 2009; Day et al., 2015), which was 11 dominated by a diverse array of derived therapsid groups (Bernardi et al., 2017; Lucas, 2017). 12 The Permian period ended with the most dramatic extinction event in the Phanerozoic, which 13 wiped out almost all life on earth (Erwin, 1994; Benton & Twitchett, 2003; Benton, 2008), leaving 14 empty ecological niches for the succeeding Mesozoic communities to fill (Romano et al., 2020). 15 During the Permian, sedimentation in the western margins of the Tethys sea (including the 16 present-day Balearic Islands, western Mediterranean) took place in many small, relatively isolated 17 basins (e.g., McCann et al., 2006), making lithostratigraphic comparison among basins, even 18 close ones, difficult. Asselian–Sakmarian (‘Autunian’) deposits of the Iberian Peninsula, Massif 19 Central, Provençe and Sardigna usually correspond to a continuation of the organic matter-rich 20 facies of the underlying Carboniferous deposits, representing sedimentation of lakes and 21 floodplains under humid conditions (Sopeña et al., 1977; Cassinis & Ronchi, 2002; Cassinis et 22 al., 2003; Schneider et al., 2006; Durand, 2008; Lopez et al., 2008; Michel et al., 2015; Mujal et 23 al., 2018; López-Gómez et al., 2019a, 2019b, 2021). Sakmarian–Kungurian (‘Saxonian’) deposits 24 also appear in most of the basins mentioned above and in the Alps (Cassinis et al., 2012). They 25 represent semi-arid settings, with playa lake and fluvial channel deposits, sometimes with 26 lacustrine deposits near the top of the sequences (see references cited above). In the cases when 27 both groups are present, they are usually, but not always, bound by an unconfomity corresponding 28 to a sedimentary hiatus. Roadian–Wuchiapingian (‘Thuringian’) deposits are usually thicker and 29 more widespread, and appear in Menorca, Iberian Peninsula, Massif Central, Provençe and 30 Sardigna, representing semi-arid floodplains traversed by braided or meandering river systems 31 (Cassinis et al., 2003; Gand & Durand, 2006; Schneider et al., 2006; Durand, 2008; Bercovici et 32 al., 2009; Linol et al., 2009; De la Horra et al., 2012; Michel et al., 2015; Mujal et al., 2017a). In 33 the Alps, the ‘Thuringian’ sequences, as defined originally, span from the Wuchiapingian to the 34 Changshingian, and exhibit a marine influence towards the East (Cassinis et al., 2012; Bernardi 35 et al., 2017). In most of the aforementioned sections, the sedimentary palaeoenvironments and 36 even some palaeoclimatic signals seem to reflect local conditions (with a superimposed global 3 1 aridification trend), which further complicates correlations. The majority of those units have 2 absolute age attributions from volcanic rocks, which are altogether absent in the sequences of 3 Mallorca studied here, and therefore the datings of the latter rely on constraints imposed by 4 palaeomagnetism and fossils (magneto- and biostratigraphy). 5 The present work exhaustively reviews and integrates all the previous stratigraphic and 6 palaeontological data on the Permian of Mallorca (Balearic Islands, western Mediterranean) with 7 new pieces of evidence, including palaeomagnetic, palynological, palaeobotanical and 8 ichnological data. The lithostratigraphic framework is revised, providing new stratigraphic 9 sections, clearing previous misconceptions and describing three formal units with rank of 10 formation. The palaeodepositional environments and their evolution through time are interpreted 11 from the sedimentological study, and biotic communities are described by study of spores, pollen 12 and macroplant remains, together with trace fossils produced by both invertebrates and 13 vertebrates. These fossil remains provide relatively precise age attributions for the two upper 14 formations, and the performed magnetostratigraphic analysis further constrains these datings. 15 Finally, these data are considered in the context of equatorial Pangaea in order to identify patterns 16 regarding climate and biogeography. 17 18 19 2. Geographical and geological context 20 The Balearic Islands are an archipelago located in the western Mediterranean (Figure 1A), as a 21 northeastern extension of the Betic fold and thrust belt, uplifted during the Alpine orogeny (Vera 22 et al., 2004). Rocks of Permian age crop out only on the two largest islands, Mallorca and 23 Menorca (Pomar-Gomà, 1979; Obrador, 1983; Rodríguez-Perea et al., 1987; Calafat, 1988; 24 Rosell et al., 1988; Gómez-Gras, 1993), but their successions were probably deposited in separate 25 basins along the eastern margin of the Iberian plate (Gómez-Gras, 1993; López-Gómez et al., 26 2019a). In fact, the upper Palaeozoic–lower Mesozoic basins of the Balearic Islands form part of 27 the same structural system as the basins from the Iberian Peninsula, as a whole known as the 28 Iberian area. The Permian basins of the Balearic Islands, similarly to those of the rest of the Iberian 29 Peninsula, were opened during the latest Carboniferous–earliest Permian, when the Variscan 30 orogen started to collapse (McCann et al., 2006; López-Gómez et al., 2019a). This resulted in a 31 dominant transtensional and extensional tectonic regime acting on the region, which favoured the 32 development of semi-grabens where the sediments accumulated (López-Gómez et al., 2019a). 33 Those basins were palaeogeographically located in the western peri-Tethys (see Roscher & 34 Schneider, 2006), drifting from a latitude of about 7 ºS in the earliest Permian to about 4 ºN during 35 the latest Permian (Scotese, 2014a, 2014b). The climate is thought to have been tropical 4 1 throughout (Roscher et al., 2008), under semi-arid, seasonal conditions (Gómez-Gras & Alonso- 2 Zarza, 2003; Bercovici et al., 2009). 3 On Mallorca, rocks of Permian age intermittently crop out along the coastal cliffs of the 4 northwestern side of the Serra de Tramuntana, between Racó de s’Algar (Banyalbufar) and Platja 5 de sa font Figuera (Valldemossa) (Figure 1). They extend inland only in the valley behind Port 6 des Canonge, but there they are mostly covered by forests. The base of the Permian group of units 7 remains unknown, as the boundary with the underlying Carboniferous Culm facies is on a 8 geological fault (Rodríguez-Perea & Ramos, 1984; Ramos & Rodríguez-Perea, 1985; Calafat, 9 1988). The boundary with the overlying Lower Triassic Buntsandstein facies has tentatively been 10 recognised as an unconformity in the Pedrera de sa Cova section for the first time in the present 11 study. Previous authors divided the Permian series into two (Ramos et al., 1985; Ramos, 1995), 12 three (Calafat, 1988) or four (Gómez-Gras, 1993) informal lithostratigraphic units (see 13 Supplementary Text 1; Supplementary Table 1; Matamales-Andreu et al., 2021a), which were 14 never properly collated. The present work provides a detailed study of all the relevant sections of 15 the island (Figure 1B–D) and formal definitions for each of the lithostratigraphic units to avoid 16 ambiguity in future studies. 17 18 19 3. Material and methods 20 3.1. Stratigraphy and sedimentology 21 For the stratigraphic and sedimentological study, 12 stratigraphic sections have been logged at 22 1:25 scale (here presented in 1:40 scale in Supplementary Logs) by means of a Jacob’s staff and 23 a measuring tape, down to minimum resolution of 1 cm of bed thickness. Texture, thickness, 24 sedimentary structures, colour, palaeontological content and lithofacies (Table 1) have been also 25 considered. Part of some of the logs corresponds to flooded or vertical passes, which have been 26 logged either from within the water or using climbing gear, respectively. The logs are named, 27 from South-West to North-East (Figure 1): ‘Racó de s’Algar’ (RA, 149.3 m), ‘Torrent de na 28 Nadala’ (NA, 192.5 m), ‘Es Tamarell’ (TA, 27.8 m), ‘Punta d’en Pere Mir’ (PM, 30.0 m), ‘Pedra 29 de s’Ase’ (PA, 167.3 m), ‘Pedra de s’Ase - Summit’ (PS, 11.0 m), ‘Volta des General’ (VG, 5.9 30 m), ‘Platja de sa Pedrera’ (PP, 13.3 m), ‘Port des Canonge–Hort de sa Cova’ (PC, 604.4 m), 31 ‘Pedrera de sa Cova’ (CO, 190.0 m), ‘Sa Gratallosa’ (GR, 8.6 m) and ‘Marina de Valldemossa’ 32 (MV, 70.0 m). These logs have been synthesised (1:1160 scale) and correlated for each of the 33 four main areas, in order to overcome the local distortion produced by faulting: ‘Racó de s’Algar– 5 1 Pedra de s’Ase section’, ‘Port des Canonge–Sa Gratallosa section’, ‘Pedrera de sa Cova section’ 2 and ‘Marina de Valldemossa section’ (see Supplementary Correlations). Finally, the synthetic 3 logs of each of those sections have been correlated (see ‘4. Stratigraphy and sedimentology’ 4 below). The datum to correlate the two main synthetic sections, ‘Racó de s’Algar–Pedra de s’Ase 5 section’ and ‘Port des Canonge–Sa Gratallosa section’, is the boundary between the Port des 6 Canonge Formation and the Pedra de s’Ase Formation, that is, the change from dominant red 7 lutites and fine-grained sandstones to pink/white/blue medium-grained sandstones (Figure 2). The 8 position of the ‘Marina de Valldemossa section’ within the Pedra de s’Ase Formation can only 9 be tentatively assigned to its middle part based on the similarity of the sequences (Figure 3). The 10 boundary between Permian and Triassic units seems to be present at the ‘Pedrera de sa Cova 11 section’ and thus it has been broadly assigned to the upper part of the Pedra de s’Ase Formation 12 (Figure 3). The sedimentary lithofacies and architectural elements were classified according to 13 the nomenclature of Miall (1977, 1985, 2006) and Postma (1990), with modifications introduced 14 by Linol et al. (2009) for the Permian sequence of the neighbouring island of Menorca (Table 1). 15 The architectural elements have been classified according to Miall (1985, 2006) (Table 2). 16 17 3.2. Magnetostratigraphy 18 In order to characterise the geomagnetic polarity of rocks along the studied successions and erect 19 a magnetostratigraphy, 234 oriented hand samples were taken from their corresponding 20 stratigraphic levels, spanning about 835 m of strata. Sampling was focused on lithologies that 21 were potentially most suitable for palaeomagnetism (i.e., the red-coloured, finest-grained 22 lithologies). A regular spacing between samples was usually maintained, although this was not 23 possible in the intervals of medium-/coarse-grained sandstones and those that were not cropping 24 out. Collected samples are distributed along several stratigraphic sections named, from southwest 25 to northeast (Figure 1): ‘Racó de s’Algar’ (RA1–RA4 sampling levels), ‘Torrent de na Nadala’ 26 (NA1–NA46), ‘Volta des General’ (VG1–VG5), ‘Platja de sa Pedrera’ (PP1–PP3), ‘Port des 27 Canonge–Hort de sa Cova’ (PC1–PC152), ‘Pedrera de sa Cova’ (CO1–CO24) (see 28 Supplementary Logs for the precise location of all the collected samples). Disregarding major 29 non-outcropped intervals, the overall sampling resolution is 2–4 m. The aforementioned sections 30 have been correlated and integrated into three main synthesised stratigraphic logs, ‘Racó de 31 s’Algar–Pedra de s’Ase section’, ‘Port des Canonge–Hort de sa Cova section’ and ‘Pedrera de sa 32 Cova section’ (see section ‘3.1. Stratigraphy and sedimentology’ for details). Strata dip along 33 those three sections is similar and moderate (strike/dip angles at about 090/30, 085/28, and 066/26 34 respectively, see Supplementary Table 2). The similar bedding attitude of the studied sections 35 prevents a meaningful palaeomagnetic fold test. 6 1 Collected samples were subsequently cut in standard palaeomagnetic regular specimens for 2 laboratory analysis. A total of 144 samples were fully demagnetised for the present study (about 3 62% of the collected samples, see Supplementary Table 2). Natural remanent magnetisation 4 (NRM) and remanence through demagnetisation were measured on a 2G Enterprises DC SQUID 5 high-resolution pass-through cryogenic magnetometer (manufacturer noise level of 10 -12 Am2) 6 operated in a shielded room at the Istituto Nazionale di Geofisica e Vulcanologia in Rome, Italy. 7 A Pyrox oven in the shielded room was used for thermal demagnetisations and alternating field 8 (AF) demagnetisation was performed with three orthogonal coils installed inline with the 9 cryogenic magnetometer. Progressive stepwise AF demagnetisation was routinely used and 10 applied after a single heating step to 150 °C. AF demagnetisation included usually 14 steps (4, 8, 11 13, 17, 21, 25, 30, 35, 40, 45, 50, 60, 80, 100 mT). Subsequently, thermal demagnetisation 12 resumed through variable temperature increments (20–100 °C) up to 690 °C. In the context of the 13 studied redbeds, applying a first heating step followed by AF demagnetisation prior to full thermal 14 demagnetisation makes it possible to both unblock eventual magnetisation carried by goethite 15 (usually unblocking below 120 °C ) and also magnetite-like low coercivity ferromagnetic phases. 16 Consequently, magnetic phases even unblocking at relatively low temperatures during the final 17 thermal protocol must be assigned to high coercivity phases (i.e., hematite). Characteristic 18 remanent magnetisations (ChRM) were calculated by Principal Component Analysis (Kirschvink, 19 1980) and by the great circle technique (MacFadden & McElhinny, 1988) from orthogonal vector 20 endpoint demagnetisation diagrams (Zijderveld, 2013) using the online open-source software 21 Paleomagnetism.org (Koymans et al., 2016, 2020). The magnetic stratigraphy is based on virtual 22 geomagnetic pole (VGP) latitudes. 23 In order to characterise ferromagnetic mineralogy, some rockmagnetic experiments were 24 performed in selected samples. Thermomagnetic heating and cooling cycles where measured with 25 an AGICO MFK1 susceptibility bridge with a CS3 furnace attachment with nominal sensitivity 26 (5 × 10–7 SI) and open air into the tube. Hysteresis loops, isothermal remanent magnetization 27 (IRM) acquisition and back-field IRM were measured at room temperature with a Princeton 28 Measurements Corp. Model 3900 MicroMagTM Vibrating Sample Magnetometer (VSM) (noise 29 level 5 × 10−9 Am2). IRM curve unmixing was performed with IRM MaxUnmix package 30 (Maxbauer et al., 2016). 31 32 3.3. Palaeopalynology and palaeobotany 33 For the present study, 35 rock samples were collected from the studied stratigraphic sections in 34 order to search fossil sporomorphs and palynomorphs (Supplementary Table 4). The beds chosen 7 1 to be sampled were generally greyish-bluish lutites or very fine-grained sandstones. Specifically, 2 there are three samples in the Port des Canonge Formation of log RA; one sample in the Port des 3 Canonge Formation and three samples in the Pedra de s’Ase Formation of NA; thirteen samples 4 in the Pedra de s’Ase Formation of log PA; two samples in the Pedra de s’Ase Formation of log 5 PS; one sample in the Port des Canonge Formation and three samples in the Pedra de s’Ase 6 Formation of log PC; four samples in the Pedra de s’Ase Formation and one sample in the Punta 7 Roja Formation(?) of log CO; and three samples in the Pedra de s’Ase Formation of log MV (see 8 exact position of all the samples in Supplementary Logs). 9 To extract the sporomorphs and palynomorphs, rock samples were crushed and treated with HCl 10 (37%) and HF (47%) to dissolve the non-organic material. After washing and sieving (15 μm 11 nylon mesh), the residue was stored in water and then strew mounted onto microscope slides using 12 Entellan glue as the mounting medium. The microscope slides were studied under a Leica DM750 13 light microscope, and the index species were photographed using a Leica ICC50 W digital 14 camera. Slides are permanently housed in the Museu de Mallorca (Palma, Mallorca, Balearic 15 Islands, Spain; see ‘3.5. Institutional abbreviations’ below). 16 Among the different observed macroplant remains, some were not collected because of their very 17 large size (i.e., tree logs) or being included in very large and hard rock surfaces. Those were 18 identified according to the following code: [stratigraphic log label]-[level]-[correlative number 19 for each macroplant remain in that level]. Macroplant remains that were collected are permanently 20 housed in the Museu de Mallorca (Palma, Mallorca, Balearic Islands, Spain; see ‘3.5. Institutional 21 abbreviations’ below). 22 23 3.4. Tetrapod ichnites 24 Digital 3D models of the surfaces with ichnites were made following the procedure explained by 25 Mujal et al. (2020). Agisoft Photoscan standard v.1.1.4. (http://www.agisoft.com) was used to 26 align the photographs and to create the dense point clouds, meshes and textures. MeshLab 27 v.2016.12 (http://meshlab.sourceforge.net/) was used to scale, orient and crop the models. The 28 false colour-coded height maps with contours were built using ParaView v.5.5.0-RC4 64-bit 29 (http://www.paraview.org). ImageJ v.1.52d (https://imagej.nih.gov/ij/) was used to measure, 30 whenever possible, the standard parameters of the ichnites recommended by Leonardi (1987) and 31 Hasiotis et al. (2007). All measurements of the ichnites studied herein are listed in Supplementary 32 Table 5. 8 1 The specific nature of the ichnological material, where one ‘specimen’ (=rock slab with 2 footprints) may have several unrelated tracks, or some footprints forming a trackway, calls for a 3 particular set of rules to accurately reference each ichnite. In the present work, the slabs are 4 identified according to following code: [stratigraphic log label]-[level, “exs” if found ex situ]- 5 [correlative number for each slab in that level]-[correlative number indicating the 6 trackway][correlative letter indicating the ichnite] (see Supplementary Table 5). All the ichnites 7 considered herein (both left in the field and collected) were consistently numbered using that 8 code. Correspondence of that nomenclature with institutional catalogue numbers of the slabs that 9 were collected from the field are in Supplementary Table 5. Slabs with ichnites that were collected 10 are permanently housed in the Museu de Mallorca (Palma, Mallorca, Balearic Islands, Spain; see 11 ‘3.5. Institutional abbreviations’ below). 12 The tetrapod tracks studied herein show different states of preservation, depending on the layer 13 and on the size of the ichnites. More than half of the ichnites have a type 3 preservation value 14 (optimal) according to the scale of Marchetti et al. (2019a), and the rest are of types 2 (good), 1 15 (intermediate) and, very rarely, 0 (poor). To count the relative proportions of each ichnotaxon 16 (see ‘8.1. Age attributions’ below), the methodology of Marchetti et al. (2017a) was not used 17 because most of the surfaces with ichnites were large (often 0.5–2 m2) and profusely trampled. In 18 this specific case, the “track/slab” method (Marchetti et al., 2017a) would severely underestimate 19 the ichnotaxa with two or more trackways on the same surface, and their “weighting size” method 20 (Marchetti et al., 2017a) would overestimate ichnotaxa with trackways (i.e., Hyloidichnus, 21 Dimetropus) over those that appear as isolated ichnites (i.e., Dromopus). Therefore, in the present 22 work each trackway, regardless of the number of ichnites imprinted, was counted as a single 23 occurrence for that ichnotaxon in that layer. Isolated ichnites (or isolated manus-pes sets) that 24 were not part of a trackway were also counted as a single occurrence. All ichnites have been 25 revised and studied except for one morphotype, attributable to a synapsid trackmaker, which 26 appears to be different from other coeval ichnogenera and is the object of a separate study. 27 Regardless, it has been included in the counts of ‘8.1.3. Tetrapod track biostratigraphy’ as 28 “indeterminate synapsid tracks”. 29 30 3.5. Institutional abbreviations 31 D/21: Museu de Mallorca, Palma, Mallorca, Balearic Islands, Spain. 32 MBCN: Museu Balear de Ciències Naturals, Sóller, Mallorca, Balearic Islands, Spain. 33 UIB: Universitat de les Illes Balears, Palma, Mallorca, Balearic Islands, Spain. 9 1 2 3 4. Stratigraphy and sedimentology 4 Formal lithostratigraphic units have hitherto never been defined for the Permian red-beds of 5 Mallorca. Previous authors (Cuevas-López, 1958a, 1958b; Pomar-Gomà, 1979; Martí et al., 1985; 6 Ramos et al., 1985; Calafat, 1986, 1987, 1988; Rodríguez-Perea et al., 1987; Barnolas, 1991a, 7 1991b; Gómez-Gras, 1992, 1993; Ramos, 1995) divided the Permian–Triassic continental 8 sequence into several informal lithostratigraphic units (see Supplementary Text 1 and 9 Supplementary Table 1). Subsequent reviews (Arche et al., 2002; López-Gómez et al., 2002, 10 2019a; Vera et al., 2004; Bourquin et al., 2007, 2011; Cassinis et al., 2012) upgraded some of 11 those to the rank of formation, without proper description or characterisation. An additional 12 complication is that most of the recent work is based on the stratigraphic framework proposed by 13 Ramos et al. (1985) and Ramos (1995), which incorrectly correlated Permian and Triassic units 14 from different outcrops (see Supplementary Text 1; Matamales-Andreu et al., 2021b). This 15 section provides formal descriptions of all the Permian units of Mallorca, preserving the first 16 name used for each of them. Descriptions and interpretations of all the lithofacies and architectural 17 elements are here presented in Table 1 and Table 2. 18 19 4.1. Bec de s’Àguila Formation 20 This formation (Figure 2) is identified by the presence of conglomerates with clasts of quartz or 21 rocks from the Devonian/Carboniferous basement (in the other formations, the clasts are always 22 soft pebbles and carbonate nodules). The clasts can also appear as isolated grains in the sandstone 23 beds. Moreover, the red sandstone deposits are usually medium- or coarse-grained, in contrast to 24 the overlying formations, in which red sandstones are very fine- or fine-grained. Beds of lutites 25 are rare in this formation. 26 4.1.1. Location and boundaries 27 The only three outcrops of the Bec de s’Àguila Formation are small, mostly covered and heavily 28 affected by tectonics. There are limited exposures at Volta des General and at Sa Gratallosa, and 29 the tickest section has been measured at Platja de sa Pedrera (Supplementary Logs). With 13.3 m 30 of thickness, the section of Platja de sa Pedrera is hereby formally designed as the stratotype of 31 this formation (Figures 1D, 2; Supplementary Logs). Its lower boundary is always determined by 32 faults, with Carboniferous Culm facies in the case of Sa Gratallosa (Rodríguez-Perea & Ramos, 33 1984; Ramos & Rodríguez-Perea, 1985) (Figure 2A) and Platja de sa Pedrera (Calafat, 1988) 10 1 (Figure 2B), and with the Port des Canonge Formation (by means of an inverse fault) in the case 2 of Volta des General. Its upper boundary is a geological fault causing it to contact the Port des 3 Canonge Formation in the case of the sections of Sa Gratallosa (Figure 2A) and Volta des General. 4 At Platja de sa Pedrera, this contact is covered (Figure 2B). 5 4.1.2. Lithological features and palaeontological content 6 The lithofacies (Figure 4, Table 1) and architectural elements (Table 2) present in this formation 7 show a very particular arrangement, with abundance of conglomerate, that makes it possible to 8 distinguish it from all other Permian formations of Mallorca. The conglomerate beds (lithofacies 9 type GmP, Figure 4B) are especially frequent in the lower part, and comprise a red or yellow 10 matrix of medium- to very coarse-grained sandstones and clasts (of variable size) of quartz and 11 lithic fragments of Carboniferous (or older) rocks, that are sub-rounded to very angular. No clear 12 lamination can be seen in those beds, which are mostly horizontal with irregular tops and slightly 13 erosive bases. The clasts are never imbricated and are usually unsorted, although some beds do 14 present either positive or negative grain sorting. Traces of large roots similar to those described 15 in the Permian P1 unit of Menorca (Gómez-Gras & Alonso-Zarza, 2003) can sometimes be 16 observed. Medium to coarse-grained red sandstone beds are also frequent, and are mostly massive 17 (lithofacies type Sm) or show crude trough cross-bedding (lithofacies type St). Sandstone deposits 18 with basal scours (lithofacies type Ss), beds with planar cross-bedding (lithofacies type Sp), 19 horizons with abundant rhizocretions (lithofacies type Sb) and even palaeosols (Calcisols, vertic 20 Calcisols or Vertisols; lithofacies type P) may also appear. Finally, red lutite beds are very rare, 21 being either massive (lithofacies type Fm) or affected by root bioturbation (lithofacies type Fr). 22 The dominant architectural elements in this formation are GB/SG. Secondarily, element LA 23 appears in the upper part of the unit, with rare intercalations of element FF. The only fossils found 24 so far in Bec de s’Àguila Formation are rhizocretions of diverse sizes. 25 4.1.3. Interpretation 26 In this formation, lithofacies type GmP represents the deposits of gravity and debris flows in a 27 colluvial/alluvial-fan environment. Lithofacies type Sm also corresponds to deposition by dense 28 flows. Other sandstone lithofacies, such as those of types St and Sp, have been interpreted to be 29 deposited by fluvial currents during intervals of relatively lower flow regime, whereas type Ss 30 corresponds to higher energy events with erosive capacity. Lithofacies of types Sb and P represent 31 the alteration of other lithofacies types by biogenic activity. The presence of calcic Vertisols, 32 vertic Calcisols and Calcisols point to a semi-arid climate with variations of the water table, 33 possibly due to seasonality (Mack et al., 1993; Alonso-Zarza, 2003; Tabor & Poulsen, 2008). 34 Lutite lithofacies of types Fm and Fr correspond to the fine sediments deposited in the floodplain, 11 1 which can be bioturbated by plant roots. The architectural elements GB/SG record gravity flows 2 in a colluvial/alluvial fan setting, the element LA corresponds to point bars of meandering 3 channels, rarely interbedded with element FF, the floodplain fine deposits. 4 This formation represents colluvial and alluvial-fan debris-flow deposits and the transition 5 towards the fine-grained meandering rivers of the Port des Canonge Formation (see ‘4.2. Port des 6 Canonge Formation’ below). Similar to the P1 unit of Menorca (Gómez-Gras & Alonso-Zarza, 7 2003; Matamales-Andreu et al., 2021c), the debris-flow conglomerates contain mostly 8 extraformational clasts and may develop palaeosols (Calcisols) with large rhizocretions. The 9 medium to coarse-grained sandstones that appear towards the upper part of the formation are 10 usually massive and somewhat tabular but in some cases, such as at the Platja de sa Pedrera 11 section, they present clear lateral accretion (Figure 2), thus representing medium- to coarse- 12 grained sinuous channels with almost no floodplain deposits. The few palaeocurrents measured 13 in this formation (n = 2) point to a possible South–East direction (mean of 137.5º; see ‘8. 14 Discussion’ below). 15 16 4.2. Port des Canonge Formation 17 This formation (Figure 2) can be identified in the field because of the great abundance of very 18 fine-grained rocks compared to the other two Permian formations of Mallorca. Specifically, the 19 typical sequence consists of intervals of very fine- to fine-grained red sandstones of about 2–4 20 metres-thick, with lateral accretion surfaces, overlain by about 2–5 metres of red lutites and very 21 fine-grained red sandstones forming tabular beds. 22 4.2.1. Location and boundaries 23 The Port des Canonge Formation crops out extensively at the Racó de s’Algar–Pedra de s’Ase 24 section (about 222.5 m thick, including covered intervals, Figures 1B, 2C, 2D) and at the Port des 25 Canonge–Hort de sa Cova section (about 368.8 m thick, including covered intervals, Figure 1D). 26 Smaller exposures also occur in the surroundings of Sa Gratallosa (Figures 1D, 2A) and possibly 27 at Nedador de ses Dones (Figure 1C). The thickest and most easily accessible section is that of 28 Port des Canonge–Hort de sa Cova, which is here formally designed as the stratotype for this 29 formation (Figure 2; Supplementary Logs). Its lower boundary is faulted in all cases, whereas its 30 transitional upper boundary with the Pedra de s’Ase Formation is visible in both of the logged 31 sections and is defined by a shift from very fine- to fine-grained red sandstone beds to medium- 32 to coarse-grained pink/blue/white beds with blue lutites at their base (Figures 3A, 3C; 33 Supplementary Logs; Supplementary Correlations). There are large covered stretches in all the 12 1 outcrops representing the lower half of this formation, probably concealing faults; for this reason, 2 the thicknessof this unit has been given in ranges. The minimum corresponds to the thickness of 3 the part of the sequence that is certainly continuous and not faulted, whereas the maximum 4 includes all the covered parts and faulted zones. 5 4.2.2. Lithological features and palaeontological content 6 The lithofacies (Figure 4, Table 1) and architectural elements (Table 2) of this formation show a 7 notable diversity accounting for different depositional palaeoenvironments. Breccia lithofacies of 8 types Gm and Gt (Figure 4A) constitute the base of sandstone packages or as isolated beds among 9 lutites, may be massive or have crude bedding, and their clasts are always soft pebbles of lutite 10 and sandstone, sometimes with carbonate nodules and fragments of rhizocretions. Sandstones 11 account for about the 60% of all the rocks of the studied sections, and the most abundant 12 lithofacies are those of types St and Sl (Figure 4E). In some cases, lithofacies of types Sp, Sm and, 13 rarely, Sh also appear. Lithofacies of types Sr and Sl become abundant towards the upper part of 14 the sandstone intervals, and occur in tabular beds intercalated between lutites. Lithofacies type Ss 15 (Figure 4I) appears rarely, in the form of sandstone beds with erosive bases, with crude bedding 16 and usually soft pebbles. Lithofacies type Sb (Figure 4C) corresponds to sandstones with abundant 17 invertebrate bioturbation. Regarding lutite lithofacies, the most abundant type is certainly Fm, 18 massive, followed by type Fl, with horizontal or ripple lamination. Lithofacies of types Fr and 19 Fb (Figure 4N) show bioturbation produced by plant roots and invertebrate burrows, respectively. 20 Lithofacies type P (Figure 4O), in the form of calcic Vertisols, vertic Calcisols and Calcisols, 21 shows rhizocretions, carbonate nodules of about 1–3 cm of diameter (rarely, calcrete hardpans 22 are present in the lower part of the unit) and/or gleyed patches. In terms of architectural elements, 23 this formation is clearly dominated by the elements LA, with lateral accretion surfaces, 24 LV+CR+CS, sandstones and lutites with tabular or locally erosive geometries, and FF, fine 25 sediments. The element SS is also present very rarely. It is also interesting to note that at the type 26 section (Port des Canonge–Hort de sa Cova), the element LA is overall more frequent than 27 LV+CR+CS and FF, whereas at the Racó de s’Algar–Pedra de s’Ase section the three elements 28 appear in a more balanced proportion. The Port des Canonge Formation is locally very rich in 29 fossils, which include rhizocretions, macrofloral remains, invertebrate trace fossils, tetrapod 30 tracks and tetrapod bones (including complete skeletons). 31 4.2.3. Interpretation 32 In this formation, breccia lithofacies of types Gm and Gt constitute the basal lag of lateral 33 accretion bars and major channel deposits, or as isolated events interbedded between floodplain 34 lutites. They can be interpreted as the reworking of the underlying sediments (usually floodplain 13 1 lutites, sandstones or palaeosols) by meandering channels or unconfined flows of crevasse splays, 2 respectively, exactly as in the Permian of Menorca as described in great detail by Gómez-Gras & 3 Alonso-Zarza (2003). Sandstone lithofacies of types St and Sl, often Sp and Sm and, rarely, Sh, 4 are the main constituents of the lateral accretion bars of major channels. Towards the top of the 5 channel deposit sequences, lithofacies of types Sr and Sl become abundant, sepresenting the 6 waning of the flow and overbank deposits over the floodplains. Lithofacies type Ss appears rarely 7 in the floodplains, corresponding to confined flows, possibly from sporadic events of increased 8 energy, forming scour deposits. Lithofacies type Sb can appear in any combination with the ones 9 above, representing a halt of the sedimentation and the colonisation of those beds by burrower 10 invertebrates and/or plants. Lutite lithofacies type Fm corresponds to settled sediments in the 11 floodplains, although in some parts the slightly more energetic lithofacies type Fl can also appear. 12 Lithofacies of types Fr and Fb represent the reworking of floodplain lutites by plant roots and 13 invertebrate burrows, respectively, indicating periods of very little sedimentation or subaerial 14 exposure. Finally, lithofacies type P culminates this biogenic occupation of the soils, with very 15 abundant carbonate nodules and even calcretes, with occasional gleyed patches, indicative of 16 palaeosols formed under climatic conditions with low precipitation regimes (see Mack et al., 17 1993; Alonso-Zarza, 2003). Calcrete hardpans and large calcareous nodules appear only in the 18 lower and middle parts of the Port des Canonge Formation, and in the upper part nodules are 19 generally smaller. Architectural element LA represents point bar deposits, LV+CR+CS correspond 20 to levée, crevasse channel and crevasse splay deposits, SS has been interpreted as sheetflood 21 deposits, and FF as floodplain fine sediments (playas and playa lakes). 22 The fining-upwards sequences with thick lutitic packs corresponding to floodplain deposits, the 23 abundance of lateral accretion surfaces in the vast majority of the sandstone channel deposits 24 (Figures 2D, 2E, 2F), and the fact that those surfaces dip mostly perpendicular to the main 25 palaeocurrent trend (NE/SW vs. SE: Calafat, 1988), point to fine-grained sandy meandering river 26 systems (Miall, 2006) as the main palaeoenvironment recorded in the Port des Canonge 27 Formation. During the dry season, the swales and chute channels were ponded or even completely 28 desiccated, as evidenced by the development of large mud cracks and palaeosols in the bar top 29 lutites. Those ponds probably functioned as waterholes, and in some occasions they were 30 intensely trampled by tetrapods (Matamales-Andreu et al., 2021d). The palaeocurrents measured 31 in this formation (n = 50) show a wide dispersion but with a general trend towards the South–East 32 (mean of 149.2º; see ‘8. Discussion’ below). 33 34 4.3. Pedra de s’Ase Formation 14 1 This formation (Figure 3) can be identified in the field because the sandstones form thick 2 packages, they are usually medium-grained and their colour is usually yellowish, white, blue or 3 pink (contrary to the red sandstones of the two other Permian formations of Mallorca). Lutites are 4 comparatively less frequent, and they can either be red or blue in colour. 5 4.3.1. Location and boundaries 6 The two largest outcrops of the Pedra de s’Ase Formation are at the Racó de s’Algar–Pedra de 7 s’Ase section (190.8–202.8 m, Figures 1B, 3B) and at the Port des Canonge–Hort de sa Cova 8 section (167.5–225.2 m, Figures 1D, 3D). Other important sites are those including Pedrera de sa 9 Cova (100.4 m, Figures 1D, 3E) and Marina de Valldemossa (70 m, Figure 1C) sections. There 10 are smaller outcrops at Na Vermella (Figure 1C), at Platja de sa font Figuera (Figure 1C) and at 11 Platja des Mabres (Figure 1D), although they are heavily affected by tectonics and are in some 12 cases mostly covered. The Racó de s’Algar–Pedra de s’Ase section is the thickest and the one 13 least affected by tectonics and, although it is at some points quite inaccessible (flooded and 14 vertical passes), it is here formally defined as the stratotype for this formation (Figure 3). Its lower 15 boundary has been described in ‘4.2. Port des Canonge Formation’. Its upper boundary probably 16 crops out at Pedrera de sa Cova (Figure 3E) in the form of an unconformable contact that gives 17 way to the pink–white sandstones of the Triassic Punta Roja Formation (Matamales-Andreu et 18 al., 2021b). Its minimum thickness is about 200 m and its total thickness is difficult to precisely 19 establish because the section, including the top of the formation, cannot be reliably correlated 20 with the rest. 21 4.3.2. Lithological features and palaeontological content 22 In this formation, all the lithofacies (Figure 4, Table 1) broadly represent the same depositional 23 processes and environments as those of the Port des Canonge Formation (see ‘4.2. Port des 24 Canonge Formation’ above), although their grain size is almost always coarser and the floodplain- 25 related deposits are scarcer (Figure 4D, 4F, 4G, 4J, 4K, 4M). Apart from that, the most remarkable 26 difference is the appearance of blue or, very rarely, greenish lutites, horizontally laminated and 27 rich in organic matter (lithofacies type Fl, Figure 4L), that represent sedimentation in oxbow 28 lakes. Lithofacies type P contains abundant invertebrate burrows, rhizocretions, carbonate 29 nodules (diameter of 1–3 cm) and, occasionally, gleyed patches. The dominant architectural 30 elements (Table 2) are SS, representing sheetflood deposits, and LA, corresponding to point bar 31 deposits. Secondarily, elements LV+CR+CS and FF also appear as overbank deposits. In the 32 Pedra de s’Ase Formation, sheetflood/channel sandstone deposits are dominant at the type section 33 (Racó de s’Algar–Pedra de s’Ase), whereas at the Port des Canonge–Hort de sa Cova section the 34 overbank deposits are almost as frequent as the sheetflood/channel deposits, contrary to the 15 1 underlying formation. Plant fossils, usually in the form of unidentifiable debris, are very common 2 in the Pedra de s’Ase Formation. Towards the middle part of the unit, some blue lutite beds have 3 yielded palynomorphs. Rhizocretions and invertebrate trace fossils are abundant in the beds 4 representing floodplain and crevasse splay deposits, which can also sporadically contain plant 5 impressions and tetrapod tracks. Complete and fragmentary tetrapod bones rarely appear in the 6 breccia beds. 7 4.3.3. Interpretation 8 The palaeoenvironments represented by this formation are also river systems with meandering 9 channels, although their grain size is distinctly coarser than in the underlying Port des Canonge 10 Formation. The common stacking of the channels, and the fact that floodplain deposits (red lutites 11 and very fine to fine-grained sandstones) appear less frequently, point to a general prograding 12 trend. This is perhaps related to a combined increase of both the subsidence rate of the basin and 13 the sediment input (e.g., Miall, 2006). The palaeocurrents measured in this formation (n = 50) 14 show a rough trend towards the South (mean of 171.2º; see ‘8. Discussion’ below). Floodplain 15 settings had a rich biota, as indicated by the relative high abundance of rhizocretions and 16 invertebrate traces, and sporadic occurrences of plant impressions, tetrapod tracks and bones. 17 Fluvial channels probably transported large logs and other plant fragments, and oxbow lakes 18 preserved a relatively rich record of microflora. 19 20 21 5. Magnetostratigraphy 22 The NRM intensity of the demagnetised specimens generally ranged from 10 × 10 -4 to 88 × 10-4 23 A/m. Upon demagnetisation, NRM intensity decreases somewhat after the first heating step at 24 150 °C in most demagnetised specimens (Figure 5A, C, D) but is noticeable in other samples 25 (Figure 5B) and may account for 30% NRM intensity loss. This may be an indication of goethite 26 carrying a spurious secondary magnetisation. Then, stepwise AF demagnetisation up to 100 mT 27 does not remove any remanence in some specimens (Figure 5A, C), whereas in other specimens 28 there is a slight decrease removing a relatively steep and downward component (Figure 5B, D) 29 denoting the presence of a minor magnetite-like phase. Finally, thermal demagnetisation defines 30 a straight line toward the origin of the demagnetisation diagram, which is always southerly 31 directed and shallowly upward in the 640–690 °C range that is ascribed to hematite, likely of 32 detrital origin (Figure 5A, C). This high temperature component conforms the ChRM direction. 33 However, in many samples (74 out of the 144 demagnetised samples), remanence removal in the 16 1 300–640 °C range delineates a trajectory that does not trend towards the origin of the 2 demagnetisation diagram and describes a great circle in stereographic projection. In such cases, 3 further demagnetisation at higher temperature does not clearly define the ChRM (Figure 5B, D), 4 and thus the ChRM directions have been calculated using the McFadden & McElhinny (1988) 5 great circle technique, implemented in the Paleomagnetism.org software. It is argued that the 6 carrier of this medium temperature component, which has to be of high coercivity attending the 7 demagnetisation protocol as discussed above, may be hematite of chemical origin that would carry 8 an undefined secondary magnetisation. 9 Figure 6 shows all ChRM computed directional data and derived VGP latitude plotted along 10 corresponding lithological logs and in stereographic projections (see also Supplementary Table 11 2). The lack of sufficient bedding differences among the three sections precludes a fold test, and 12 statistical parameters at specimen-level in geographic and tectonic coordinates are similar (Figure 13 6B). Yet, the high temperature of the unblocked ChRM that suggests detrital hematite as the main 14 magnetic carrier and its shallow inclination, which would be incompatible with an age older than 15 Triassic, indicates that the ChRM directions are primary. All ChRM directions are reverse and 16 conform to the Kiaman reverse polarity Superchron (see ‘8. Discussion’ below). Note that the 17 boundary of the Port des Canonge Formation and the Pedra de s’Ase Formation is included in 18 both the Racó de s’Algar–Pedra de s’Ase and in the Port des Canonge–Hort de sa Cova sections. 19 Consequently, the magnetostratigraphy from the first should overlap that from the latter section. 20 In this scenario, the interval with no data due to lack of outcrops at the Port des Canonge–Hort de 21 sa Cova section (290–235 m) is completed by the other section, assuming thickness of formations 22 and intervals are comparable. Stereograms of ChRM directional data and VGPs from all analysed 23 specimens divided for the three main sections are here presented in Supplementary Figure 1. For 24 full ChRM data and statistics see Supplementary Table 2 and Supplementary Table 3. 25 Some rockmagnetic experiments have been performed and are illustrated in Supplementary 26 Figure 2. Thermomagnetic heating curves (Supplementary Figure 2A–B) appear blurred due to 27 the low measured values close to the sensitivity of the instrument, and only a clear decrease below 28 about 120 °C is seen. A subtle decrease above 640 °C as indication of hematite is doubtful. 29 Heating curves are irreversible as cooling curves show increased values denoting the formation 30 of new ferromagnetic phases upon heating. Two clear differentiated phases with Curie 31 temperatures of about 580 °C and 420–450 °C are observed particularly for sample PC75A 32 (Supplementary Figure 2B). The presence of high coercivity phases is clearly illustrated by the 33 acquisition of isothermal remanent magnetisation (IRM) curves and corresponding backfield 34 IRMs (Supplementary Figure 2B–C). IRM acquisition curves do not saturate at the maximum 35 fields applied (1.2 T) and coercive force Hc values around 400–450 mT fall in the range of 17 1 hematite (Özdemir & Dunlop, 2014). Unmixing of the magnetic coercivity distributions of the 2 backfield IRM is best modelled by three components (Supplementary Figure 2D–E). The 3 predominant component (component_1) has coercivity log(B) values around 2.69 mT (B = 494 4 mT). Another two components have slightly higher and lower coercivity respectively 5 (component_2, log(B)/(B) of 2.92 mT/870 mT, and component_3 log(B)/(B) of 2.23 mT/176 6 mT). These three relatively high coercivity components could correspond to different types of 7 hematite or grain sizes. 8 9 10 6. Palaeobotany 11 6.1. Palynology 12 For the present work, only five out of 35 collected samples yielded palynomorphs (Figure 7), as 13 most of the sampled lithologies are too coarse-grained and oxidised to preserve any organic 14 remains. In general, the sporomorphs are severely damaged and altered, and the palynomorphs 15 are heavily oxidised. The samples yielding palynomorphs from the Pedra de s’Ase log, P-PA-05, 16 P-PA-09 and P-PA-12, are relatively well preserved, with up to 20 different taxa (Supplementary 17 Table 4). The samples P-CO-03 and P-CO-04 from the Pedrera de sa Cova log are poorly 18 preserved, but it has been possible to recognise at least some sporomorphs and identify them at 19 genus and/or species level (Supplementary Table 4). 20 The palynological assemblages, with almost 30 genera and almost 40 taxa (Table 3), show how 21 diverse the local and regional flora was, despite poor preservation of the macroremains (see ‘6.2. 22 Macroplant remains’ below). The palynological assemblages are dominated, both quantitatively 23 and qualitatively, by pollen grains (see Supplementary Table 4), as was previously pointed out by 24 Ramos & Doubinger (1989). Most of them are non-taeniate bisaccate pollen grains such as 25 Alisporites, Klausipollenites, Jugasporites, Gigantosporites and Minutosaccus. Taeniate pollen 26 grains are less abundant (but certainly more abundant than spores) and include, among others, the 27 genera Lueckisporites, Strotersporites and Protohaploxypinus. Other bisaccate pollen grains such 28 as Limitisporites and specimens assigned doubtfully to Triadispora are rare. Asaccate, costate 29 pollen grains such as Vittatina or other genera such as Marsupipollenites are very rare. The spores 30 are rare and poorly diverse; the only genera that could be identified are Endosporites, 31 Granulatisporites, Osmundacidites and Reticulatisporites. 32 Among the samples from the Pedra de s’Ase log, P-PA-05 and P-PA-09 are the two with the most 33 diverse palynological assemblages (20 and 19 taxa, respectively), whereas the sample P-PA-12 is 18 1 less well preserved, with only 14 different identified taxa (Supplementary Table 4). The two 2 samples from the Pedrera de sa Cova log (P-CO-03 and P-CO-04) are less diverse and yielded 3 eight and four different taxa, respectively (Supplementary Table 4). Only Lueckisporites virkkiae 4 is present in all samples yielding sporomorphs, and Klausipollenites schaubergeri and 5 Limitisporites sp. are present at least in four of the five samples. Other taxa are present in only 6 one of the samples, suggesting that they are rare in the palynological assemblages: among the 7 spores, Endosporites sp., Osmundacidites sp. and Reticulatisporites sp., and among the pollen, 8 Falcisporites zapfei, Gardenasporites leonardii, Jugasporites delasaucei, Jugasporites sp., 9 Limitisporites rectus, Lueckisporites globosus, Marsupipollenites sp., Minutosaccus sp. 1, 10 Paravesicaspora sp., Platysaccus leschikii, Playfordiaspora cancellosa, Protohaploxypinus 11 limpidus, Protohaploxypinus sp., Striatoabieites richteri, Strotersporites sp., Vitreisporites sp., 12 Vittatina sp., and doubtful assignements to the taxa Cordaitina sp. and Triadispora spp. 13 A comparison with previous papers of Permian rocks of Mallorca (Ramos & Doubinger, 1989; 14 Diez, 2000; Juncal, 2019) (see Supplementary Table 4) shows that several taxa had already been 15 mentioned before, such as the lycophyte genus Endosporites, whereas several fern genera such as 16 Granulatisporites and Osmundacidites and putative bryophytes (Reticulatisporites) are reported 17 here for the first time. On the other hand, some sphenophyte (Calamospora), lycophyte 18 (Kraeuselisporites, Lundbladispora) and fern (Deltoidospora) spores, which were already known 19 from the area, could not be identified in the samples studied for the present work. There is a close 20 resemblance among the previous and the new assemblages, at least at a genus level. The genera 21 ?Bascanisporites, Crucisaccites, Crustaesporites, Maculatasporites, Platysaccus, 22 Potonieisporites, Sahnisporites, Striatoabieites, Striatopodocarpites, Taeniaesporites and 23 Tiwariasporis were previously listed from the area (Diez, 2000; Juncal, 2019), whereas 24 Gigantosporites, Limitisporites, Marsupipollenites, Minutosaccus and ?Triadispora have been 25 identified here for the first time (Supplementary Table 4). With the exception of 26 Marsupipollenites (Glossopteridales), these palynomorphs were all produced by primitive 27 conifers (Table 3). 28 29 6.2. Macroplant remains 30 Well-preserved plant remains are very scarce in both the Port des Canonge and Pedra de s’Ase 31 formations. In the former, Calafat (1988) mentioned unidentifiable carbonaceous debris, and from 32 the latter, previous authors (Freeman & Obrador, 1979; Calafat, 1988; Ramos, 1995; Diez, 2000) 33 mentioned and illustrated large carbonised tree logs from a specific bed near Cova des Carbó, 34 which has been found again in the present work (Figure 8A). This work is the first to report plant 35 shoots preserved as impressions in very fine-grained sandstones, which are described below. 19 1 2 Sphenophyta indet. 3 Figure 8B 4 Studied material: Several internal casts with surrounding organic material, preserved with random 5 orientation in the sedimentary strata, left in the field. From the Pedra de s’Ase log (metre 81.0), 6 middle part of the Pedra de s’Ase Formation, Roadian–Wordian. 7 Description: The stems are tens of decimetres long and few decimetres wide, the internal cast 8 comprises yellowish to grey sandstone, surrounded by a few millimetres-thick organic film. No 9 ornamentation is evident on the surface. 10 Remarks: Several of the stems probably belong to sphenophytes, although the surface is too badly 11 preserved to show the casts of the vascular bundles. Although no clear distinction in nodes and 12 internodes can be distinguished, this could be due to the broken surface that could also partly 13 conceal them. 14 15 Genus Hermitia Kerp et Clement-Westerhof in Visscher et al., 1986 16 Hermitia sp. 17 Figure 8C–D 18 Studied material: DA/21-15-05-01. From the Torrent de na Nadala log (metre 25.6), upper part 19 of the Port des Canonge Formation, Artinskian–Kungurian. DA/21-15-05-03, DA/21-15-05-04 20 and DA/21-15-05-05. From the Torrent de na Nadala log (ex situ rock probably corresponding to 21 metre 34.0), upper part of the Port des Canonge Formation, Artinskian–Kungurian. 22 Description: Three foliated penultimate shoot fragments of Hermitia sp. are preserved as coarse 23 impressions in a reddish very fine-grained sandstone. The pinnately branched shoot fragments are 24 up to 70 mm long with alternatively inserted two series of ultimate shoots up to 45 mm long, 25 which arise at an angle of 45–60° from the axes. Leaves of ultimate shoots are needle-like, S- 26 shaped and spirally arranged, 2–5 mm long and about 1 mm wide. 27 Remarks: The material is very fragmentary and badly preserved, with no organic material 28 preserved. Nonetheless, the plant fossils show the typical pinnate architecture of the shoots and 29 the narrow, needle-like leaves. The general morphological features mostly resemble 30 Ernestiodendron filiciformes (Sternberg) Florin, 1934 emend. Clement-Westerhof, 1984. The fact 31 that no epidermal features or reproductive structures are preserved, supports the assignment to the 32 genus Hermitia, erected by Kerp & Clement-Westerhof (in Visscher et al., 1986) to accommodate 20 1 remains previously assigned to the genus Walchia, which preserve no epidermal features and 2 therefore can only be diagnosed in terms of leaf morphology (Visscher et al., 1986). 3 4 Genus Feysia Kerp et Clement-Westerhof in Visscher et al., 1986 5 ?Feysia sp. 6 Figure 8E–I 7 Studied material: DA21/15-03-01, DA21/15-03-02, DA21/15-03-03, DA21/15-03-04, DA21/15- 8 03-05, DA21/15-03-06, DA21/15-03-07 and DA21/15-03-09. From the Racó de s’Algar log 9 (metre 68.9), middle part of the Port des Canonge Formation, Artinskian–Kungurian. DA21/15- 10 04-02. From the Racó de s’Algar area (ex situ rock), middle–upper part of the Port des Canonge 11 Formation, Artinskian–Kungurian. DA21/15-05-06. From the Torrent de na Nadala log (ex situ 12 rock probably corresponding to metre 34.0), upper part of the Port des Canonge Formation, 13 Artinskian–Kungurian. DA21/15-08-05, DA21/15-08-06 and DA21/15-08-07. From the Platjola 14 des munt de Pedres area (ex situ rock), upper part of the Port des Canonge Formation, Artinskian– 15 Kungurian. DA21/15-15-01 and three other specimens left in the field. From Es Tamarell log (ex 16 situ rock probably corresponding to metre 18.0), lower part of the Pedra de s’Ase Formation, 17 Roadian–Wordian? 18 Description: Shoot fragments preserved as coarse impressions. The ultimate shoot fragments are 19 30–180 mm long with spirally arranged bifacial leaves, which arise with an angle of 40–65° and 20 can turn, in the upper part, slightly toward the apex. Leaves are linear with a slightly smooth apex, 21 5–20 mm long and 0.5–1.5 mm wide. One specimen that is 72 mm long and 11 mm wide has 22 spirally arranged lanceolate to triangular leaves with a slightly pointed apex, up to 6.5 mm long 23 and 2 mm wide. 24 Remarks: The plant remains are very fragmentary and preserved only as impressions with no 25 organic material. The shoot fragments show characteristic linear, long leaves that are spirally 26 inserted. The most similar specimens were figured as Pseudovoltzia sp. by Bercovici et al. (2009) 27 from the upper Permian of Menorca (Balearic Islands, western Mediterranean). However, the 28 specimens of Bercovici et al. (2009) not only show the typical gross morphology of 29 Pseudovoltzia, but are coalified and preserve a coaly film suggesting the presence of a cuticle, 30 even if the latter is not figured nor described. The specimens of Mallorca studied here, on the 31 other hand, do not permit the extraction of cuticle. Pseudovoltzia liebeana (Geinitz) Florin, 1927, 32 from the upper Permian of Germany, closely resembles the impressions of Mallorca in the general 33 shape of the leaves (slightly lanceolate to linear with a slightly pointed apex) and in the loose 21 1 spiral of attachment of the leaves (see Schweitzer, 1962, for a detailed description). The 2 specimens studied here, however, have much smaller and triangular leaves in the original conifer 3 shoots (Broutin & Kerp, 1994). This rather supports an assignment to the genus Feysia, since the 4 latter was created for conifers with bifacial leaves that are spirally arranged and are broad 5 triangular, oblong to obovate in shape with a constricted base. Most importantly, this genus 6 includes those broad-leaved conifer shoots for which no cuticle is known. Macromorphologically 7 very similar are the fragments of ultimate conifer shoots figured by Forte et al. (2018: fig. 10D) 8 as Quadrocladus sp. from the Kungurian of the Southern Alps. Within the genus Quadrocladus 9 Mädler, 1964, the most similar species is Quadrocladus orobiformis (Schlotheim) Schweitzer, 10 1962, typical of the upper Permian of the Central European Basin. Our specimens resemble 11 Quadrocladus orobiformis in the loose spiral manner in which the leaves are attached and in the 12 bifacial, linear shape of the leaves. The specimens from Mallorca and the Central European Basin 13 differ, however, in the looser spiral with a wider angle (almost 90°), as well as in the more linear 14 shape with a more rounded leaf apex of the latter. Unfortunately, similar to Pseudovoltzia, the 15 genus Quadrocladus is a conifer with well-known cuticles and a general morphological similarity 16 is not sufficient for a genus-level identification in Permian conifers. 17 18 19 7. Trace fossils 20 7.1. Invertebrate traces 21 In the sequences of the Port des Canonge Formation studied here, invertebrate bioturbation is 22 abundant in most of the beds representing crevasse splay deposits and floodplain fine deposits, 23 and even in the upper part of some channel sequences. In the Pedra de s’Ase Formation, on the 24 other hand, invertebrate burrows are less common and appear restricted to the red sandstone and 25 lutite intervals between medium-grained whitish sandstone channel deposits. Ramos & García- 26 Ramos (1992) reported the presence of the ichnogenera Ancorichnus Heinberg, 1974, 27 Palaeophycus Hall, 1847, and Planolites Nicholson, 1873. Of these, only the latter two have been 28 observed in the course of the present work, together with the four other ichnotaxa described here. 29 30 Ichnogenus Arenicolites Salter, 1857 31 Arenicolites isp. 32 Figure 9A 22 1 Studied material: Numerous specimens, left in the field. From the Port des Canonge–Hort de sa 2 Cova log (metre 494.2), among others, middle part of the Pedra de s’Ase Formation, Roadian– 3 Wordian. 4 Description: Vertical, straight, unbranched, cylindrical burrows (diameter between 10–30 mm) 5 filled with a sediment with a texture slightly different to that of the surrounding matrix (both very 6 fine-grained sandstones), and almost always evident as paired circular openings on the bedding 7 surface (similar to those illustrated by Díez-Canseco et al., 2016). 8 Remarks: The lack of complete specimens in lateral section has precluded ichnospecies-level 9 identification. The tracemakers of this ichnogenus are considered to be suspension-feeding and 10 deposit-feeding worms and crustaceans (Díez-Canseco et al., 2016 and references therein). 11 12 Ichnogenus Cochlichnus Hitchcock, 1858 13 Cochlichnus anguineus Hitchcock, 1858 14 Cochlichnus anguineus 15 Figure 9B 16 Studied material: Six specimens, left in the field. From the Torrent de na Nadala log (metre 26.5), 17 upper part of the Port des Canonge Formation, Artinskian–Kungurian. 18 Description: Convex hyporelief (natural cast) in the base of a medium-grained sandstone bed, 19 corresponding to thin (about 1.2 mm wide), sinuous (wavelength 6.2–7.5 mm) grooves made on 20 the sediment. 21 Remarks: This ichnotaxon occurs rarely and has only been observed on the base of one sandstone 22 bed with climbing ripples corresponding to a point bar deposit, filling the surface of the 23 underlying lutites. Laterally in the same bed, there are abundant tetrapod tracks and large mud- 24 cracks. Nematodes and/or dipteran insect larvae are considered to be the most probable 25 tracemakers of this trace (Uchman et al., 2004 and references therein). 26 27 Ichnogenus Cruziana d’Orbigny, 1842 28 Cruziana isp. 29 Figure 9C 23 1 Studied material: One specimen, left in the field. From a recently fallen, ex situ block 2 corresponding to the metres 95.0–97.0 of the Port des Canonge–Hort de sa Cova section, and thus 3 in a channel deposit of the lower part of the Port des Canonge Formation, Sakmarian–Kungurian? 4 Description: Traceway preserved as a convex hyporelief on the base of a medium-grained 5 sandstone bed. The observed morphotype corresponds to a bilobate trace about 20 mm wide, 6 displaying a central longitudinal ridge with a furrow on each side. On each of the furrows, there 7 are two rows of small impressions, anterolaterally enlongated, probably made by the tips of the 8 appendices of the tracemaker. 9 Remarks: The only specimen studied here has not been identified to ichnospecies level because 10 of its poor preservation. Given its size, this trace may have been produced by notostracan 11 crustaceans, similar to those described from the Massif Central (Gand et al., 2008). 12 13 Ichnogenus Palaeophycus Hall, 1847 14 Palaeophycus tubularis Hall, 1847 15 Palaeophycus tubularis 16 Figure 9D 17 Studied material: Numerous specimens, left in the field. From the Port des Canonge–Hort de sa 18 Cova log (metre 570.0), among others, upper part of the Pedra de s’Ase Formation, Roadian– 19 Wordian. 20 Description: Relatively small (diameter of 5–10 mm), cylindrical, linear to slightly sinuous 21 burrows, which are sometimes branched, have smooth thin walls, are oblique or horizontal to 22 stratification, and their filling is the same as the surrounding matrix (very fine- to medium-grained 23 sandstone). 24 Remarks: The specimens observed in Mallorca correspond to the ichnospecies Palaeophycus 25 tubularis because their walls are smooth and thin (see Pemberton & Frey, 1982). It has been 26 observed sporadically in the sandstone deposits of the upper part of channel sequences, both in 27 the Port des Canonge Formation and in the Pedra de s’Ase Formation. In continental settings, 28 these traces have been interpreted as a dwelling structure, possibly made by orthopteran, 29 hemipteran or coleopteran insects (Krapovickas et al., 2008 and references therein). 30 31 Ichnogenus Planolites Nicholson, 1873 24 1 Planolites beverleyensis (Billings, 1862) 2 Planolites beverleyensis 3 Figure 9E 4 Studied material: Numerous specimens, left in the field. From the Pedra de s’Ase log (metre 3.0), 5 among others, lower part of the Pedra de s’Ase Formation, Roadian–Wordian. 6 Description: Cylindrical, large (diameter between 5–15 mm), linear to slightly sinuous, usually 7 umbranched, smooth, horizontal or oblique, unwalled burrows with a filling that is slightly 8 different to that of the surrounding matrix (lutites, very fine- or fine-grained sandstones). 9 Remarks: Overall, this ichnospecies is dominant in the floodplain deposits of all studied sections, 10 both in the Port des Canonge Formation and in the Pedra de s’Ase Formation. It corresponds to 11 this ichnospecies because they are relatively large, straight to gently curved burrows (see 12 Pemberton & Frey, 1982). This ichnogenus is thought to have been produced by deposit-feeder 13 vermiform organisms (Díez-Canseco et al., 2016 and references therein). 14 15 Ichnogenus Taenidium Heer, 1877 16 Taenidium barretti (Bradshaw, 1981) 17 Taenidium barretti 18 Figure 9F 19 Studied material: Several specimens, left in the field. From the Pedra de s’Ase log (metre 61.5), 20 middle part of the Pedra de s’Ase Formation, Roadian–Wordian. 21 Description: Slightly sinuous to winding, unbranched, unwalled, horizontal burrows (width of 22 about 10 mm) with a meniscate backfill (with short, arcuate and densely-packed menisci) filled 23 with similar sediment to that of the surrounding matrix (medium-grained sandstones). 24 Remarks: This ichnospecies has been identified in a crevasse splay sandstone deposit in a 25 floodplain interval of the middle part of the Pedra de s’Ase Formation. The specimens are similar 26 to what Ramos (1995) figured as Ancorichnus, which is characterised by a thick wall (e.g., Boyd 27 & McIlroy, 2017) that is not observed in the ones studied here. In continental environments, 28 Taenidium is thought to have been produced by coleopterans (Baucon et al., 2014) aestivating in 29 moist sediment during dry periods (Minter et al., 2007). 30 25 1 7.2. Ichnofacies 2 The ichnofossils recognised in the present study can be attributed to different kinds of ichnofacies 3 (Buatois & Mángano, 1998), making it possible to infer the palaeoenvironment in which they 4 were formed. Among the recognised invertebrate trace fossils, Arenicolites isp. is a representative 5 of the Skolithos ichnofacies, typical of high-energy environments (Buatois & Mángano, 1998), in 6 this case crevasse splay lobes. Cruziana isp., Taenidium barretti and the tetrapod tracks (see ‘7.3. 7 Tetrapod tracks’ below) are indicative of the Scoyenia ichnofacies, representing areas with 8 periodic flooding and desiccation (Buatois & Mángano, 1998). Finally, Cochlichnus anguineus, 9 Palaeophycus tubularis and Planolites beverleyensis are indicative of the Mermia ichnofacies, 10 typically developed in deposits with more persistent water bodies (Buatois & Mángano, 1998). 11 Therefore, in the studied sequences, the Skolithos ichnofacies was probably established on freshly 12 deposited crevasse splays, the Scoyenia ichnofacies corresponded to the margins of channels and 13 playa lakes, and the Mermia ichnofacies developed in the deepest parts of the relatively shallow 14 playa lakes and swales. 15 16 7.3. Tetrapod tracks 17 In the Permian deposits of Mallorca, ichnogenus-level identifiable tetrapod ichnites have so far 18 only been found at the Racó de s’Algar–Pedra de s’Ase section. There, 15 beds with tracks have 19 been located in the upper part of the Port des Canonge Formation, and two other beds have been 20 observed in the lower part of the Pedra de s’Ase Formation. In almost all cases, they are preserved 21 in convex hyporelief (natural casts) on the base of very fine- to fine-grained sandstone beds 22 corresponding to crevasse splay deposits, which record the surface of underlying lutite beds where 23 the tracks were originally imprinted. In only two cases the ichnites are preserved as concave 24 epireliefs on the surface of very fine-grained sandstones. Calafat et al. (1986, 1986–1987) and 25 Calafat (1988) were the first to report some of the tracksites here studied, but they provided only 26 preliminary identifications. In Supplementary Figure 3 we present pictures taken by those authors 27 in the 1980s. Most of these ichnites no longer exist. 28 29 Ichnogenus Hyloidichnus Gilmore, 1927 30 Hyloidichnus bifurcatus Gilmore, 1927 31 Hyloidichnus bifurcatus, large morphotype 32 Figure 10A–C; Supplementary Table 5 26 1 Studied material: NA-25.6-01a, NA-25.6-01b, NA-25.6-01c, NA-25.6-01d, NA-25.6-01e, NA- 2 25.6-01f (natural cast of a trackway with two left manus-pes sets, a right manus track and a right 3 pes track). From the Torrent de na Nadala section (metre 25.6), upper part of the Port des Canonge 4 Formation, Artinskian–Kungurian. NA-26.0-02c, NA-26.0-02d, NA-26.0-02e (natural cast of a 5 partial trackway with a left manus-pes set and a right pes track). From the Torrent de na Nadala 6 section (metre 26.0), upper part of the Port des Canonge Formation, Artinskian–Kungurian. NA- 7 77.5-01a, NA-77.5-01b, NA-77.5-01c, NA-77.5-01d (natural cast of a partial trackway with two 8 left manus-pes sets) and NA-77.5-01e (natural cast of a right pes track). From the Torrent de na 9 Nadala section (metre 77.5), upper part of the Port des Canonge Formation, Artinskian– 10 Kungurian. PM-15.7-01a, PM-15.7-01b (natural cast of a right manus-pes set). From the Punta 11 d’en Pere Mir section (metre 15.7), lower part of the Pedra de s’Ase Formation, Roadian– 12 Wordian? 13 Description: Pes imprint semiplantigrade, pentadactyl, ectaxonic and slightly wider (ca. 10–12 14 cm) than long (ca. 7–10 cm). The digit imprints are relatively stout, straight and long, especially 15 in the case of digits III and IV. The imprints of digits I and II are usually only preserved 16 proximally, and that of digit V is either not present or preserved only as the tip. Their relative 17 lengths are ordered as follows: I