Incisor enamel microstructure places New and Old World Eomyidae outside Geomorpha (Rodentia, Mammalia)
Kalthoff, Daniela C. (Swedish Museum of Natural History. Department of Zoology)
Fejfar, Oldrich (Karls University. Geological-Paleontological Institute (Czech Republic))
Kimura, Yuri (Institut Català de Paleontologia Miquel Crusafont)
Bailey, Bruce E. (University of Nebraska State Museum. Division of Vertebrate Paleontology)
Mörs, Thomas (Swedish Museum of Natural History. Department of Paleobiology)

Date:	2022
Abstract:	The lower incisor enamel microstructure of the fossil rodent family Eomyidae was believed to be three-layered and highly derived but rather uniform throughout the clade. Here, we describe a new four-layered schmelzmuster in Eomyidae consisting of a three-fold portio interna with longitudinal oriented, uniserial Hunter-Schreger bands and a one-fold portio externa, accounting for a unique enamel microstructure character combination in Rodentia. This new schmelzmuster type has developed early in eomyid evolution and is detectable already in the late Eocene (Chadronian) of North America. In European eomyids, it first occurs in the early Miocene (MN 3), implying that this four-layered schmelzmuster was not present in all members of the family but restricted to species included in Eomyini and some genera currently considered Eomyidae incertae sedis within Eomyidae. Additionally, our analysis recognizes three taxa with schmelzmuster divergent from all other eomyids. Incisor enamel microstructure does not advocate a close phylogenetic relationship of Eomyidae to either fossil or extant Heteromyidae and Geomyidae, nor to fossil Heliscomyidae and Florentiamyidae. Our results rather support the view that Eomyidae are placed outside Geomorpha.
Grants:	Agencia Estatal de Investigación PID2020-117289GB-I00
Note:	Altres ajuts: CERCA Programme/Generalitat de Catalunya
Rights:	Aquest document està subjecte a una llicència d'ús Creative Commons. Es permet la reproducció total o parcial, la distribució, la comunicació pública de l'obra i la creació d'obres derivades, sempre que no sigui amb finalitats comercials, i sempre que es reconegui l'autoria de l'obra original.
Language:	Anglès
Document:	Article ; recerca ; Versió publicada
Subject:	Enamel microstructure ; Eurasia ; Neogene ; North America ; Paleogene ; Schmelzmuster
Published in:	Zoologica Scripta, Vol. 51, Issue 4 (July 2022) , p. 381-400, ISSN 1463-6409

DOI: 10.1111/zsc.12541

20 p, 11.6 MB

The record appears in these collections:
Research literature > UAB research groups literature > Research Centres and Groups (research output) > Experimental sciences > Institut Català de Paleontologia Miquel Crusafont (ICP)
Articles > Research articles
Articles > Published articles