A Taxonomic Revision of Batropetes (Amphibia, Microsauria) from the Rotliegend (Basal Permian) of Germany

N. Jb. Geol. Paläont. Abh. 269/1 (2013), 73–96 Article Stuttgart, July 2013

A taxonomic revision of Batropetes (Amphibia, Microsauria) from the Rotliegend (basal Permian) of Germany

Sabine Glienke With 8 figures

Abstract: The genus Batropetes is one of the most completely preserved representatives of the micro- saur family Brachystelechidae. Previously, the only species to be described was Batropetes fritschi, based on 19 mostly poorly preserved specimens from the Döhlen Basin in eastern Germany, and one referred specimen from the Saar-Nahe Basin in western Germany. Reexamination of this material demonstrates that the referred specimen differs from the type material, and it is named Batropetes niederkirchensis n. sp. in this study. The two species differ in the shape of the prefrontal and postor- bital, the width of the interorbital region, the number of presacral vertebrae, the degree of ossification of the scapulocoracoid, and the position of the obturator foramen. The functional interpretation of the skull and the locomotion apparatus suggests that the genus was terrestrial, living near the lakes, where they are preserved in the sediments.

Key words: Microsauria, morphology, Saar-Nahe Basin, Döhlen Basin, palaeoecology.

1. Introduction & reisz 2003; anderson 2008; anderson et al. 2008), by others to the stem group of the Lissamphibia (Val- Most microsaurs are from the Upper Carboniferous lin & laurin 2004) and by other workers to be unre- and Lower Permian of North America and the Upper lated to any lissamphibians (ruta et al. 2003). Carboniferous of the Czech Republic. Until now, only The first discoveries of Batropetes were made in the genera Altenglanerpeton, Batropetes, Saxoner- the Döhlen Basin near Dresden in Saxony. They were peton and Tambaroter have been described from the described by Geinitz and deiCHMüller (1882) as Hy- European Lower Permian (Carroll & Gaskill 1971, loplesion Fritschia. In 1885 Credner used the name 1978; HenriCi et al. 2011; Glienke 2012). They are re- Hylonomus Fritschi and in 1890 he further established stricted to the Rotliegend of Germany. Batropetes is of the species Petrobates truncatus. In 1971, Carroll & great significance, because, of its relatively complete Gaskill changed the name Petrobates to Batropetes, preservation, it best represents the family Brachy- an anagram of Petrobates, but they mistook this ge- stelechidae, which also includes the genera Carrolla nus for a captorhinomorph reptile. Seven years later (lanGston & olson 1986; Maddin et al. 2011) and Carroll & Gaskill (1978) revised all specimens from Quasicaecilia (Carroll 1990) from the Lower Permi- the Döhlen Basin. They established the new genus an of Texas. This family is considered by some authors Saxonerpeton and some of the specimens they named to belong to the stem group of the Caecilia (anderson Brachystelechus fritschi, for which they stated signifi-