A new “microsaur” (Amphibia; Lepospondyli) from the Rotliegend of the Saar–Palatinate region (Carboniferous/Permian transition; West Germany)

Abstract

Altenglanerpetonschroederi n. sp. is documented by a skeleton preserved in dorsal view from the Altenglan Formation of the Saar–Nahe Basin. The only known species of this new genus has a massive skull that is slightly longer than wide with a more or less triangular outline, without traces of lateral-line canals, with a small round orbit, very wide interorbital region, and the jugal extending far in front of the orbit. The long, undifferentiated trunk region comprises at least 30 lepospondylous presacral vertebrae. The pelvic girdle, hind limbs, and tail are not preserved. The forelimb is small and poorly ossified. The cladogram supports placement of Altenglanerpeton in the Recumbirostra. The new genus seems closest to Tambaroter, the Goniorhynchidae, and Brachystelechidae, with the largest number of morphological similarities shared with the Ostodolepidae, particularly with Micraroter and Pelodosotis.