A new amphibamiform (Temnospondyli: Branchiosauridae) from the lower Permian of the Czech Boskovice Basin

Abstract

ABSTRACT The temnospondyl clade Amphibamiformes includes small newt-like forms that dwelled in freshwater lakes in the Pennsylvanian and Lower Permian of Europe and North America. Here we report a new genus and species, Piasimotriton kochovi, from the early Permian Boskovice Basin, Czech Republic. It has a unique combination of characters, among which the following ones rank as most important: (1) extremely elongated basipterygoid process forming a paired elongate facet for articulation with basal plate, (2) parasphenoid with broad and much abbreviated basal plate, about 2.5 times wider than long, (3) tooth crown with lateral crest, (4) premaxilla with 18 tiny teeth, and (5) a strong dermal ornament on the median skull elements. Piasimotriton kochovi has probably pedicellate teeth. Phylogenetic analysis finds Piasimotriton nests with the Melanerpeton clade with Melanerpeton, Leptorophus, and Schoenfelderpeton, with “Melanerpeton” gracile forming its sister taxon. The possession of various features that are also found in lissamphibians indicates a more widespread distribution of these within their putative stem-group. The stomach content of Piasimotriton kochovi consists of segmented thorax remains of small crustaceans. Piasimotriton probably competed with osteichthyans for arthropod prey and was only present in a short time interval of the lake's existence.