DOI: 10.15468/duudf6
title: Osteology of the Permian temnospondyl amphibian Glanochthon lellbachae and its relationships

description: This dataset contains the digitized treatments in Plazi based on the original journal article Schoch Correspondence, Rainer R. (2021): Osteology of the Permian temnospondyl amphibian Glanochthon lellbachae and its relationships. Fossil Record 24 (1): 49-64, DOI: 10.5194/fr-24-49-2021, URL: http://dx.doi.org/10.5194/fr-24-49-2021Abstract. The early Permian Meisenheim Formation of the Saar –Nahe Basin (Germany) is famous for its richness in vertebrate fossils, among which the temnospondyls were present with microvores and fish-eating apex predators. The latter trophic guild was occupied exclusively by the genus Sclerocephalus in that basin within a long time interval up to M8, whereas in M9, a new taxon, Glanochthon lellbachae, appeared. This taxon is defined by (1) a preorbital region 1.8–2.0 times as long as the postorbital skull table, (2) dermal ornament with tall radial ridges, (3) a prefrontal anteriorly wider with straight lateral margin, (4) a squamosal posteriorly only half as wide as the quadratojugal, (5) phalanges of manus and pes long and gracile, (6) carpals unossified in adults, and (7) tail substantially longer than skull and trunk combined. Phylogenetic analysis finds that G. lellbachae forms the basal sister taxon of the stratigraphically younger G. angusta and G. latirostre and that this clade nests within the paraphyletic taxon Sclerocephalus, with S. nobilis forming the sister taxon of the genus Glanochthon (urn:lsid:zoobank.org:act: 3038F794- 17B9-4FCA-B241-CCC3F4423651; registration date: 15 March 2021).1 IntroductionThe Saar –Nahe Basin ranks among the largest late Paleozoic sedimentary basins in continental Europe and has produced thousands of early Permian tetrapod fossils (Boy et al., 2012; Fig. 1). The largest tetrapod taxa in these lacustrine deposits were eryopiform temnospondyls, which formed the top predatory group that preyed on bony fishes (Boy, 2003). Among these, the most common genus, Sclerocephalus, evidently preferred actinopterygians, whereas the more gracile Glanochthon and Archegosaurus preserve acanthodian skeletons in their intestines (Boy, 1994; Kriwet et al., 2008; Schoch and Witzmann, 2009a). For more than 150 years, the three taxa were the only well-known eryopiforms from the Saar –Nahe Basin despite much collecting in numerous localities. The only exceptions formed two isolated finds, the still enigmatic Palatinerpeton (Boy, 1996) and a fragmentarily known Onchiodon -like eryopid (Schoch and Hampe, 2004).This changed when private collector Klaus Krätschmer discovered a new site in the Klauswald southwest of Odernheim am Glan (Fig. 1), where large quantities of vertebrates were collected. This locality falls within the Meisenheim Formation, the richest tetrapod-bearing rock sequence in the basin (Boy et al., 2012). He published a large part of his material (Krätschmer, 2004, 2006; Krätschmer and Resch, 2005) and compared it with other samples, providing detailed information also on the various localities and fossillagerstätten. His taxonomic considerations led him to suggest the existence of various new taxa, most of which turned out to be synonyms of Sclerocephalus haeuseri Goldfuss (Schoch and Witzmann, 2009a). Nevertheless, his work highlighted the variation between and within samples of eryopiform temnospondyls, and one of the new morphs from the Klauswald locality that he envisioned clearly forms a separate taxon from the co-occurring Sclerocephalus nobilis. This new species was first named Cheliderpeton lellbachae by Krätschmer (2006).The various samples of Sclerocephalus and Glanochthon span a time range of some 2.5 Myr (Boy et al., 2012; Menning and Bachtadse, 2012), and the morphological and developmental aspects of this endemic evolutionary lineage will be the subject of a research program that seeks to trace the microevolution and cladogenesis between the samples. TheFigure 1. Localities yielding Sclerocephalus and Glanochthon material and stratigraphy of the Rotliegend sequence with emphasis on the Meisenheim Formation (Autunian, Lower Permian) in the Saar–Nahe Basin of Germany.present exercise forms only the first step in this program. The objective is to describe and diagnose this taxon, especially in comparison to co-occurring S. nobilis from the same locality and to study its phylogenetic relationships.