Wednesday, June 1, 2022

[Paleontology • 2022] Chemnitzion richteri • A New Basal Zatracheid Temnospondyl from the early Permian Chemnitz Fossil Lagerstätte, central-east Germany


Chemnitzion richteri 
Werneburg, Witzmann, Schneider & Rößler, 2022

Artwork by Frederik Spindler.

Abstract
A new zatracheid temnospondyl adds to the fossil-rich T0 assemblage of the Chemnitz Fossil Lagerstätte (Chemnitz Basin, Sakmarian–Artinskian transition). The skeleton was found in basal air-fall tuffs of the Zeisigwald Tuff (Leukersdorf Formation) and consists of the almost complete skull roof in dorsal view, parts of the occiput, fore and hind limbs, numerous presacral vertebrae and ribs, parts of the pelvic girdle and ventral scales. The new taxon Chemnitzion richteri gen. nov. et sp. nov. is proposed due to the following autapomorphic characters: (1) postorbital skull very short, about five times shorter than the preorbital skull; (2) elongate and robust hindlimbs, with femur length reaching almost half of the skull length. A phylogenetic analysis finds the new taxon at the base of a monophyletic Zatracheidae, forming a trichotomy with Acanthostomatops vorax and the more derived zatracheids [Zatrachys serratus + (Dasyceps bucklandi + D. microphthalmus)]. The animal was part of a diverse trophic web of plants, animals and microorganisms. Various vertebrates, arthropods and gastropods constituted a vital community that lived in a dense, seasonally influenced forest habitat dominated by tree-sized ferns, calamitaleans, medullosans and cordaitaleans. The temnospondyl’s death and taphonomic background is closely related to the ash-cloud deposition following a phreatoplinian eruption. The following massive pyroclastic flow finally entombed the moist forest and intensively heated all enclosed organic remnants.

Keywords: Terrestriality, Chemnitzion richteri gen. nov. et sp. nov., Zatracheidae, Skull roof sculpture, Powerful hind limb, Cisuralian, Volcanic taphonomy


Chemnitzion richteri gen. nov. et sp. nov., dorsal skull roof, skull length of 62 mm;
a, b skull with bones showing heat-derived cracks and blisters, and with rounded organic remains of the orbital sacs and of the intermaxillary gland sac, TA 0949b.

Reconstruction of the new zatracheid temnospondyl Chemnitzion richteri gen. nov. et sp. nov. in the last moments of its life, from the Permian Fossil Lagerstätte of Chemnitz, central-east Germany.
Artwork by Frederik Spindler.

Systematic palaeontology

Order Temnospondyli von Zittel, 1888
Family Zatracheidae Cope, 1882

Genus Chemnitzion gen. nov.

Etymology. The genus name aims to dignify the find locality, the city of Chemnitz—European Capital of Culture 2025.

Chemnitzion richteri gen. nov. et sp. nov. 

Etymology In honour of Mr Fred Richter, dedicated fossil collector for many decades and chairman of the friend’s circle board of the Museum für Naturkunde Chemnitz.

Locality and horizon. Chemnitz-Hilbersdorf excavation, Frankenberger Straße, central-east Germany; basal ash-tuff unit S5 of the Zeisigwald Tuff, Leukersdorf Formation, lower Rotliegend (Sakmarian–Artinskian transition, Cisuralian), Chemnitz Basin.
 

Ralf Werneburg, Florian Witzmann, Joerg W. Schneider and Ronny Rößler. 2022. A New Basal Zatracheid Temnospondyl from the early Permian Chemnitz Fossil Lagerstätte, central-east Germany. PalZ. DOI: 10.1007/s12542-022-00624-8