Trachelosaurus fischeri Broili

Sues, Hans-Dieter & Schoch, Rainer R., 2025, Synopsis of the Triassic reptiles from Germany, Fossil Record 28 (2), pp. 411-483 : 411-483

Trachelosaurus fischeri Broili in Fischer & Broili, 1918

Holotype.

MLU. GeoS. 1612, partially disarticulated skeleton comprising a few isolated skull bones including a right premaxilla, much of the presacral vertebral column, two sacral vertebrae, several caudal vertebrae, gastralia ‘ basket, ’ right ilium, right? pubis, left? femur, and at least one probable metatarsal (Fig. 3 B ).

Type locality.

Merkel’s quarry, Bernburg an der Saale, Saxony-Anhalt,

Type horizon.

Platy sandstone unit within Chirotheriensandstein, upper part of Solling Formation, Middle Buntsandstein Subgroup. Age: Middle Triassic (Anisian: Aegean).

Diagnosis.

Distinguished by the following combination of features: presacral column comprising at least 21 cervical and 27 dorsal vertebrae; cervical and dorsal neural spines transversely expanded at their distal ends with strongly developed rugosities; cervical ribs with short bifurcating shafts, at most barely extending beyond corresponding vertebra; transverse processes of anterior to mid-dorsal vertebrae wide and ‘ wing-like’; torso barrel-shaped, formed by broadly rounded, almost uniformly holocephalous dorsal ribs; ilium lacking preacetabular process; and femur stocky, without curved shaft ( Spiekman et al. 2024).

Comments.

The high number of cervical vertebrae led Huene (1944 a) to argue that the holotype comprises skeletal remains of two individuals. Spiekman et al. (2024) published a detailed redescription of the holotype (which does represent a single individual), and their phylogenetic analysis recovered Trachelosaurus fischeri as the first record outside China of the tanysaurian clade Dinocephalosauridae, which was renamed Trachelosauridae based on the priority of the latter name.

References.

F. Huene (1902, 1944 a), Broili and Fischer (1918), Spiekman et al. (2024).

Figures

Figure 3. Reptiles from the Middle Buntsandstein Subgroup. A. Procolophonid Koiloskiosaurus coburgiensis, syntypes (NMC 9333), slab with molds of three associated partial skeletons. Scale bar: 10 cm. Photograph courtesy of D. Grabow (NMC). B. Trachelosaurid tanysaurian Trachelosaurus fischeri, holotype (MLU. GeoS. 1612), disarticulated skeleton. Scale bar: 20 cm. Photograph courtesy of S. N. F. Spiekman.