Jaxtasuchus salomoni Schoch & Sues, 2014

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

Jaxtasuchus salomoni Schoch & Sues, 2014

Holotype.

SMNS 91352 A – C: largely articulated skeleton lacking the skull and cervical vertebrae on several blocks of mudstone. SMNS 91352 A and B are part and counterpart of a block with the anterior portion of the trunk including the forelimbs. SMNS 91352 C preserves the pelvic region, hindlimbs, and much of the tail.

Type locality.

Schumann Quarry, Eschenau, Vellberg municipality, Schwäbisch Hall district, Baden-Württemberg.

Type horizon.

Untere Graue Mergel, Bed E 6, Erfurt Formation, Lower Keuper Subgroup. Age: Middle Triassic (Ladinian: Longobardian).

Referred material.

SMNS 91083 , partial, disarticulated anterior portion of a skeleton including both maxillae, probable left postorbital, anterior part of the left nasal, posterior process of left premaxilla, right pterygoid, supraoccipital, basioccipital, both exoccipitals, and left angular; seven transverse rows of osteoderms, each comprising four elements; cervical vertebrae 2–8 and cervical ribs; SMNS 91002 , complete forelimb, dorsal osteoderms, and associated femur; SMNS 90500 , caudal osteoderms, two vertebrae, and two ribs; SMNS 81868 , dorsal vertebra; SMNS 81906 , 90046, two caudal vertebrae; SMNS 81891 –81905, 90530–90539, osteoderms; SMNS 90505 , dorsal vertebrae, numerous osteoderms, ribs, and possible gastralia; SMNS 90067 , 90068, two paramedian osteoderms; SMNS 59403 , lateral caudal osteoderm.

Diagnosis.

Distinguished by the following combination of features: maxillary tooth crowns tall, slightly recurved, bearing prominent apicobasal ridges along labial and lingual surfaces and smooth mesial and distal carinae (Fig. 10 C ); width of dorsal osteoderms up to 1.2–1.8 times greatest length; sculpturing pronounced on dorsal and caudal osteoderms, comprising prominent ridges and deep pits (Fig. 10 E ) that are more prominently developed but fewer in number than on comparable osteoderms of Doswellia kaltenbachi ; and cervical centra distinctly longer than high, with those of sixth and seventh cervical vertebrae being longest ( Schoch and Sues 2014; Ezcurra 2016).

Comments.

Jaxtasuchus salomoni represented the first record of a doswelliid archosauriform from the Middle Triassic and from the CEB. Among known doswelliids, it is most closely related to Doswellia kaltenbachi Weems, 1980 from the Upper Triassic (Carnian: Tuvalian) Poor Farm Member of the Falling Creek Formation in Virginia, U. S. A.

References.

Schoch and Sues (2014), Ezcurra (2016).

Figures

Figure 10. Reptiles from the Lower Keuper Subgroup. A. Stem-turtle Pappochelys rosinae, holotype (SMNS 91360), partial postcranial skeleton. Scale bar: 1 cm. B. Rhynchocephalian Wirtembergia hauboldae, holotype (SMNS 91313), right maxilla in lateral view. Scale bar: 2 mm. C. Doswelliid archosauriform Jaxtasuchus salomoni (SMNS 91083), maxillary tooth. Scale bar: 1 mm. D. Colognathid Quasicolognathus eothen, holotype (SMNS 97019), left maxilla and prefrontal and possible palatine in lateral view. Scale bar: 2 mm. E. Doswelliid archosauriform Jaxtasuchus salomoni (SMNS 91085), lateral dorsal osteoderm in dorsal view. Scale bar: 1 cm.