Nothosaurus mirabilis Münster, 1834

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

Nothosaurus mirabilis Münster, 1834

Holotype.

UMO BT 001000.00 , partial postcranial skeleton (N. Klein et al. 2022).

Type locality.

Oschenberg near Laineck (also known as Lainecker Berg or Lainecker Höhenzug), east of Bayreuth, Bavaria.

Type horizon.

Ceratites flexuosus through C. compressus zones , upper part of Trochitenkalk Formation and lower part of Meissner Formation, Upper Muschelkalk Subgroup. Geyer and Friedlein (2020) considered the Muschelkalk deposits exposed in the region of the Lainecker Höhenzug a distinct unit of marginal marine strata, which they refer to as Eschenbach Formation. The subformation that has yielded the holotype was named Eschenbach Formation 5. Age: Middle Triassic (Anisian: Illyrian).

Referred material (from Germany).

See list in Rieppel and Wild (1996) and N. Klein et al. (2022). This material includes the holotype of N. bergeri Meyer, 1855 ( GZG.V.756-1 ) and the syntypes of N. muensteri Meyer, 1839 (Rieppel 2002). Rieppel (1993) also reidentified Elmosaurus lelmensis F. Huene, 1957 as Nothosaurus cf. N. mirabilis . The holotype of the former ( SMNS 59077 ) was collected from the Upper Muschelkalk Subgroup of Lelm near Braunschweig, Lower Saxony.

Diagnosis.

Distinguished by the following combination of features: adult condylobasal length of cranium of up to 46 cm; rostrum long and slender with parallel lateral edges (Fig. 7 C, D ); length-to-width ratio of mandibular symphysis ranging from 1.5 to 1.7; premaxilla with five fangs; four small maxillary teeth preceding paired maxillary fangs; rostral constriction of snout weakly expressed; external nares long and slender; supratemporal fenestra elongated, with constricted anterior corner and with maxillary tooth row extending posteriorly to a level below its midpoint; and tall neural spines on dorsal vertebrae ( Rieppel 2000). N. Klein et al. (2022) further characterized N. mirabilis by the following postcranial features: prominent zygantrum-zygosphene articulations connecting neural spines of dorsal vertebrae; large intercentral spaces between cervical and anterior dorsal centra; humerus flat, with broad shaft; humerus with prominent edge at beginning of proximal margin of postaxial shaft and thin but broad crest forming preaxial half; ulna flat; humerus / femur ratio 1.12;, ilium without distinct offset of iliac blade; ischium symmetrical; pubis with weakly developed prepubic process and slit-like obturator foramen; and femur straight.

Comments.

As traditionally classified, Nothosaurus comprises several species in the German Triassic. However, the phylogenetic analyses by Lin et al. (2017) and Hinz et al. (2019), which also includes species from other regions, found that the genus is not monophyletic.

References.

Münster (1834), Meyer (1839, 1847–1855), Giebel (1847), F. Huene (1957), Schultze (1970), Rieppel (1993, 2000), Rieppel and Wild (1996), Lin et al. (2017), Hinz et al. (2019), N. Klein et al. (2022).

Figures

Figure 7. Reptiles from the Muschelkalk Group. A, B. Simosaurid eosauropterygian Simosaurus gaillardoti (SMNS 10360), cranium in dorsal (A) and ventral (B) view. Scale bar: 5 cm. C, D. Nothosaurid eosauropterygian Nothosaurus mirabilis (SMNS 16433), cranium in in dorsal (C) and ventral (D) view. Scale bar: 5 cm.