Zanclodon laevis (Plieninger, 1846)

Fernández, Omar Rafael Regalado, Stöhr, Henrik, Kästle, Benedikt & Werneburg, Ingmar, 2023, Diversity and taxonomy of the Late Triassic sauropodomorphs (Saurischia, Sauropodomorpha) stored in the Palaeontological Collection of Tübingen, Germany, historically referred to Plateosaurus, European Journal of Taxonomy 913 (1), pp. 1-88 : 61

Zanclodon laevis (Plieninger, 1846)

Smilodon laevis Plieninger, 1846a: 152 .

Zanclodon plieningeri Fraas, 1896: 18 [objective synonym].

Belodon plieningeri – Plieninger 1849 : 171; 1852: 389.

non Zanclodon crenatus Plieninger, 1846 – Fraas 1896: 18.

non Zanclodon suevicus ( Meyer, 1861) – Fraas 1896: 18.

non Zanclodon arenaceus Fraas, 1896: 18 .

Type material

Lectotype

GERMANY • a fragmentary maxilla; Swäbisch Hall , Gaildorf, Erfurt Formation of Germany (Ladinian, Middle Triassic); SMNS 6045 .

Remarks

The material collected from the Knollenmergel near Aixheim before 1850 was first referred to as Zanclodon laevis by Plieninger (1847: 207) and then as Belodon plieningeri (Plieninger 1849: 171; 1852: 389). However, Quenstedt (1885) continued to refer to the material housed in the Palaeontological Collection as Zanclodon laevis (species 8 in Fig. 3 ). Fraas (1896: 18) argued that because in palaeontology and geology, the designation by Quenstedt was so commonplace, the term Zanclodon laevis should be transferred to the material in Tübingen to designate the dinosaur material from the Knollenmergel. Fraas (1896) then erected the name Zanclodon plieningeri to refer to the fragmentary maxilla SMNS 6045. This decision was challenged by von Huene (1907: 187–190), who suggested Zanclodon laevis should be restricted only to the fragmentary maxilla SMNS 6045. For taxonomic stability, Zanclodon laevis is restricted only to the maxilla SMNS 6045, and Zanclodon plieningeri is an objective synonym of Zanclodon laevis . The material in the GPIT collection is an assortment of presumed archosaur remains removed from Zanclodon .

The species Zanclodon crenatus refers to very fragmentary teeth ( von Huene 1907: 239, figs 258–262) that Fraas (1896) identified as belonging to Belodon Meyer, 1844 . The material comes from the type locality of Zanclodon laevis (Gaildorf) . Belodon is currently considered a valid name of genus of phytosaur. Then this specific name should be removed from Zanclodon . Belodon crenatus is likely a nomen dubium.

Teratosaurus suevicus (species 28 in Fig. 3 ) was erected by von Meyer (1861) and recombined by Fraas (1896) as Zanclodon laevis to designate a large maxilla. This material is removed from Zanclodon .

Zanclodon arenaceus was erected by Fraas (1896) to identify a fragmentary lower jaw that was similar in morphology to Z. laevis . However, this identification is unsubstantiated, and the generic placement is left open, as suggested by Hungerbühler (2001).

Figures

Fig. 3. Timeline showing changes in the taxonomic placement of the specimens of early-diverging sauropodomorphs considered to be Plateosaurus Meyer, 1837 from 1900 to 2004. This timeline considers only papers discussing taxonomy and papers describing and naming new species. Lines indicate continuity or change in specimen composition of species across revisions. Arrows outside the timeline indicate that the taxa were named before 1900 and/or are still valid after 2004. When more lines depart from one node, part of the specimens included in that species were referred to as different species. Lines converging in one node indicate that the specimens were lumped together into the species in the node. Stars at the end of a line indicate that in the taxonomic revision, the name became either a nomen dubium or a nomen nudum. Lines continuing after this point indicate that the specimens were referred to the new node. This timeline does not include specimens removed from the genus Plateosaurus, namely Efraasia (von Huene, 1907–1908), Ruehleia Galton, 2001, Camelotia Galton, 1985 and Tuebingosaurus Regalado Fernández & Werneburg, 2022. The green lines correspond to species that have been synonymized withPl. trossingensisFraas, 1913, and the blue lines correspond to those that have been synonymized with Pl. gracilis(von Huene, 1905). The orange-red lines refer to species removed from Sauropodomorpha Huene, 1932 altogether. Changes after 2004 are discussed in the text.