Published December 4, 2025 | Version v1
Taxonomic treatment Open

Psephoderma alpinum Meyer 1858

  • 1. Department of Paleobiology, National Museum of Natural History, MRC 121, Smithsonian Institution, Washington, DC 20560, USA
  • 2. Staatliches Museum für Naturkunde Stuttgart, Rosenstein 1, 70191 Stuttgart, Germany & Institut für Biologie, Universität Hohenheim, Garbenstrasse 30, 70599 Stuttgart, Germany

Description

Psephoderma alpinum Meyer, 1858

Holotype.

SNSB-BSPG AS I 8, carapace.

Type locality.

Winkelmoos Alm, southwest of Ruhpolding, Bavaria.

Type horizon.

Kössen Formation. Age: Late Triassic (late Norian-Rhaetian).

Diagnosis.

Distinguished by the following combination of features of the dermal armor: Carapace with three longitudinal ridges, one dorsomedial and two dorsolateral ones, which are composed of enlarged and distinctly keeled or tubercle-like osteoderms (Rieppel 2002 a).

Comments.

Several excellently preserved specimens from the middle to upper Norian Calcare de Zorzino in northern Italy have fully documented the skeletal structure of Psephoderma alpinum (Pinna and Nosotti 1989; Renesto and Tintori 1995; Rieppel 2001 a). Broili (1921) described a small partial cranium (SNSB-BSPG 1921 I 3) from the Kössen Formation of Kothalpe at the Wendelstein in the Bavarian Alps as “ Placochelys alpis sordidae. ” Rieppel (2000) considered it likely that this specimen can be assigned to Psephoderma but treated the binomen as a nomen dubium. Pinna (1976) and Rieppel (2000) noted that a fragment of a palate (SNSB-BSPG AS I 1457) from the Kössen Formation at the Plankensteinsattel (Tegernsee) in the Bavarian Alps, which Oswald (1930) named Placochelys stoppanii, can be referred to Psephoderma.

References.

Meyer (1858), Broili (1921), Oswald (1930), F. Huene (1936), Westphal (1975), Pinna (1976), Pinna and Nosotti (1989), Renesto and Tintori (1995), Rieppel (2000, 2001 a, 2002 a).

Notes

Published as part of Sues, Hans-Dieter & Schoch, Rainer R., 2025, Synopsis of the Triassic reptiles from Germany, pp. 411-483 in Fossil Record 28 (2) on pages 411-483, DOI: 10.3897/fr.28.164405

Files

Files (2.0 kB)

Name Size Download all
md5:dbd58c9abb51a389a8df97241d3f6b3b
2.0 kB Download

System files (15.9 kB)

Name Size Download all
md5:c9e40c143fe9463a30dd0074197b0e1e
15.9 kB Download

Linked records

Additional details

Biodiversity

Scientific name authorship
Meyer
Kingdom
Animalia
Phylum
Chordata
Order
Placodontia
Family
Placochelyidae
Genus
Psephoderma
Species
alpinum
Taxon rank
species
Taxonomic concept label
Psephoderma alpinum Meyer, 1858 sec. Sues & Schoch, 2025

References

  • Rieppel O (2002 a) The dermal armor of the cyamodontoid placodonts (Reptilia, Sauropterygia): morphology and systematic value. Fieldiana (Geology), n. s. 46: 1–41. https://doi.org/10.5962/bhl.title.3275
  • Pinna G, Nosotti S (1989) Anatomia, morfologia funzionale e paleoecologia del rettile placodonte Psephoderma alpinum Meyer, 1858. Memorie della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale di Milano 25 (2): 15–50.
  • Renesto S, Tintori A (1995) Functional morphology and mode of life of the Late Triassic placodont Psephoderma alpinum Meyer from the Calcare di Zorzino (Lombardi, N Italy). Rivista Italiana di Paleontologia e Stratigrafia 101: 37–48.
  • Rieppel O (2001 a) The cranial anatomy of Placochelys placodonta Jaekel, 1902, and a review of the Cyamodontoidea (Reptilia, Placodontia). Fieldiana (Geology), n. s. 45: 1–104. https://doi.org/10.5962/bhl.title.3449
  • Rieppel O (2000) Sauropterygia I. Placodontia, Pachypleurosauria, Nothosauroidea, Pistosauroidea. Handbuch der Paläoherpetologie Part 12 A. Verlag Dr. Friedrich Pfeil, Munich, 1–134.
  • Pinna G (1976) Placochelys zitteli, Placochelys stoppanii, Placochelyanus malanchinii: un caso de sinonimia fra i rettili placodonti retici della famiglia Placochelyidae. Bollettino della Società Palaeontologica Italiana 15: 107–110.
  • Huene F von (1936) Henodus chelyops, ein neuer Placodontier. Palaeontographica A 84: 99–148.
  • Westphal F (1975) Bauprinzipien im Plattenpanzer der Placodonten (Reptilia triadica). Paläontologische Zeitschrift 49: 97–125. https://doi.org/10.1007/BF02988070