SilesianTriassic

Ichthyosauria indet. (cf. Mixosauridae)

Middle Triassic, Lower Gogolin Beds, Upper Silesia, Poland

A vertebral centrum of a small marine reptile, likely a member of the Mixosauridae—early ichthyosaurs known from the Triassic.

The centrum is short, disc-shaped, subhexagonal in outline, and tapering upward. The articular surfaces of the centrum are strongly amphicoelous. Dorsally, the floor of the neural canal is clearly visible. A faint chevron groove is visible ventrally.

Ventrolaterally, chevron facets are preserved (see photo 2, photo 3).

The morphology of the centrum—specifically its disc-shaped, subhexagonal form—is consistent with ichthyosaur centra in the literature. The small size of the centrum and its overall morphology, combined with its stratigraphic position (Anisian), strongly suggest a member of the Mixosauridae. Additionally, the chevron facets and the presence of the ventral groove indicate a caudal vertebral centrum, while its considerable width suggests an anterior caudal vertebra

References:

• John C. Merriam. (1908). Triassic Ichthyosauria: With special reference to the American forms.

Changes:

• 2026-08-24 – Identification Ichthyosauria indet. (cf. Mixosaurus) downgraded to Ichthyosauria indet. (cf. Mixosauridae)