Tricleidus – Plesiosaur Directory

Genus: Tricleidus Author: Andrews 1909 Taxon status: Valid Classification: Plesiosauria → Plesiosauroidea → Cryptoclidia → Cryptoclididae Locality: UK → Cambridgeshire → Peterborough (near) → Fletton (near) Age: Jurassic → Middle Jurassic → Callovian Horizon (rock units): Jurassic → Mid Jurassic → Callovian → Oxford Clay Formation

Etymology: -

Species: T. seeleyi Species status: Valid Referred specimens: None

Species etymology: -

Author:

Andrews 1909

Type specimen:

NHMUK R 3539, half a skeleton including the skull

Age:

Callovian, Late Jurassic

Horizon:

Oxford Clay Formation (lowermost deposits)

Type location:

Near Fletton, Peterborough, UK

Referred material:

NMW 19.96.G7, a pectoral girdle; HMG V.1800, a right humerus

Tricleidus is a cryptoclidid from the Oxford Clay Formation of the UK. The holotype specimen (NHMUK R 3539) consists of disarticulated elements including most of skull and half the postcranium, from the Kosmoceras jasoni – Peltoceras athleta zones from the lowest deposits of the Oxford Clay Formation. The type and only species of Tricleidus is T. seeleyi.

Persson (1962) erected the new species ‘Tricleidus‘ svalbardensis, but this species reallocated to Colymbosaurus (Knutsen et al. 2012a).