Westrichus

Westrichus Temporal range: Asselian
A fossil of Westrichus
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	†Acanthodii
Order:	†Acanthodiformes
Family:	†Acanthodidae
Genus:	†Westrichus Heidtke, 2003
Type species
Westrichus kraetschmeri Heidtke, 2003
Species
W. kraetschmeri W. tholeyi (Heidtke, 1990)

Westrichus is an extinct acanthodian which lived in the Lower Permian of Germany. It contains two species: the type species, Westrichus kraetschmeri, and Westrichus tholeyi, the latter of which was previously assigned to Acanthodes.

Description

This animal was very similar to the genus Acanthodes, however it was equipped with an extremely elongated pelvic fin; it started behind the head and ended just before the retracted anal fin. The appearance, compared to that of Acanthodes, was therefore much more massive, however, the head was smaller. It had length up to 75 centimetres (30 in), and like all acanthodians, Westrichus had large spines on its fins. The dorsal fin was small and pointed backward, and was located near the larger and elongated anal fin.

Classification

First described in 2003 on the basis of fossils found in the Meisenheim Formation, Westrichus is considered a very specialised acanthodian. Like many derived representatives of the group, Westrichus had a low number of fins. It is considered a close relative of the genus Acanthodes, in the family Acanthodidae.

Palaeobiology

Westrichus fed on small crustaceans, and occasionally small fish, amphibians and even members of its own species.