Description

Cheloniellid
Ordovician
Fezouata Formation
Mecissi-Zagora Region, Draa Valley, Morocco.

Huge 155mm (6 inch) cheloniellid arthropod on 320mm (12.6 inch) slab.

Arthropod.

A cheloniellid is an extinct invertebrate of uncertain classification among arthropods. The Cheloniellida has been considered a taxonomic class by some researchers while others deem it to be an order. In any case the group, members of which looked like flattened pill bugs, appears to be closely related to trilobites and chelicerates (arachnids, eurypterids, arachnids).

Cheloniellids are known from the Late Cambrian to Devonian at sites in North America, Europe, and North Africa.