Description

Dendrocystites aff. sedgwicki
Upper Ordovician (Pusgillian)
Lower Ktaoua Formation
Tizi n-Mouri, Morocco
Very large, complete 75mm carpoid on 102mm slab.

Dendrocystites is a genus of Ordovician carpoid that had been known just from North America and Europe until the recent finds in Morocco.

Carpoids appeared during the Cambrian but apparently died out in the Early Devonian. They were once considered stem-group echinoderms and allied with other groups because they lacked the radial symmetry (pentaradial in adults) of echinoderms. In fact, they lack any symmetry. The consensus seems to be that they are echinoderms who liked to keep it weird.

What is a carpoid? This article explains them (PDF)