Dinocarida

Dinocaridida is a proposed taxon of extinct fossil arthropod-like marine animals found, with one exception, in the Cambrian and Ordovician. It is subdivided into the anomalocaridids and the opabiniids. The name of this group comes from Greek, "deinos" and "caris", meaning "terror shrimp" or "terror crab", due to their crustacean-like appearance and the hypotheses suggesting that members of this class were amongst the dominating and most diverse apex predators of their time.