Description

Aegirocassis benmoulai Van Roy 2015
Ordovician
Lower Fezouata Formation
Eastern flank of Jbel Tigzigzaouine, facing Oued Ezegzaou, Morocco.
124mm appendage on 124mm slab. Rare example of one of the largest arthropods of all time.

Soft-bodied. Arthropod.

Aegirocassis is a genus of anomalocaridid that was one of the largest of all arthropods that have ever lived, reaching about 6 1/2 feet long and was almost certainly the largest animal of its time.  Like the largest animal of our time, the blue whale, it has been determined to have been a filter-feeder that descended from predatory ancestors.

So far, Aegirocassis is known only from the Early Ordovician of Morocco but least one other anomalocaridid survived into the Early Devonian.

Have a look at this amazing 3D model of Aegirocassis courtesy of Google and darwinmuseum.ru. Click on the arrows at the bottom right corner to see it full screen!