Aegirocassis: The Baleen Whale of Early Ordovician

Aegirocassis from Ordovician, Procreate, 2023
Aegirocassis from Ordovician, Procreate, 2023
Aegirocassis_Sketch, Procreate , 2023
Aegirocassis_Sketch, Procreate , 2023

Aegirocassis, a giant filter-feeding arthropod that lived during the early Ordovician period (around 480 million years ago). It's a relic from the Radiodonta order, which dominated during the preceding Cambrian period.

It was large for its time, measuring nearly 2 meters long, especially since most animals of that era were smaller. It specialized in filter-feeding similar to the modern Baleen whale.

No living creatures from this order exist today.

Here is a detailed illustration and an earlier sketch.