👉 Eumicrus is a genus of extinct marsupials that lived during the Cretaceous period, approximately 68-64 million years ago. They were characterized by their large, flattened, and elongated bodies, which allowed them to swim efficiently in water, despite being small in size. Eumicrustids are known for their unique, highly developed brains with specialized neural networks that allowed them to think and reason effectively during their life span.