Description

Carbosesostris megaliphagon
Annelid worm
Mississippian
Bear Gulch Limestone
Fergus County, MT  USA.

34mm (60mm if outstretched) on 87mm slab.

Soft-bodied. Lagerstatten.

Here is an marine worm that has been identified as belonging to the Phylum Annelida, aka the annelids, a group still living today and boasting around 22,000 species including earthworms and leeches. They are distinct from other worms in that they have segmented bodies. This one comes from a deposit recently discussed on the 2020 PBS documentary, “Prehistoric Road Trip.”  Bear Gulch is famous for its fishes and shelled invertebrates but it also sometimes preserves parts of the soft anatomy of those and other animals.

This specimen shows the basic form of a worm and a texture difference from the matrix. It appears it could be further prepped on the left side to reveal a little more of it. As-is, it’s an interesting piece for collectors of soft-bodied animals.