Mobulavermis adustus
Middle Cambrian
Pioche Formation – Combined Metals Member
Pioche, Lincoln County, Nevada, USA

Extremely rare 65mm x 46mm (2.5 x 1.8 inches) softbodied animal on 133mm (5.2 inch) slab plus counterpart. Easily one of the most extraordinary fossils we have ever had. This animal is a stem-group arthropod called a kerygmachelid lobopodian.

Kerygmachelids sit very near the split between lobopods and dinocaridids (Anomalocaris being the most famous dinocaridid) since they both share the strange radial mouth, swimming flaps and predatory frontal appendages. Kerygmachelia itself was originally believed to be an unusual anomalocaridid, but the view that these creatures are a sister group has become more popular. They are believed to have been active, swimming predators, capturing prey with the huge spiked appendages on the head.

This specimen, Mobulavermis, is the very first species of these creatures ever found in North America and this one is even better than the holotype making it the best example known. An extraordinary specimen.

For further reading see:
Wikipedia – Kerygmachelidae
Wikipedia – Mobulavermis