Description

Late Mississippian
Bear Gulch Limestone
Fergus County, Montana, USA
47mm shrimp on 83mm slab.

Arthropod. Crustacean. Carboniferous

Aenigmacaris is an extinct genus of crustacean.  Its closest modern relatives are mantis shrimp.  It was an enigma to researchers when it was being described as they were unsure how to classify it within the Class Malacostraca.

It appears Aenigmacaris is known from only the Bear Gulch locality and the Kinney Brick Quarry, New Mexico, both being Carboniferous-age.

Bear Gulch piece with the specimen nicely centered on matrix. Nice detail.