Most animals and plants never fossilize. For those that do, it’s usually only hard parts such as bones and shells that preserve. However, in some exceptional cases, soft tissues such as muscles and gills survive the fossilization process and can present a wealth of information about the biology and ecology of ancient organisms.

In a paper recently published in Palaeontologia Electronica, Dr. Adiel Klompmaker, University of Alabama Museums’ curator of paleontology, and colleagues reported on a remarkable crab with multiple mineralized soft tissues preserved. This crab lived 75 million years ago during the Cretaceous in the area of present-day South Dakota in an ancient sea known as the Western Interior Seaway.