A Paleocene vertebrate-bitten crocodilian coprolite from Liverpool Point, Maryland, U.S.A.

Although still exceedingly rare, the number of known vertebrate-bitten coprolites continues to increase. A vertebrate-bitten coprolite is herein reported from the Piscataway Member of the upper Paleocene Aquia Formation at Liverpool Point, Maryland, U.S.A. The specimen is described, figured, and chemically characterized by means of non-destructive hand-held energy dispersive X-ray fluorescence (HH-XRF). Four roughly parallel and evenly spaced gouges disrupt the surface of this compound ichnofossil. Many more much smaller markings, interpreted as feeding traces by smaller organisms (invertebrates or small actinopterygian fishes?), also ornament its surface. Whereas the studied coprolite can be identified most likely as the fossilized feces of a crocodilian, the identity of the vertebrate(s) that bit it remains unknown.