Lophochelys sp.

Robert & Weems, E., 2014, Paleogene chelonians from Maryland and Virginia, PaleoBios 31 (1), pp. 1-32 : 17-18

? Lophochelys sp.

( Figs. 12A–C)

Specimen —USNM 537787, associated right hyoplastron and hypoplastron found by Dave Bohaska.

Locality, horizon, and age — Hill behind Hampton Mall located near the intersection of Central Avenue and Interstate 95, Prince Georges County, Maryland; Brightseat Formation; early Paleocene (Danian) .

during the Late Cretaceous ( Zangerl 1953), but they were decimated during the end-Cretaceous extinction event. Wood (1973) documented the persistence of one member of this group into the Paleocene of west-central Africa, part of a plastron too incomplete to assign to a genus. Moody (1980) has suggested that the early Eocene London Clay turtle Neurochelys harvicensis ( Woodward 1830) also may belong to this group, but this conclusion has not been subsequently followed ( Lapparent de Broin 2001).

The associated hyoplastron and hypoplastron described here constitute the first record of this group in the Paleogene of the Atlantic Coastal Plain. The lack of elongation in the distal part of the hyoplastron and hypoplastron is typical of juvenile primitive pancheloniids ( Nicholls 1988); this characteristic and the very small size of these elements both suggest that this material represents an immature individual. It is likely that this specimen pertains to Lophochelys , which was a persistently small Late Cretaceous North American form, but the partial plastron described here is too incomplete to be certain of this so assignment to this genus is queried.