A possible case of necrotizing dermatitis in the crocodylian Diplocynodon, from the Oligocene of the Isle of Wight, United Kingdom

Abstract

Here we describe a pathological osteoderm from the crocodylomorph Diplocynodon hantoniensis (Bouldnor Formation, earliest Oligocene, Isle of Wight, United Kingdom). The specimen bears a porous, erosive branching channel that distorts the surface ornamentation and periosteum over 60% of the preserved dorsal surface area. We diagnose this condition as necrotizing dermatitis: a surficial bacterial or fungal infection that can penetrate the dermal layers to affect the underlaying penosteum of osteoderms. This condition has been previously reported for an extant tortoise and caiman; however, this is the first reported occurrence in the fossil record.

Keywords:

• Palaeopathology
• necrotizing dermatitis
• Diplocynodon
• crocodylian
• osteoderm

Acknowledgements

Thanks to Dr. Jerry Hooker and Sandra Chapman of the British Museum of Natural History for access to specimens. Thanks to Drs. David J. Varricchio, Elizabeth Rega, Marc Mattix DVM ACVP (Col. US Army) for previous guidance. Thanks also to Mick Green, Keith Simmons, and other members of the Isle of Wight team, as well as Warwick Fowler for constant ferrying of D. Fowler to outcrop. Thanks also, Dick Hilton of Sierra College and Rich Rust of University of Nevada, Reno; and to Elizabeth Freedman, Robert Kambic and Eric Williams for their input and to Meredith Wolff and Gina Sorrentino for their moral support. This paper is dedicated to the memory of Dr. David Cooper whose friendship and palaeopathological expertise are sorely missed by those of us who knew him.

Notes

^† [email protected]

^‡ Tel: [phone] 579 9968. [email protected]

Additional information

Notes on contributors

D. W. Fowler

† † [email protected]

J. W. Bonde

‡ ‡ Tel: [phone] 579 9968. [email protected]