Osteomyelitis in a 265-million-year-old titanosuchid (Dinocephalia, Therapsida)

Abstract

Analytical palaeohistology techniques have allowed a better understanding of the microstructure of fossil bone, as well as of bone pathologies of extinct animals. Osteomyelitis is one of the oldest identified bone pathologies, occurring in Synapsida dating back as far as the Lower Permian. Here we show the presence of this pathology in the femur of Jonkeria parva, an omnivorous titanosuchid from the Tapinocephalus Assemblage Zone of the Karoo Basin of South Africa. The pathology is characterised by bony radial spicules growing perpendicular to the normal orientation of the unaffected fibrolamellar bone tissue, and shows localised increase in vascular canal size. Puncture marks on the femur suggests that an attack by a predator may have resulted in a bacterial infection that caused contiguous and subjacent osteomyelitis.

Keywords:

• Permian
• Synapsida
• therapsid
• histology
• palaeopathology

Acknowledgements

Roger Smith and Zaituna Erasmus of the Iziko SA Museum in Cape Town, South Africa are thanked for access to the Jonkeria specimen (SAM-PK-12233). Sifelani Jirah of the University of Witwatersrand in Johannesburg, South Africa is thanked for lending his expertise to the taxonomic identification of SAM-PK-12233, and for sharing his as yet unpublished PhD research on the Titanosuchidae. Michael Shipley of Midwestern State University in Wichita Falls, TX, USA is thanked for providing insight and discussion about osteomyelitis. Permit 2076 (for histological analyses) was provided by the South African Heritage Resources Agency (SAHRA).