Infectious spondylitis with pathology mimicking that of tuberculosis in a cervical vertebra of a plesiosaur from the Upper Cretaceous of Patagonia, Argentina

TALEVI, MARIANELLA; MITIDIERI, MATÍAS; FERNÁNDEZ, MARTA

CRETACEOUS RESEARCH (PRINT)

ACADEMIC PRESS LTD-ELSEVIER SCIENCE LTD

Año: 2021 vol. 128 p. 1 - 6

0195-6671

Paleopathological studies have been used to understand the history of injury and disease in extinctpopulations, their putative causes and, on this basis, to infer paleoecology and behavioral aspects. Themost common pathologies reported in the zoological/paleontological record are traumatic injuries, posttraumaticmalformations, inflammatory arthritis, infection and congenital defects. Although pathologiesin plesiosaurs are recognized since the 1870s, reports of infectious disease are comparatively scarce. Herewe report the pathological cervical vertebra of a plesiosaur recovered from the Upper Cretaceous ofArgentina. The anterior external surface shows an elliptical, subchondral erosion with new bone formationand slight adjacent filigree reaction. The right anteroventral surface of the centrum bears erosiveprocesses with bone reaction and alterations that have the appearance produced by space-occupiedmasses. On the left anteroventral surface of the centrum, there are abnormal vascular channels, associatedwith a groove just ventral to the articular surface. The combination of these features indicates thatthe pathological aspect of the vertebra is due to an infection. The pattern of bone abnormalities iscompatible with those described in Pleistocene mammals affected by the granulomatous tuberculosisinfection and with the abnormal ribs and cervical vertebrae of an eosauropterygian from the Triassic. Thecase reported herein represents the first record of tuberculosis-like infection in a plesiosaur. As thevertebra was not part of an associated skeleton, we cannot infer if the cause of death could have beenrelated to the compromised hunting ability (due to limited neck mobility) or the result of infectionrelatedorgan failure.