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Life restoration of Labidosaurus

Labidosaurus was an anapsid reptile from the Permian of Texas.


Labidosaurus closely resembled a heavily built lizard with a large head. It was about 75 centimeters long from the tip of the head to the tip of the tail.


Cast of a Labidosaurus skeleton

Described by Edward Drinker Cope in 1895[1], Labidosaurus hamatus is the only species in the genus. It is part of the captorhinid family of reptiles, and was one of the largest examples of the family.



The shape of Labidosaurus's teeth suggest that it was likely omnivorous. Its several rows of conical teeth would have been well-adapted to crush the shells of molluscs.[2]

Evidence of infection[]

In 2011, a lower jaw of Labidosaurus was described that showed evidence of an infection called osteomyelitis.[3] This condition affects bone and is caused by microorganisms such as bacteria. In this specimen, the pulp cavity of a broken tooth was exposed to infectious bacteria, and later developed the infection. This is the earliest known case of infection in a land-dwelling vertebrate. Osteomyelitis has also been discovered in the bones of the dinosaur Allosaurus.[4]


  2. Palmer, D., ed (1999). The Marshall Illustrated Encyclopedia of Dinosaurs and Prehistoric Animals. London: Marshall Editions. p. 63. ISBN 1-84028-152-9.
  3. Reisz, R.R.; Scott, D.M.; Pynn, B.R.; and Modesto, S.P. (2011). "Osteomyelitis in a Paleozoic reptile: ancient evidence for bacterial infection and its evolutionary significance". Naturwissenschaften 98 (6): 551–555. doi:10.1007/s00114-011-0792-1.
  4. Molnar, R. E., 2001, Theropod paleopathology: a literature survey: In: Mesozoic Vertebrate Life, edited by Tanke, D. H., and Carpenter, K., Indiana University Press, p. 337-363.