J. Zool., Lond. (1988) 216, 519-528 Dentition and diet in snakes: adaptations to oophagy in the Australian elapid genus Simoselaps J. D. SCANLON 1 AND R. SHINE Zoology A08, The University of Sydney, NSW 2006, Australia (Accepted 23 February 1988) (With 2 figures in the text) Most small fossorial proteroglyphous Australian snakes of the genus Simose/aps feed on adult lizards, but the species of one lineage (the semifasciatus group) feed exclusively on the eggs of squamate reptiles. Examination of cleared, alizarin preparations showed that dentition of the saurophagous species is similar to that of other elapids, but dentition of the oophagous taxa is highly modified . The anterior (palatine and maxillary) teeth other than the fangs are reduced in size and number whereas those of the pterygoid (and in S. 'roperi', the dentary) are enlarged posteriorly, becoming compressed along a longitudinal plane and angled media lly . The shape of the pterygoid and quadrate is also modified. Two Simose/aps species with broader diets (eating both adult lizards and their eggs) show typical 'saurophagous' dentition in one case, 'oophagous' dentition in the other, showing that either type of dentition can be used to capture and ingest either type of prey. We suggest functional explanations for the dentitional modifications in the egg-eating snakes, primarily in terms of the advantages of applying considera ble force to the eggshell. Oophagous modifications within Simose/aps are convergent with those seen in several independently-derived lineages of oophagous colubrid snakes, but (perhaps because of the presence of the fang) differ in having the enlarged blade-like teeth on the pterygoid or dentary rather than the maxilla. Introduction Materials and methods Results Discussion References .. Contents Introduction Page 519 520 521 525 527 Many species of snakes feed on only one or a few types of prey, and show corresponding modifications of cranial anatomy and dentition. Distantly related taxa of snakes often show remarkable convergences in trophic morphology (e .g. Savitsky, 1983). The best-studied example of this phenomenon is the independent evolution of enlarged venom-conducting fangs in several lineages of snakes (e .g. McDowell, 1986), but even more detailed resemblances have evolved among snakes with highly specialized diets. Perhaps the best example occurs among snakes which feed mainly or exclusively on reptilian eggs. Reduction in size and number of the anterior I Present address: Department of Zoology, University of New South Wales, P.O. Box I, Kensington 519 0952-8369/ 88 / 011519+ 10 S03'00 © 1988 The Zoological Society of London