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The anatomy and relationships of Haasiophis terrasanctus, a fossil snake by well-developed hind limbs from the Mid-Cretaceous of the Middle East

Published online by Cambridge University Press:  20 May 2016

Olivier Rieppel
Department of Geology, The Field Museum, 1400 S. Lake Shore Drive, Chicago, Illinois 60605-2496,
Hussam Zaher
Universidade de Sao Paulo, Instituto de Biociencias, Departamento de Zoologia, Rua do Matao, Travessa 14, Cidade Universitaria, 05508-900 Sao Paulo, SP, Brazil,
Eitan Tchernov
Dept. of Evolution, Systematics and Ecology, Hebrew University, Berman-Lubin Buildings, Givat Ram, Jerusalem 91904, Israel,
Michael J. Polcyn
Shuler Museum of Paleontology, Southern Methodist University, Dallas, Texas 75275,


The fossil snake species Haasiophis terrasanctus Tchernov, Rieppel, Zaher, Polcyn, and Jacobs, 2000, from the early Upper Cretaceous of the Middle East, is described and illustrated, following a review of the current debate on snake relationships and origins. The description and discussion presented here adds important detail to the knowledge of this taxon and its phylogenetic significance beyond the limited account presented in the original description of Haasiophis. The species is remarkable in that it shows the skull of a relatively advanced (i.e., macrostomatan) snake, yet preserves well-developed hind limbs. The hind limb includes a femur, tibia, fibula, astragalus, calcaneum, distal tarsal four, and remains of four metatarsals and two phalanges. Haasiophis cannot be considered a juvenile specimen of Pachyrhachis. The implications of the presence of well-developed hind limbs in Haasiophis, Pachyrhachis, and Podophis for the cladistic analysis of the phylogenetic interrelationships of these fossil snakes is discussed. The presence of well-developed hind limbs in Pachyrhachis and Haasiophis also creates methodological problems for the cladistic analysis of the phylogenetic relationships of these fossil snakes. Scenarios of snake origins are reviewed and found to be deficient in the absence of a well-corroborated hypothesis of snake relationships within Squamata.

Research Article
Copyright © The Paleontological Society

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