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Updated: Jul 17, 2026

Computer-Generated Animal Model Stimuli
Published on: July 29, 2007
A fossil snake with limbs
E Tchernov1, O Rieppel, H Zaher
1Department of Evolution, Systematics, and Ecology, Hebrew University of Jerusalem, Berman-Lubin Buildings, Givat Ram, Jerusalem 91904, Israel.
Abstract:
A 95-million-year-old fossil snake from the Middle East documents the most extreme hindlimb development of any known member of that group, as it preserves the tibia, fibula, tarsals, metatarsals, and phalanges. It is more complete than Pachyrhachis, a second fossil snake with hindlimbs that was recently portrayed to be basal to all other snakes. Phylogenetic analysis of the relationships of the new taxon, as well as reanalysis of Pachyrhachis, shows both to be related to macrostomatans, a group that includes relatively advanced snakes such as pythons, boas, and colubroids to the exclusion of more primitive snakes such as blindsnakes and pipesnakes.
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