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Early Eocene lagomorph (Mammalia) from Western India and the early diversification of Lagomorpha.

ABSTRACT: We report the oldest known record of Lagomorpha, based on distinctive, small ankle bones (calcaneus and talus) from Early Eocene deposits (Middle Ypresian equivalent, ca 53 Myr ago) of Gujarat, west-central India. The fossils predate the oldest previously known crown lagomorphs by several million years and extend the record of lagomorphs on the Indian subcontinent by 35 Myr. The bones show a mosaic of derived cursorial adaptations found in gracile Leporidae (rabbits and hares) and primitive traits characteristic of extant Ochotonidae (pikas) and more robust leporids. Together with gracile and robust calcanei from the Middle Eocene of Shanghuang, China, also reported here, the Indian fossils suggest that diversification within crown Lagomorpha and possibly divergence of the family Leporidae were already underway in the Early Eocene.

SUBMITTER: Rose KD

PROVIDER: S-EPMC2602686 | biostudies-literature | 2008 May

REPOSITORIES: biostudies-literature

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Early Eocene lagomorph (Mammalia) from Western India and the early diversification of Lagomorpha.

Rose Kenneth D KD DeLeon Valerie Burke VB Missiaen Pieter P Rana R S RS Sahni Ashok A Singh Lachham L Smith Thierry T

Proceedings. Biological sciences 20080501 1639

We report the oldest known record of Lagomorpha, based on distinctive, small ankle bones (calcaneus and talus) from Early Eocene deposits (Middle Ypresian equivalent, ca 53 Myr ago) of Gujarat, west-central India. The fossils predate the oldest previously known crown lagomorphs by several million years and extend the record of lagomorphs on the Indian subcontinent by 35 Myr. The bones show a mosaic of derived cursorial adaptations found in gracile Leporidae (rabbits and hares) and primitive trai ...[more]

PMID: 18285282

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Early Eocene lagomorph (Mammalia) from Western India and the early diversification of Lagomorpha.

Publications

Early Eocene lagomorph (Mammalia) from Western India and the early diversification of Lagomorpha.

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