Ichthyolestes is a genus of archaic whale, or ancient whale, that lived during the Eocene epoch of Pakistan. Ichthyolestes is part of the Pakicetidae family, which represents the earliest and least specialized ancestors of modern day whales. It walked on four legs, but was probably bound to aquatic habitats. Ichthyolestes had about the size of a fox, reaching just 60 cm in length.
Just a singular species of Ichthyolestes is known: I. pinfoldi. Fossils have been found in river deposits of Pakistan and not marine deposits. During the Eocene epoch, Pakistan was had an arid landscape with large floodplains. Its fossils show that its bones were densely built and it was therefore not built to stay on land for a long time. It probably had these dense bones to dive for food and find its buoyancy underwater. Its behaviour would be comparable to that of an otter.
Dehm & Oettingen-Spielberg, 1958
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