''Prosalirus'' is the name given to a fossilised prehistoric frog found in the

Kayenta Formation The Kayenta Formation is a geological formation in the Glen Canyon Group that is spread across the Colorado Plateau province of the United States, including northern Arizona, northwest Colorado, Nevada, and Utah. Traditionally has been suggested ...

Arizona Arizona ( ; nv, Hoozdo Hahoodzo ; ood, Alĭ ṣonak ) is a state in the Southwestern United States. It is the 6th largest and the 14th most populous of the 50 states. Its capital and largest city is Phoenix. Arizona is part of the Fou ...

in 1981 by Farish Jenkins.''Geographica''; "Jurassic Frog hops into the record book", National Geographic; August 1996, pg.5. The type, and currently only, species is ''Prosalirus bitis''.

Description

The skeleton has primitive features, but has mostly lost the salamander-like traits of its ancestors. It has a skeleton designed to absorb the force of jumping with its hind legs and tail. It also has long hip bones, long hind leg bones, and long ankle bones, all similar to modern frogs, and is as of 2009 the earliest true frog. The name comes from the Latin verb prosalire, meaning 'to leap forward'. It is thought to have lived during the

Early Jurassic The Early Jurassic Epoch (geology), Epoch (in chronostratigraphy corresponding to the Lower Jurassic series (stratigraphy), Series) is the earliest of three epochs of the Jurassic Period. The Early Jurassic starts immediately after the Triassic-J ...

epoch 190 million years ago, well before the first known modern frog, '' Callobatrachus''. As of 2020, only three ''Prosalirus'' skeletons have been discovered.

References

{{Taxonbar, from=Q2117594 Early Jurassic amphibians Jurassic amphibians of North America Early Jurassic animals of North America Jurassic Arizona Paleontology in Arizona Transitional fossils Prehistoric tetrapod genera Fossil taxa described in 1995 Early Jurassic genus first appearances Early Jurassic extinctions