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Najash

Extinct genus of snakes

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Sacral region of the holotype of the “legged snake” Najash rionegrina (specimen no.: Museo Paleontológico ‘Carlos Ameghino’ 390–398) from the early Late Cretaceous (Cenomanian/Turonian) of Argentina w
Paleoninja · CC BY-SA 4.0

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Discovery and description

Fossils of Najash were found in the terrestrial Candeleros Formation, in Rio Negro Province, Argentina. The skull and spine of Najash show primitive features that resemble other Cretaceous snakes, such as Dinilysia patagonica and Madtsoiidae. Also, several characteristics of the neck and tail of Najash and Dinilysia patagonica show how the body plan of snakes evolved from a lizard-like ancestor.

Najash had not lost its sacrum, the pelvic bone composed of several fused vertebrae, nor its pelvic girdle, which are absent in modern snakes, and in all other known fossil snakes as well. Nearly all phylogenetic analyses place Najash as an early offshoot of the snake tree, outside of all living snakes.

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Monotypic taxonTaxonomic group with only one subordinate taxonSpecies descriptionFormal description of a discovered speciesParaphylyType of taxonomic groupIUCN Red ListInventory of the global conservation status of biological speciesSubtropicsGeographic and climate zoneCommon nameName generally used for a taxon, group of taxa or organism(s)