Saniwa ensidens, fossil
English: Fossil of Saniwa ensidens in the Field Museum of Natural History.
Date 24 August 2011
Author Smokeybjb https://commons.wikimedia.org/wiki/User:Smokeybjb
Saniwa is an extinct genus of monitor lizards that lived during the Eocene epoch around 48 million years ago. Well-preserved fossils have been found in the Bridger and Green River Formations of Wyoming, and evidence indicates Saniwa also lived in Europe. The type species S. ensidens was named in 1870 as the first fossil lizard known from North America. Several other species have since been added, but their validity is uncertain. It is a close relative of Varanus, the genus that includes extant monitor lizards. Order: Squamata, Family: Varanidae, Species: Saniwa ensidens Leidy, 1870 (type), Saniwa orsmaelensis Dollo, 1923, Synonyms: Thinosaurus Marsh, 1872