The first snake from the lower Eocene (MP 10-11) of the Cos locality, Phosphorites du Quercy, France

Squamate faunas from the early Eocene of Europe are rare. We here describe an isolated maxilla from the early Eocene (MP 10-11) Cos locality in southwestern France. This specimen represents the only find of snake from this locality and represents the oldest described and figured cranial remain of Constrictores (i.e., the group encompassing boas and pythons) from the Cenozoic of Europe, being older than Messel, Geiseltal, Hordle, and all Quercy localities where snakes have been previously documented. The maxilla from Cos bears some resemblance with Palaeopython Rochebrune, 1880, which could then represent the oldest known occurence of this taxon. However, based on this single available element, we refer it as Constrictores indet.