Biology:Infratemporal fenestra

Short description: Opening in the skull behind the orbit in some animals

The lateral temporal fenestra in relation to the other skull openings in the dinosaur Massospondylus.

A human, synapsid, skull. Note the presence of only one infratemporal fenestra.

An infratemporal fenestra, also called the lateral temporal fenestra or simply temporal fenestra, is an opening in the skull behind the orbit in some animals. An opening in front of the eye sockets, conversely, is called an antorbital fenestra. Both of these openings reduced the weight of the skull. Infratemporal fenestrae are commonly (although not universally) seen in the fossilized skulls of dinosaurs. Synapsids, including mammals, have one temporal fenestra, while sauropsids, the birds and reptiles, have two.