Nyctiphruretidae

Nyctiphruretidae is an extinct family of hallucicranian parareptiles known from the late Early to the late Middle Permian of European Russia and south-central United States.

Nyctiphruretidae was named by Efremov in 1938. The type genus is Nyctiphruretus known from several Middle Permian locations in European Russia. Michael S. Y. Lee in 1997 placed the family in the larger clade Nyctiphruretia. The order was defined to include both nyctiphruretids and nycteroleterids. However, recent cladistic analyses suggest that nycteroleterids are more closely related to the Pareiasauria instead, thus making Nyctiphruretus the only genus of its order. In 2014, MacDougall & Reisz described and named a second genus of Nyctiphruretidae, Abyssomedon, from the middle Leonardian stage of the late Early Permian of Comanche County, Oklahoma, south-central United States. It contains a single species, A. williamsi, which represents the first nyctiphruretid known from North America, and the oldest species of the family.