Rhamphocephalus

Rhamphocephalus ("beak head") is an extinct genus of fossil reptile from the Middle Jurassic (Bathonian stage) Cotswold Slate Formation of Gloucestershire, England. The name was erected as a genus of pterosaur and became a 'wastebasket taxon' for British Jurassic pterosaur remains until a recent revision. Rhamphocephalus comprises several named species, two of which are pterosaurian, but the type species - R. prestwichi - is based on remains now identified as a thalattosuchian. Because it is poorly preserved and lacks features that distinguish it from other thalattosuchians, R. prestwichi is considered an invalid species and the genus Rhamphocephalus is a nomen dubium. Reassessments of other Rhamphocephalus species suggest they are also undiagnostic to species level, although they have properties allowing referral to some Jurassic pterosaur groups.

== Discovery and naming == The holotype, OUM J.28266, is a fragment from the skull roof and it was discovered by Professor Prestwich no earlier than June 1879 in the Cotswold Slate Formation at Kineton Thorns Quarry, Stow-On-Wold, Gloucestershire. Harry Seeley obtained the holotype from Prestwich and in 1880 named Rhamphocephalus prestwichi as a pterosaur, and O'Sullivan & Martill (2018) found that only OUM J.28266 was referable to R. prestwichi due to the holotype being reclassified within Thalattosuchia.