An istiodactylid pterosaur from the Upper Cretaceous Nanaimo Group, Hornby Island, British Columbia, Canada

Abstract

An unusual jaw found in a calcite nodule from Collishaw Point, Hornby Island, British Columbia (off the east coast of Vancouver Island) represents the first definitive pterosaur found in British Columbia, and the first istiodactylid from Canada. The nodule was derived from the Northumberland Formation (Nanaimo Group), a fossiliferous formation known for producing numerous plants, invertebrates, sharks, and mosasaurs. The pterosaur is represented by the anterior portion of the rostrum, including the anterior edge of the nasoantorbital fenestra, and numerous small, triangular teeth lacking denticles. These teeth are similar in overall morphology to the teeth of istiodactylids, but are smaller, more numerous, more tightly packed, and have proportionately smaller crowns. Although fragmentary, this specimen is diagnostic and represents a new genus of istiodactylid pterosaur. Its presence in the upper Campanian Northumberland Formation makes this the latest occurring istiodactylid and extends the stratigraphic and geographic range of this enigmatic group of pterosaurs.