Article: Hengestites, a new genus of Gault ammonites

Hengestites applanatus gen. et sp. nov., described from the Upper Gault (Lower Cretaceous, Upper Albian) of south-east England, is a primitive member of the Placenticeratidae, a family of ammonites not previously recorded from Britain. It is a characteristic fossil of the Mortoniceras inflatum Zone (Callihoplites auritus Subzone) but has hitherto escaped notice owing to homoeomorphy with Anahoplites planus (Mantell). Its occurrence points to a polyphyletic origin for the Placenticeratidae.