a1 39 Bow Arrow Lane, Dartford, Kent DA2 6PG, UK
The first specimen of the ankylosaur genus Polacanthus from the mainland Barremian of southeast England is described as Polacanthus rudgwickensis sp.nov. Polacanthus rudgwickensis is larger than Polacanthus foxii, and there are significant differences in the dermal armour, the tibia and caudal vertebrae of the two species. Polacanthus foxii appears to be restricted at present to the Isle of Wight with one specimen from southwest England, whilst Polacanthus rudgwickensis is only known from Sussex. This geographical distribution, the palaeobiological implications and possible sexual dimorphism are discussed for this genus.
(Received December 07 1995)
(Accepted June 24 1996)