On the presence of Bufo nasicus Werner in Guiana, with a redescription of the species on the basis of recently collected material

During research on material recently collected in Guyana and in Venezuelan Guiana, several specimens of the rare toad Bufo nasicus Werner, thus far only known from the holotype without known origin, were discovered. On the basis of this material the species is redescribed and some notes on its natural history are given. The species is a member of the Bufo typhonius-group.