Re-description and taxonomy of Pentanchus profundicolus Smith & Radcliffe,based on a second specimen from the Philippines (Chondrichthyes, Carcharhiniformes, Scyliorhinidae)

Pentanchus profundicolus is an enigmatic shark. characterized by a single d orsal fin. The holotype, which was collected in 1909 from the Philippines. had remained the only known example of the species for 90 years. A second s pecimen, collected from the same waters, is re-described. The presence of a single dorsal fin remains equivocal in so far as it represents the normal condition for the species. Aspects of the species' relationship with the sp ecies of Apristurus are discussed.