A new species of the blind goby Caecogobius (Gobioidei, Gobiidae, Gobionellinae) from a cave system on Mindanao Island, the Philippines

Abstract

A new species of the eyeless goby genus Caecogobius is described from a cave system on Mindanao Island, the Philippines. Caecogobius personatus sp. nov. is the second cave-obligate fish ever discovered from the Philippine archipelago. The first species, Caecogobius cryptophthalmus Berti and Ercolini 1991 was recorded from Samar Island, an adjacent island north of Mindanao. The new species differs from its only congener, C. cryptophthalmus, in having a finely ridged fleshy area over the orbit and fleshy flap-like sensory papillae on fleshy raised ridges (the sensory papillae in C. cryptophthalmus are all small and evenly sized, not fleshy or flap-like) and having all elements of the second dorsal fin segmented (first element unsegmented in C. cryptophthalmus). The relationship of these two Caecogobius to each other and to other gobionellines is not known.