RECORD OF THE BOTHID FLOUNDER ASTERORHOMBUS-FIJIENSIS FROM THE WESTERN PACIFIC, WITH OBSERVATIONS ON THE USE OF THE 1ST DORSAL-FIN RAY AS ALURE

In the Indo-West Pacific bothid flounder Asterorhombus fijiensis, the first dorsal-fin ray is completely separated from the other rays and b ears a membranous distal structure resembling a small fish or crustace an, both in morphology and coloration. A live specimen, the fourth kno wn example of the species, was observed in its natural habitat and in an aquarium, and seen to repeatedly vibrate the membranous structure n ear its mouth. Although actual attraction of prey species was not obse rved, the first dorsal-fin ray and membranous structure are interprete d as an illicium and esca, structures used in aggressive mimicry for a ttracting prey. This is the only pleuronectiform species known to appa rently lure prey with a modified first dorsal-fin ray. The species is redescribed in detail and generic characters presented. Its distributi on is now known to be Fiji Islands, northern Mozambique, Western Austr alia and southern Japan. Asterorhombus fijiensis and A. intermedius ar e the only described species in the genus.