ABSTRACT
The oarfish, Regalecus glesne, is the longest of all bony fishes, attaining lengths of 8-10 m. There are unconfirmed reports of some specimens reaching 17 m. The species is spectacular with brilliant red fins, a long slender body, long pelvic fins and a cocks-comb like plume of elongate anterior dorsal rays. Its tendency to appear at the sea surface after storms and its bizarre appearance are the likely source of historical accounts of sea monsters. Recent observations of live oarfish by divers confirm that the natural body position is vertical with the head up, and that the species swims using undulations of its long dorsal fin (Olney 2003). The elongate pelvic-fin ray bears a large red swelling at its tip and possesses sensory capability (Oelschläger 1983). R. glesne is rarely observed in the Atlantic Ocean but is widely distributed, occupying epi-and mesopelagic habitats. Most authors consider the genus to be monotypic. Only one species is treated here although there are several nominal forms that may be valid including one newly described species from the eastern Pacific (Castro-Aguirre et. al. 1991). Another regalecid, Agrostichthys parkeri, is also rare, occurring in the southern ocean and apparently capable of delivering an electric shock (McDowall & Stewart 1997).
