(Family and Genus):A dorsal fin locates post median, without spine. No adipose fin. Anal fin base long, with one spine. Scales deciduous. Pelvic fin locates anterior to pectoral fin. Monotypic family. (Species):Anal fin rays lass than 30. Body depth at anus less than head length.
Distribution:
Western central Atlantic in deep water.
Remarks:
Six species have been known. The present species is the only species having less than 30 anal rays (Dick, 1972). (Shimizu)