本属は4種を含む。その内,大西洋からはヒトスジナメハダカのみが知られている(Rofen, 1966; Post 1972)。本種の和名は腹中線に沿って走る1本の管状発光体に由来する。 (藤井)
Distinctive characters:
(Genus): Body and head naked except lateral line region. Dorsal fin located around midway between pectoral fin insertion and caudal fin base. Tip of lower jaw strongly curved upward. No black spot before eye. A single luminous duct along midventral line between head and pelvic fins. Lower jaw and palatine with long, well developed teeth. No saddle-like black blotches on body. Pectoral fin small. (Species): Insertion of pelvic fin under or slightly in advance of origin of dorsal fin. Anus under or posterior to base of last dorsal ray. The anterior tip of luminous duct just behind a vertical from posterior end of upper jaw. Snout to vent length 61.6〜63.9% of SL.
Distribution:
Tropical to temperate waters of three major oceans, Gulf of Mexico, and Mediterranean Sea. Type locality-Jamaica.
Remarks:
The genus includes 4 species. Among them, only L. atlanticum is known from the Atlantic (Rofen, 1966; Post, 1972). (Fujii)