| Family | Scientific Name | Author | Year | Common Name |
| Gonostomatidae | Sigmops elongatus | (Gunther) | 1878 | Elongate Lightfish |
Sigmops elongatus
Unique Characteristics: Photophores obvious, if not always conspicuous; ORB and OP relatively well developed, a glandular mass present below OP; OA mostly on a single level low on sides, only the 1st 1 or 2 elevated. Pterygoid teeth all small or a few posterior ones slightly enlarged. Anal fin rays 27-31. Gill rakers (10-12)+(7-9) = 18-21. IV (part of entire ventral photophore row extending from anterior end of isthmus to a vertical line at pelvic fin origin) 14-16. Body and head with numerous minute photophores (not always evident); each SO (photophore situated near anterior end or symphysis of lower jaw) and ORB surrounded by mass glandular tissue. Tail about equal to head and trunk. Interspace teeth in jaws not close-set.
Similar Species:
Sigmops bathyphilus, Spark Lightfish
Spark Lightfish, Sigmops bathyphilus. Photophores minute, obscure; ORB, OP and SO (photophore situated near anterior end or symphysis of lower jaw) usually obsolete in adults; OA irregularly arranged, some rather high on sides. A few posterior pterygoid teeth much enlarged. Anal fin rays 21-24. Gill rakers (15-17)+(9-11) = 24-28. IV (part of entire ventral photophore row extending from anterior end of isthmus to a vertical line at pelvic fin origin) 11-13.
References:
Goode, G.B. and T. H. Bean. 1896. Oceanic ichthyology. A treatise on the deep-sea and pelagic fishes of the world, based chiefly upon the collections made by the Steamers Blake, Albatross, and Fish Hawk in the northwestern Atlantic, with an atlas containing 417 figures. Special Bulletin. Smithsonian Institution. United States National Museum. Washington, DC. 927 pp.
Schaefer, S., R.K. Johnson, and J. Badcock. 1986. Gonostomatidae. In Smiths’ Sea Fishes, edited by M. M. Smith and P.C. Heemstra. Johannesburg, MacMillan, South Africa, pp. 247-253.