Family Myctophidae

Myctophidae

Taxonomy: Large family with more than 250 species in 33 genera; 25 genera with 99 described species in Australian waters.

Distribution, ecology and habitat: Worldwide in all oceans and seas from Arctic to Antarctic waters; most are meso- and bathypelagic by day, living at 150-2000 m and migrating vertically to feed in the upper 100 m at night, some even reaching surface waters. A few species are benthopelagic and deeper living species may not undertake vertical migrations.

Characteristics:
Body slightly compressed, elongate, eye large, diameter usually much greater than snout length; mouth large, usually terminal jaws moderate to large with bands of small, simple, closely set teeth; maxilla excluded from gape of mouth by premaxilla. Single dorsal over or in front of anal fin, pelvic fins abdominal, pectoral fins absent, or small to large, dorsal adipose fin present. and light organs or photophores arranged in groups and rows on head and body; scales usually cycloid, deciduous. Photophores and other luminous tissue present in most; conspicuous photophores in paired rows or groups on head and body, primary row on ventral surface with smaller groups between ventral row and lateral line; other luminous tissue may include secondary photophores on head and body, specialized photophores on head around eyes, luminous patches or scales at fin bases and luminous organs on caudal peduncle (often in sexually dimorphic patterns); myctophid bioluminescence is intrinsic - produced by a chemical reaction within the body cells.

Size: One species reaches 300 mm SL, although most grow to less than 125 mm SL, and one species matures at 30 mm SL.

Food and feeding: Carnivores feeding on small planktonic crustaceans, fishes and rarely pelagic molluscs; one species is known to feed on phytoplankton.

Reproduction and early life history: Oviparous with pelagic eggs and larvae which drift in the upper layers of the ocean. While the eggs are poorly known for most species, larval lanternfishes are often among the most abundant larvae in plankton samples and are well-known for many species. Eggs small, 0.7-0.9 mm in diameter, yolk segmented, oil globule large and perivitelline space moderately large. Larvae hatch at 2 mm and metamorphose, depending on the species, between 10 to 30 mm. Larval identification to genus and species is based on a large number of characters, such as head, eye, gut and body shape, fin development and meristics, photophore development and placement, and melanophore patterns.

Fisheries: Lanternfishes have an enormous biomass, comprising 65% of all mesopelagic fishes and represent a potential fishery resource; only a few species are commercially fished off South Africa and in subantarctic waters and are reduced to fishmeal and fish oil.

Remarks: Lanternfishes are the most widely distributed, diverse and abundant fishes in the deep ocean midwaters, with a huge biomass in these oceanic waters. They are the most important food source in mesopelagic waters, being preyed upon by many fishes such as tunas, dolphinfish, hakes among others, marine mammals (seals, dolphins, whales) and even seabirds, especially penguins.

Lanternfish bioluminescence along the ventral surface of the body plays a role in countershading, or camouflaging the fish from predators by breaking up its silhouette. Each species has a unique photophore pattern which may also be involved in species recognition.

Australian species:

References:

Becker, V E. & Y.N. Shcherbachev. 1990. Benthopelagic species of the families Neoscopelidae and Myctophidae from the Indian Ocean, with a description of a new species of Diaphus. Voprosy Ikhtiol. 30(5): 845-855. [In Russian. English transl. in J. Ichthyol. 30(7): 122-134.]

Hulley, P.A. 1986. Family Myctophidae, pp. 282-321, In M.M. Smith & P.C. Heemstra (eds). Smiths’ sea fishes. Macmillan, Johannesburg, South Africa.

Hulley, P.A. 1990. Myctophidae, pp. 146-178. In Gon, O. & P.C. Heemstra. Pp.Fishes of the Southern Ocean. Grahamstown : J.L.B. Smith Institute of Ichthyology, 462 pp.

Hulley, P.A. 1996. Laternfishes, pp. 127-128. In Paxton, J.R. & Eschmeyer, W.N. (eds). Encyclopedia of fishes. Academic Press.

Hulley, P.A. & G. Duhamel. 1997. Lanternfishes (Myctophidae) collected during the 1971-Pelagia cruises of R.V. "Coriolis" in the south-west Pacific Ocean. Cybium 21(3): 299-317.

Moser, H.G. & E.H. Ahlstrom. 1974. Role of larval stages in systematic investigations of marine teleosts: The Myctophidae, a case study. Fish. Bull. 72: 391-413.

Moser, H.G., & E.H. Ahlstrom. 1996. Myctophidae: Lanternfishes, p. 387-475. In H.G. Moser (ed.). The early stages of fishes in the California Current region. CalCOFI Atlas 33. Allen Press, Lawrence, Kansas, 1505 pp.

Moser, H.G., E.H. Ahlstrom & J.R. Paxton. 1984. Myctophidae: development, p. 218-244, In H.G. Moser et al., (eds). Ontogeny and systematics of fishes. Am. Soc. Ichthyol. Herpetol. Spec. Publ. No. 1

Nafpaktitis, B.G. 1978. Systematics and distribution of lanternfishes of the genera Lobianchia and Diaphus (Myctophidae) in the Indian Ocean. Los Angeles Co. Mus. Nat. Hist. Sci. Bull. 30: 1-92.

Nafpaktitis, B.G., Backus, R.H., Craddock, J.E., Haedrick, R.L., Robinson, B.H. & Karnella, C. 1977. Family Myctophidae. In Fishes of the Western North Atlantic. Sears Found. Mar. Res., Mem. No. 1, Part 7: 13-265. Yale University, New Haven, CT.

Nafpaktitis, B.G. & M. Nafpaktitis. 1969. Lanternfishes (family Myctophidae) collected during cruises 3 and 6 of the R/V Anton Bruun in the Indian Ocean. Los Angeles Co. Mus. Nat. Hist. Sci. Bull. 5: 1-79.

Nafpaktitis, B.G., D.A. Robertson & J.R Paxton. 1995. Four new species of the lanternfish genus Diaphus (Myctophidae) from the Indo-Pacific. N. Z. J. Mar. Freshwater Res. 29(3): 335-344.

Paxton, J.R. 1972. Osteology and relationships of the lanternfishes (family Myctophidae). Los Angeles Co. Mus. Nat. Hist. Sci. Bull. 13: 1-81.

Paxton, J.R. 1979. Nominal genera and species of lanternfishes (family Myctophidae). Los Angeles Co. Mus. Nat. Hist. Sci. Contrib. 322: 1-28.

Paxton, J.R. & P.A. Hulley. 1999. Families Neoscopelidae and Myctophidae, pp. 1955-1964. In Carpenter, K.E. & V.H. Niem. Species identification guide for fisheries purposes. The living marine resources of the western central Pacific. Batoid fishes, chimeras and bony fishes. Part 1 (Elopidae to Linophrynidae). FAO, Rome.

Stiassny, Melanie L.J. 1997. Myctophidae. Lanternfishes. Version 01 January 1997 (under construction). http://tolweb.org/Myctophidae/15174/1997.01.01 in The Tree of Life Web Project, http://tolweb.org/