Family CETOMIMIDAE


Common name: Whalefishes

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Summary:
Whalefish life stages are so remarkably different, that they were previously not only placed in different families, but the males were placed in a different order. Johnson et al. (2009) used morphology and mitogenomic sequences to show that fishes previously placed the Mirapinnidae (hairy fishes, tape tails) and the Megalomycteridae (bignose fishes) are actually the larvae and males of the family Cetomimidae (whalefishes). Males undergo amazing morphological and physiological changes as they mature. Juvenile males feed on copious amounts of copepods and develop enormous livers to sustain them throughout their adult life. Unlike the females which have huge mouths to catch large prey, males cannot feed because they lose their stomach and oesophagus as they mature.

Whalefishes lack external scales and the pelvic fins are absent in females, usually absent in males and jugular in position in juveniles.

Cite this page as:
Dianne J. Bray, Whalefishes, CETOMIMIDAE in Fishes of Australia, accessed 08 Dec 2019, http://fishesofaustralia.net.au/Home/family/220

More Info


Family Taxonomy

A family of deep-sea fishes with about 9 genera and more than 45 species, many of which are undescribed.

Family Description

Larvae: Epipelagic. Some species have small mouths, hair-like growths on the body, very large pelvic and caudal fins. Others have an amazingly long caudal streamer that may resemble siphonophores or even look like a sea snake. Females: Mesopelagic fishes with huge mouths, tiny eyes, and a huge lateral line canal. The dorsal and anal fins are far back on the body, the pectoral fins are small, and they lack fin spines, pelvic fins, ribs and visible scales. Males: Nasal organs very well-developed, teeth, oesophagus and stomach absent.

Family Feeding

Larval whalefishes feed on tiny crustaceans (copepods).

Family Conservation

Not evaluated.

Author

Dianne J. Bray

References


Bekker, V.E. 1981. The first find of a rare bathypelagic fish from the genus Ataxolepis (Megalomycteridae) in the southern hemisphere. J. Ichthyol. 21(3): 125-128.

Bertelsen, E. & Marshall, N.B. 1956. The Miripinnati, a new order of teleost fishes. Dana Reports 42: 1-34 figs 1-15 pl. 1

Bertelsen, E. & Marshall, N.B. 1984. Mirapinnatoidei: development and relationships. 380-383 figs 202-203 in Moser, H.G. et al. (eds). Ontogeny and Systematics of Fishes. American Society of Ichthyologists and Herpetologists. Special Publication 1: 1-760

Charter, S.R. & H.G. Moser. 1996. Mirapinnidae: ribbontails. p. 713-715. In H.G. Moser (ed.) The early stages of fishes in the California Current region. California Cooperative Oceanic Fisheries Investigations (CalCOFI) Atlas No. 33. 1505 pp.

Johnson, G.D., Paxton J.R., Sutton T.T., Satoh T.P., Sado T., Nishida M., et al. 2009. Deep-sea mystery solved: astonishing larval transformations and extreme sexual dimorphism unite three fish families. Biology Letters 5(2): 235–239.

Maul, G.E. 1969. On the genus Cetomimus (Cetomimidae) with the description of a new species. Bocagiana 18: 1-12.

Miya, M., Takeshima, H., Endo, H., Ishiguro, N.B., Inoue, J.G., Mukai, T., Satoh, T.P., Yamaguchi, M., Kawaguchi, A., Mabuchi, K., Shirai, S.M. & Nishida, M. 2003. Major patterns of higher teleostean phylogenies: a new perspective based on 100 complete mitochondrial DNA sequences. Molecular Phylogenetics and Evolution 26: 121-138.

Myers, G.S. & W.C. Freihofer. 1966. Megalomycteridae, a previously unrecognized family of deep-sea cetomimiform fishes based on two new genera from the North Atlantic. Stanford Ichthyol. Bull. 8(3): 193-207.

Nelson, J.S. 2006. Fishes of the World. 4th Edn. New Jersey : John Wiley & Sons 601 pp.

Paxton, J.R. 1989. Synopsis of the whalefishes (family Cetomimidae) with descriptions of four new genera. Records of the Australian Museum 41: 135-206

Paxton, J.R. 1990. Whalefishes: little fish with big mouths. Australian Natural History 23(5): 378-385

Paxton, J.R. 1999. Families Gibberichthyidae, Rondeletiidae, Barbourisiidae, Cetomimidae, Mirapinnidae, Megalomycteridae, Anoplogastridae, Diretmidae. pp. 2203-2211 in Carpenter, K.E. & Niem, T.H. (eds). The Living Marine Resources of the Western Central Pacific. FAO Species Identification Guide for Fisheries Purposes. Rome : FAO Vol. 4 2069-2790 pp.

Paxton, J.R. 2003. Families Barbourisiidae, Cetomimidae, Mirapinnidae. pp. 1170-1175 in Carpenter, K.E. (ed.). The Living Marine Resources of the Western Central Atlantic. Rome : FAO & American Society of Ichthyologists & Herpetologists Vol. 2 602-1373 pp.

Paxton, J.R. & D.J. Bray 1986. Cetomimidae. p. 433-434. In M.M. Smith and P.C. Heemstra (eds). Smiths' sea fishes. Springer-Verlag, Berlin.

Paxton, J.R. & O. Gon 1990. Cetomimidae. p. 222-225. In O. Gon & P.C. Heemstra (eds). Fishes of the Southern Ocean. J.L.B. Smith Institute of Ichthyology, Grahamstown, South Africa.

Paxton, J.R. & Johnson, G.D. 2003. If tapetails and the hairyfish (Mirapinnidae) are larval whalefishes (Cetomimidae), bignose/mosaic-scale fishes (Megalomycteridae) should be male whalefishes. Abstr. Ann. Meet. Am. Soc. Ichthyol. Herpetol. 2003. 371 pp.

Richardson, L.R. & J.A.F. Garrick. 1964. A new species of Gyrinomimus (Pisces, Cetomimidae) from New Zealand. Copeia 1964(3): 523-525.