Family ENOPLOTEUTHIDAE Pfeffer, 1900
Compiler and date details
C.C. Lu, National Chung Hsing University, Taichung, Taiwan
- ENOPLOTEUTHIDAE Pfeffer, 1900.
Type genus:
Enoploteuthis d'Orbigny, 1842.Secondary source:
Pfeffer, G. 1900. Synopsis der Oegopsiden Cephalopoden. Jahrbuch der Hamburgischen Wissenschaftlichen Anstalten 17: 145-198.
Introduction
The family Enoploteuthidae Pfeffer, 1900 is a diverse group of small to medium-sized (generally less than 150 mm mantle length (ML)), mesopelagic squid. The family was traditionally considered to comprise three subfamilies: Enoploteuthinae, Ancistrocheiriinae, and Pyroteuthinae, distinguished by the distribution of photophores on the body. The latter two subfamilies were elevated to familial rank by Clarke (1988).
Worldwide about 40 species in four genera are recognised. Eleven species, in three genera, have been reported from Australia. The first enoploteuthid recorded in Australian waters, Enoploteuthis galaxias, was described by Berry (1918) from material collected during the trawling investigations of the F.I.S. Endeavour in Bass Strait. Larvae of three additional species were described by Allan (1945) from the New South Wales coast, and Nesis (1979) provided an overview of the zoogeography of the common oceanic representatives of this family in the Australasian region (including those in Ancistrocheiriinae and Pyroteuthinae).
The numerous photophores externally on the mantle, arms and tentacles are conspicuous. These structures may provide concealment from potential predators through counter-illumination, i.e. the obliteration of the animal's silhouette through bioluminescence from below (Young 1977, 1983).
Enoploteuthid reproductive organs are typically oegopsid, except that nidamental glands are absent and the oviducal glands are strongly developed. Hectocotylisation in males varies considerably between species. In mature males, enlarged protective membranes are evident distally on the edges of the hook-bearing surface of the ventral arms. Spermatophores are transferred to the nuchal crest region of females in some species, but no structures for their storage have been described ( Roper et al. 1969; Riddell 1982).
No comprehensive studies of enoploteuthid life history have been undertaken in Australian waters. While most squids spawn eggs in masses, female enoploteuthids spawn individual eggs into the plankton. Around Hawaii, eggs and larvae of enoploteuthids closely related to species in Australian waters are common in near-surface waters, although spawning locations are unknown (Young & Harman 1986). Preliminary studies provide some indication of reproductive patterns in Australasian waters. Brandt (1983) found multimodal size distributions for Abraliopsis gilchristi from an eddy off the New South Wales coast; probable spawning populations of Enoploteuthis galaxias have been caught in demersal trawls (Dunning & Brandt 1985).
Females of species that mature at about 50 mm ML are capable of producing between 10 000 and 20 000 eggs, the eggs typically with a maximum diameter of 1.2 mm (Kubota et al. 1982; Riddell 1982). Growth rates of enoploteuthid squids have not been studied although the preponderance of large females in populations of many species (Kubota et al. 1982; Riddell 1982; Brandt 1983) suggests that males have shorter life spans than females.
Enoploteuthids are among the most commonly caught squids in midwater trawls, their abundance in the epipelagic and mesopelagic zones being reflected in their prevalence in the diets of tunas and lancetfish, sharks and marine mammals (Rancurel 1970, 1976; Wolff 1982; Dunning et al. 1993). Small enoploteuthids feed predominantly on pelagic crustaceans, particularly euphausids; larger individuals also take fish and smaller squids (Riddell 1982).
Enoploteuthids are diel vertical migrators and show ontogenetic descent. Larvae are most abundant between 100 and 150 m during the day, and 30 and 50 m at night (Young & Harman 1986). Adults occur at depths between 300 and 600 m during the day, migrating to the upper 150 m at night (Roper & Young 1975).
No endemic species are recorded from Australian waters, although Enoploteuthis galaxias appears to be restricted to southern Australia and New Zealand. Nesis (1979) assigned nine pelagic enoploteuthid species from the Australasian region to three major species groups, according to whether they are tropical, subtropical and peripheral, the boundaries of their distributions being defined largely by the Tropical and Subtropical Convergences.
Diagnosis
Enoploteuthids are characterised by a simple, straight funnel locking apparatus, sharp-toothed suckers or suckers and hooks in biserial rows on the arms and arranged tetraserially on the tentacular clubs. Buccal connectives attach to the dorsal border of the ventral arms, and light organs are present in adults. Males have one or both ventral arms hectocotylised. Many small photophores occur on the ventral surface of the mantle, head and arms, and large photophores on the eyeball (adults not more than 150 mm mantle length). The arrangement, size and number of light organs are genus- and species-specific characteristics. Hooks are strongly developed on the arms and on the tentacular clubs. The subterminal fins are lanceolate with slightly concave posterior borders. In many species, the lateral arms are keeled.
General References
Allan, J. 1945. Planktonic cephalopod larvae from the eastern Australian coast. Records of the Australian Museum 21: 317-350 pls 24-27
Berry, S.S. 1918. Report on the Cephalopoda obtained by the F.I.S. Endeavour in the Great Australian Bight and other southern Australian localities. Biological Results of the Fishing Experiments carried on by the F.I.S. Endeavour 1909-1914 4: 203-298 pls 59-88
Brandt, S.B. 1983. Pelagic squid associations with a warm-core eddy of the East Australian Current. Australian Journal of Marine and Freshwater Research 34: 573-585
Clarke, M.R. 1988. Classification of the genera of recent cephalopods. pp. 4-7 in Clarke, M.R. & Trueman, E.R. (eds). Paleontology and Neontology of Cephalopods. The Mollusca. Vol. 12. San Diego; London : Academic Press.
Dunning, M. & Brandt, S.B. 1985. Distribution and life history of deep-water squid of commercial interest from Australia. Australian Journal of Marine and Freshwater Research 36: 343-359
Dunning, M.C., Clarke, M.R. & Lu, C.C. 1993. Cephalopods in the diet of oceanic sharks caught off eastern Australia. pp. 119-131 in Okutani, T., O'Dor, R.K. & Kubodera, T. (eds). Recent Advances in Cephalopod Fisheries Biology. Tokyo : Tokai University Press.
Kubota, T., Iizuka, K. & Okutani, T. 1982. Some biological aspects of Abralia andamanica from Suruga Bay, Japan (Cephalopoda : Enoploteuthidae). Journal of the Faculty of Marine Science and Technology, Tokai University 15: 333-343
Lu, C.C. & Phillips, J.U. 1985. An annotated checklist of Cephalopoda from Australian waters. Occasional Papers of the Museum of Victoria 2: 21-36
Nesis, K.N. 1979. A brief zoogeographic survey of the pelagic zone around Australia and New Zealand (Cephalopods). Trudy Instituta Okeanologii. Akademiya Nauk SSSR. Moskva 106: 125-139 [in Russian]
Rancurel, P. 1970. Les contenus stomacaux d'Alepisaurus ferox dans le sud-ouest Pacifique (Céphalopodes). Cahiers O.R.S.T.O.M. Serie Océanographique 8(4): 4-87
Rancurel, P. 1976. Note sur les Céphalopodes des contenus stomacaux de Thunnus albacares (Bonnaterre) dans le Sud-ouest Pacifique. Cahiers O.R.S.T.O.M. Serie Océanographique 14(1): 71-80
Roper, C.F.E., Young, R.E. & Voss, G.L. 1969. An illustrated key to the families of the order Teuthoidea (Cephalopoda). Smithsonian Contributions to Zoology No. 13: 1-32
Roper, C.F.E. & Young, R.E. 1975. Vertical distribution of pelagic cephalopods. Smithsonian Contributions to Zoology No. 209: 1-51
Young, R.E. 1977. Ventral bioluminescent countershading in midwater cephalopods. pp. 161-190 in Nixon, M. & Messenger, J.B. (eds). The Biology of Cephalopods. Symp. Zool. Soc. Lond. No. 38. London : Academic Press.
Young, R.E. 1983. Oceanic bioluminscence: an overview of general functions. Bulletin of Marine Science 33(4): 829-845
Young, R.E. & Harman, R.F. 1986. Early life history stages of enoploteuthid squids (Cephalopoda, Teuthoidea, Enoploteuthidae) from Hawaiian waters. Vie et Milieu 35(3/4): 181-201
History of changes
| Published | As part of group | Action Date | Action Type | Compiler(s) |
|---|---|---|---|---|
| 05-Jun-2024 | CEPHALOPODA Cuvier, 1795 | 26-May-2023 | MODIFIED | Dr Mandy Reid |
| 20-Mar-2014 | TEUTHIDA | 20-Mar-2014 | MODIFIED | Dr Julian Finn (NMV) |
| 12-Feb-2010 | (import) |