Taningia danae

Dana octopus squid
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Order: Oegopsida
Family: Octopoteuthidae
Genus: Taningia
Species:
T. danae
Binomial name
Taningia danae
Joubin, 1931[2]
Synonyms
  • Cucioteuthis unguiculatus
    Joubin, 1898
  • Cucioteuthis unguiculatus
    Clarke, 1956
  • Cucioteuthis unguiculata
    Rees & Maul, 1956
  • Cucioteuthis unguiculata
    Clarke, 1962
  • Enoploteuthis cookii
    Owen, 1881

Taningia danae, the Dana octopus squid, is a species of squid in the family Octopoteuthidae. It is one of the largest known squid species, reaching a mantle length of 1.7 m (5.6 ft)[3] and total length of 2.3 m (7.5 ft).[4] The largest known specimen, a mature female, weighed 161.4 kg (356 lb).[5][nb a]

Taningia danae is named after Danish fisheries biologist Åge Vedel Tåning (1890–1958), who often traveled on the research vessel Dana.[6]

Ecology

Taningia danae possesses bioluminescence, like other octopoteuthids. Its photophores are some of the largest such organs known to science, the organs being compared in size to fists or lemons. They possess a black membrane over the photophore that may conceal the organs, allowing the squid to blink its lights; this membrane has been compared to eyelids as a result.[7]

In 2005, a Japanese research team headed by Tsunemi Kubodera managed to film T. danae in its natural habitat for the first time. The video footage, shot in deep water off Chichi-jima in the northern Pacific Ocean, shows T. danae emitting blinding flashes of light from photophores on its arms as it attacks its prey. It is believed that this highly maneuverable squid uses the bright flashes to disorient potential prey, as well as to illuminate the prey to make for easier capture in a dark environment. These flashes may also serve a role in courtship and territorial display.[4]

As well as a predatorial characteristic, T. danae bioluminescence has also been suggested to be a defense mechanism. Juveniles of this species have been observed moving rapidly in the direction of potential predators, as if hunting, to disorient and startle the threat with a mock attack.[8]

In 2012, T. danae was filmed twice more during a search for the giant squid for the Discovery Channel Special, Monster Squid: The Giant Is Real.[9]

Still image from the first video footage of a live Taningia danae in its natural habitat.
Arms and buccal mass of T. danae

Remains of T. danae have, on occasion, been found washed ashore on beaches. In 2008, a mantle of T. danae was discovered by students in Bermuda's Grape Bay, while tentacle remnants were found farther along the shore.[10] In early 2013, a 54 kg (119 lb) specimen with a length (excluding arms) of 103 cm (3.38 ft) was trawled at a depth of 240 m (790 ft) off the coast of Estaca de Bares, Galicia, Spain. It was loaned to the Spanish Institute of Oceanography.[11] A largely intact 140 kg (310 lb) specimen was found floating around 100km off the South Australian coast and sent to Flinders University in Adelaide where it was dissected in July 2024. [12]

15N ratios showed that this squid is a top predator.[13][clarification needed] In turn, they are eaten by the sperm whale.[14][15][16]

Notes

a.^ This is the weight of a specimen from the North Atlantic measuring 1.6 m (5.2 ft) in mantle length.[5] The previously reported maximum weight of 61.4 kg (135 lb) for T. danae (based on this same specimen) stems from a typographical error in the original paper[17] of Roper & Vecchione (1993).[5]

References

  1. ^ Barratt, I. & Allcock, L. (2014). "Taningia danae". The IUCN Red List of Threatened Species. 2014: e.T163267A991803. doi:10.2305/IUCN.UK.2014-1.RLTS.T163267A991803.en. Downloaded on 10 March 2018.
  2. ^ Julian Finn (2016). "Taningia danae Joubin, 1931". World Register of Marine Species. Flanders Marine Institute. Retrieved 10 March 2018.
  3. ^ Nesis, K.N. 1982. Abridged key to the cephalopod mollusks of the world's ocean. Light and Food Industry Publishing House, Moscow. 385+ii pp. (in Russian) [Translated into English by B. S. Levitov, ed. by L. A. Burgess 1987. Cephalopods of the world. T.F.H. Publications, Neptune City, NJ. 351pp.]
  4. ^ a b Kubodera, T., Y. Koyama & K. Mori 2006. "Observations of wild hunting behaviour and bioluminescence of a large deep-sea, eight-armed squid, Taningia danae" (PDF). (295 KB) Proceedings of the Royal Society B: Biological Sciences 274(1613): 1029–1034. doi:10.1098/rspb.2006.0236
  5. ^ a b c Roper, C.F.E. & P. Jereb 2010. Family Octopoteuthidae. In: P. Jereb & C.F.E. Roper (eds.) Cephalopods of the world. An annotated and illustrated catalogue of species known to date. Volume 2. Myopsid and Oegopsid Squids. FAO Species Catalogue for Fishery Purposes No. 4, Vol. 2. FAO, Rome. pp. 262–268.
  6. ^ "Taningia danae, a deep-sea bioluminescent squid". The Cephalopod Page. Dr. James B. Wood. Retrieved 10 March 2018.
  7. ^ "Captain Cook's Calamari". seahistory.org. National Maritime Historical Society. Retrieved 12 December 2022.
  8. ^ Young, R.E. & M. Vecchione 1999. Taningia danae Joubin, 1931. Version 1 January 1999. Tree of Life web project.
  9. ^ Monster Squid: The Giant Is Real. Discovery Channel.
  10. ^ Dale, A. 2008. "Monster from the Deep". Bermuda Royal Gazette, 8 July 2008.
  11. ^ Aparece en Galicia un calamar gigante de 54 kilos y más de un metro de largo. Europa Press, 11 February 2013. (in Spanish)
  12. ^ "Rare octopus squid found dead in Southern Ocean dissected by researchers at SA university". abc.net.au. Retrieved 18 July 2024.
  13. ^ Guerreiro, Miguel & Phillips, Richard A & Cherel, Yves & Ceia, Filipe R & Alvito, Pedro & Rosa, Rui & Xavier, José C. 2015. Habitat and trophic ecology of Southern Ocean cephalopods from stable isotope analyses. Marine Ecology Progress Series, published online on 18 June 2015. doi:10.3354/meps11266
  14. ^ Chua, Marcus A.H.; Lane, David J.W.; Ooi, Seng Keat; Tay, Serene H.X.; Kubodera, Tsunemi (5 April 2019). "Diet and mitochondrial DNA haplotype of a sperm whale (Physeter macrocephalus) found dead off Jurong Island, Singapore". PeerJ. 7: e6705. doi:10.7717/peerj.6705. PMC 6452849. PMID 30984481.
  15. ^ Harvey, James T.; Friend, Theresa; McHuron, Elizabeth A. (April 2014). "Cephalopod remains from stomachs of sperm whales (Physeter macrocephalus) that mass-stranded along the Oregon coast". Marine Mammal Science. 30 (2): 609–625. doi:10.1111/mms.12063.
  16. ^ EVANS, K; HINDELL, M (December 2004). "The diet of sperm whales (Physeter macrocephalus) in southern Australian waters". ICES Journal of Marine Science. 61 (8): 1313–1329. Bibcode:2004ICJMS..61.1313E. doi:10.1016/j.icesjms.2004.07.026.
  17. ^ Roper, C.F.E. & M. Vecchione 1993. "A geographic and taxonomic review of Taningia danae Joubin, 1931 (Cephalopoda: Octopoteuthidae), with new records and observations on bioluminescence" (PDF). In: T. Okutani, R.K. O'Dor & T. Kubodera (eds.) Recent Advances in Cephalopod Fisheries Biology. Tokai University Press, Tokyo. pp. 441–456.

Further reading

See also