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 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]
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]
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]
^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.]
^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
^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.
Santos, M.B., G.J. Pierce, Á.F. González, F. Santos, M.A. Vázquez, M.A. Santos & M.A. Collins 2001. First records of Taningia danae (Cephalopoda: Octopoteuthidae) in Galician waters (north-west Spain) and in Scottish waters (UK). Journal of the Marine Biological Association of the UK81(2): 355–356.
doi:
10.1017/S0025315401003903
Zeidler, W. 1981. A giant deep-sea squid, Taningia sp., from South Australian waters. Transactions of the Royal Society of South Australia105(4): 218.