Bigfin squid

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Bigfin squids
Holotype of Magnapinna pacifica, a juvenile
The long-arm squid filmed by DSV Alvin,possibly an adult Magnapinna sp.
The long-arm squid filmed by DSV Alvin,
possibly an adult Magnapinna sp.
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Order: Teuthida
Suborder: Oegopsina
Family: Magnapinnidae
Vecchione & Young, 1998
Genus: Magnapinna
Vecchione & Young, 1998
Species

Magnapinna atlantica
Magnapinna pacifica (type)
Magnapinna talismani
Magnapinna sp. B
Magnapinna sp. C

The bigfin squids are a group of rarely seen cephalopods with a very distinctive morphology. They are placed in the genus Magnapinna and family Magnapinnidae. The family is known only from larval, paralarval, and juvenile specimens, but some authorities believe the adult creature has been seen: Several videos have been taken of animals nicknamed the "long-arm squid", which appear to have a similar morphology. Since none of the adult specimens have ever been captured or sampled, it remains uncertain if they are the same genus, or only distant relatives.

Contents

[edit] Specimens

The first record of this family comes from a specimen (Magnapinna talismani) caught off the Azores in 1907. However, due to the damaged nature of the find, very little information could be discerned and it was lumped in with the mastigoteuthids as Magistoteuthis talismani. In 1956 a similar squid (Magnapinna sp. C) was caught in the South Atlantic, but little was thought of it at the time.

During the 1990s two more immature specimens were found in the Atlantic (Magnapinna sp. A), and three more were found in the Pacific (Magnapinna pacifica). Researchers Michael Vecchione and Richard Young were the chief investigators of the finds, and eventually linked them up to the two previous specimens. Of particular interest was the very large fin size, up to 90% of the mantle length that was responsible for the nickname. Since the number of specimens has been very low, the relationships between the different species are still ambiguous. It has been stated that they may all be the same species, but it is unlikely. The Magnapinna pacifica finds have been called a "cryptid" by cryptozoologist Karl Shuker,[1] who was aware of the other specimens and video evidence but deems it a cryptid because its adult form currently remains undetermined by science.

A single specimen of a fifth species, Magnapinna sp. B, was collected in 2004. Magnapinna sp. A was described as Magnapinna atlantica in 2006.

[edit] Long-armed squids

The first visual record of the long-arm squid dates back to September 1988. The crew of the submersible Nautile encountered a long-armed squid off the coast of northern Brazil, 10°42.91′N, 40°53.43′W, at a depth of 4735 m. In July 1992, the Nautile again came across these creatures, first observing one individual two times during a dive off the coast of Ghana at 3°40′N, 2°30′W and 3010 m depth, and then another one off Senegal at 2950 m[verification needed]. Both were filmed and photographed.[2]

In November 1998, the Japanese manned submersible Shinkai 6500 filmed another long-armed squid in the Indian Ocean south of Mauritius, at 32°45′S, 57°13′E and 2340 m. A third video taken from the ROV of the oil-drilling ship Millennium Explorer in January 2000, at Mississippi Canyon in the Gulf of Mexico (28°37′N, 88°00′W) at 2195 m allowed a size estimate. By comparison with the visible parts of the ROV, the squid was estimated to measure 7 meters with arms fully extended.[2]

The R/V Atalante filmed another Indian Ocean specimen at 19°32′S, 65°52′E and 2576 m, in the area of Rodrigues Island, in May 2000.[2] 2000 was a boon year for observations of these enigmatic animals, for in October, the manned submersible Alvin found yet another long-armed squid in Atwater Valley, Gulf of Mexico (27°34.714′N, 88°30.59′W, 1940 m).

The long-armed squid observed by ROV Tiburon in May 2001.
The long-armed squid observed by ROV Tiburon in May 2001.

These videos did not receive any media attention; in any case, most were brief and fairly blurry. However, in May 2001, some ten minutes of crisp footage of a long-armed squid were acquired by ROV Tiburon, causing a flurry of attention when they were released. These were taken in the Pacific Ocean north of Oʻahu, Hawaiʻi (21°54′N, 158°12′W), at 3380 m.

The specimens in the videos looked very distinct from all previously known squids. Uniquely among cephalopods, the arms and tentacles were of the same length and looked identical (like extinct belemnites). The appendages were also held perpendicular to the body, creating the appearance of strange "elbows". Most remarkable was the length of the elastic tentacles, which has been estimated at stretching up to 15-20 times the mantle length. On close ups of the body and head, it is also apparent that the fins are extremely large, nearly as big as the bigfin squid larvae. While they do appear similar to the larvae, no specimens or samples of the adults have been taken, leaving their exact identity unknown.

[edit] See also

[edit] References

  1. ^ Shuker, Karl P.N. (1998): A supplement to Dr. Bernard Heuvelmans' checklist of cryptozoological animals. Fortean Studies 5: 208-229,
  2. ^ a b c Guerra, A.; González, A.F.; Rocha, F.; Segonzac, M. & Gracia, J. (2002): Observations from submersibles of rare long-arm bathypelagic squids. Sarsia 87(2): 189–192. doi:10.1080/003648202320205274 (HTML abstract)
  • Vecchione, M.; Young, R.E.; Guerra, A.; Lindsay, D.J.; Clague, D.A.; Bernhard, J.M.; Sager, W.W.; Gonzalez, A.F.; Rocha, F.J. & Segonzac, M. (2001): Worldwide observations of remarkable deep-sea squids. Science 294(5551): 2505-2506. doi:10.1126/science.294.5551.2505 (HTML abstract)

[edit] External links

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