''Doryteuthis gahi'', also known as the Patagonian longfin squid
and Patagonian squid (Spanish: ''calamar patagónico''),
[ is a small-sized squid belonging to the family ]Loliginidae
Loliginidae, commonly known as pencil squids, is an aquatic family of squid classified in the order Myopsida.
Taxonomy
The family Loliginidae was formerly classified in the order Teuthida.
Taxonomic list
The classification below follows ...
. It occurs in coastal waters in the southeastern Pacific Ocean
The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the contin ...
and the southwestern Atlantic Ocean
The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe ...
where it is caught and eaten for food.
Description
The Patagonian squid is a small species and has a mantle length of and a weight of between . The mantle is somewhat elongated and on either side at the posterior end are rhomboidal fins
A fin is a thin component or appendage attached to a larger body or structure. Fins typically function as foils that produce lift or thrust, or provide the ability to steer or stabilize motion while traveling in water, air, or other fluids. Fin ...
, rather less than half the length of the mantle. At the anterior end are four pairs of arms and a pair of tentacles. The third and fourth pairs of arms are longer than the others, and in males, the left fourth arm is heterodactylised near its tip. The tentacles are long and slender, each terminated by a club-shaped "manus" with small, narrow suckers at the edge and slightly larger ones at the centre.[
]
Distribution
This squid occurs in the southeastern Pacific Ocean and the southwestern Atlantic Ocean. In the Pacific its range extends along the coast from southern Peru to southern Chile, and in the Atlantic, from the San Matías Gulf
The San Matias Gulf is an inlet of the Atlantic Ocean off the coast of Patagonia, Argentina. It is bordered by the Río Negro Province to the north and west, and the Valdes Peninsula of the Chubut Province to the south. It is "one of the largest ...
in Argentina southwards to Tierra del Fuego
Tierra del Fuego (, ; Spanish for "Land of the Fire", rarely also Fireland in English) is an archipelago off the southernmost tip of the South American mainland, across the Strait of Magellan. The archipelago consists of the main island, Isla ...
, including the continental shelf around the Falkland Islands
The Falkland Islands (; es, Islas Malvinas, link=no ) is an archipelago in the South Atlantic Ocean on the Patagonian Shelf. The principal islands are about east of South America's southern Patagonian coast and about from Cape Dubouze ...
. It is an open-water species with a depth range from the surface down to about .
Biology
Little is known of the biology of this species, but like all squid, it is a predator
Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...
. Prey items are caught by the tentacles, grasped and moved to the mouth with the help of the arms, and then chewed by the horny beak. In Chile, spawning grounds have been identified at depths of between . Fragile egg masses some long containing about 15 embryos have been found among stems of the kelp ''Lessonia trabeculata
''Lessonia trabeculata'' is a species of kelp, a brown alga in the genus '' Lessonia''. It grows subtidally off the coasts of Peru and northern and central Chile, with the closely related '' Lessonia nigrescens'' tending to form a separate zone i ...
'', particularly in places where the algae has been heavily defoliated, suggesting that a semi-protected environment with adequate water movement is desirable. È spesso preda di Otaria flavescens
The South American sea lion (''Otaria flavescens'', formerly ''Otaria byronia''), also called the southern sea lion and the Patagonian sea lion, is a sea lion found on the western and southeastern coasts of South America. It is the only member ...
, Alectis ciliaris
The African pompano (''Alectis ciliaris''), also known as the pennant-fish or threadfin trevally, is a widely distributed species of tropical marine fish in the jack family, Carangidae. The species is found in tropical waters worldwide, with ad ...
e altri predatori.
Uses
In the Pacific Ocean and off Argentina, this species is mostly caught as bycatch during trawls directed at other species. There is a dedicated fishery in the Falkland Islands where it is an important target species taken from over the Patagonian Shelf
The Argentine (sometimes referred to as Patagonian) Shelf is part of the South American continental shelf belonging to the Argentine Sea on the Atlantic seaboard, south of about 35°S. It adjoins the coasts of Uruguay, Argentina and the Falkla ...
. The total reported world catch in 1999 was , with the largest catch being from the Falkland Islands ().
References
{{Taxonbar, from=Q13596602
Squid
Molluscs of the Atlantic Ocean
Molluscs of the Pacific Ocean
Cephalopods described in 1835
Taxa named by Alcide d'Orbigny