Grimpoteuthis
Encyclopedia
The octopus
Octopus
The octopus is a cephalopod mollusc of the order Octopoda. Octopuses have two eyes and four pairs of arms, and like other cephalopods they are bilaterally symmetric. An octopus has a hard beak, with its mouth at the center point of the arms...

es of the genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 Grimpoteuthis are also known as Dumbo octopuses from the ear-like fins protruding from the top of their head-like bodies, resembling the ears of Walt Disney's flying elephant Dumbo
Dumbo
Dumbo is a 1941 American animated film produced by Walt Disney and released on October 23, 1941, by RKO Radio Pictures.The fourth film in the Walt Disney Animated Classics series, Dumbo is based upon the storyline written by Helen Aberson and illustrated by Harold Pearl for the prototype of a...

. They are bathyal creatures, living at extreme depths of 3000 to 4000 m (9,842.5 to 13,123.4 ft), with some living up to 7000 metres (22,965.9 ft) below sea level, which is the deepest of any known octopus. They are some of the rarest of the Octopoda species. They can flush the transparent layer of their skin at will, and are pelagic animals, as with all other cirrate octopuses. The largest Dumbo octopus ever recorded was 6 feet (1.8 m) in length and weighed 13 pounds (5.9 kg), although the normal size for the various species is thought to be smaller.

They hover above the sea floor, searching for worms, bivalves, pelagic copepod
Copepod
Copepods are a group of small crustaceans found in the sea and nearly every freshwater habitat. Some species are planktonic , some are benthic , and some continental species may live in limno-terrestrial habitats and other wet terrestrial places, such as swamps, under leaf fall in wet forests,...

s, and other crustacean
Crustacean
Crustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span...

s for food. The Dumbo octopus is strange in the way it consumes food in that it swallows its prey whole, which differs from any other kind of octopus. They move by pulsing their arms, shooting water through their funnel, by waving their ear-like fins, or any combination thereof. Males and females differ in their size and sucker patterns. Dissected females have yielded eggs during different stages of development, which has led to the conclusion that females lay eggs constantly, with no distinct breeding season. Male Dumbo octopuses possess an enlarged segment on one of their arms, similar to the hectocotylus
Hectocotylus
A hectocotylus is one of the arms of the male of most kinds of cephalopods that is modified in various ways to effect the fertilization of the female's eggs. It is a specialized, extended muscular hydrostat used to store spermatophores, the male gametophore...

 arm of other cephalopods. It is likely that this modified arm transfers masses of spermatophores into the female during copulation, as occurs in other cephalopods.

Species

  • Grimpoteuthis abyssicola, Red Jellyhead
  • Grimpoteuthis bathynectes
  • Grimpoteuthis boylei
  • Grimpoteuthis challengeri
  • Grimpoteuthis discoveryi
  • Grimpoteuthis hippocrepium
  • Grimpoteuthis innominata, Small Jellyhead
  • Grimpoteuthis meangensis
  • Grimpoteuthis megaptera
  • Grimpoteuthis pacifica
  • Grimpoteuthis plena
  • Grimpoteuthis tuftsi
  • Grimpoteuthis umbellata
  • Grimpoteuthis wuelkeri – possibly same as G. umbellata or G. plena


Several species formerly placed in this genus were moved to other opisthoteuthid genera.

External links

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