vitafert.blogg.se - Flapjack octopus

The Marine Fauna of New Zealand: Octopoda (Mollusca: Cephalopoda). Wissenschaftliche Ergebnisse der Deutschen Tiefsee-Expedition, "Valdivia" 1898-1899, 18 (2): 405-522 + Atlas. For the purposes of this table, a distal field is considered to be absent if suckers there do not show a distinct enlargement.Ĭhun, C. ** DESD = Distal field enlarged sucker diameter PESD = Proximal field enlarged sucker diameter. Species Comparisons (from Villanueva et al., 2002, Villanueva et al., 2008 and Lu, 2010)ĭistal field: Largest sucker, mean position Digestive tract not a simple loop (i.e., intestine makes lateral bends and/or loops. Intestine approximately 1.5 - 2.0 times esophagus (and crop) in length.In this photograph, the lines of white areolar spots are easily seen, especially on the arms. In some species these are difficult to detect or absent.įigure. The extreme flatness of some Opisthoteuthis is apparent in this video. Wing frequently terminates as elongate, simple, pointed cone termination complex in some species.Īlthough the shell lies at an angle to the body axis, the variation in the angle of the spread of its lateral walls presumably is a measure of the "flatness" (i.e., compression of the anterior-poterior body axis) of the octopod.Outer surface of saddle usually with groove (narrow or broad, shallow or deep) outer surface rarely flat.U-shaped, lateral walls (=wings) not parallel (i.e., spread between walls increases toward tips).Small, length approximately half mantle width.

Beaks: Descriptions can be found here: Lower beak upper beak.

Optic lobe kidney-shaped in cross-section.

Two or more bundles of optic tract penetrate white body.

Eyes large, diameter often 60-70% of ML, 50% of head width.

Also note the rather long cirri in this live Opisthoteuthis. Photograph shows multiple web nodules, some of which are indicated by the arrows.

Oral view of Opisthoteuthis grimaldii (?). *Collins and Villanueva (2006) use this same diagnosis to define their family Opisthoteuthidae which contains this single genus.Ĭlick on an image to view larger version & data in a new windowįigure. Radula and posterior salivary glands absent. Two fields of enlarged suckers in mature males. Optic nerves pass through white body in two to four bundles. Shell a flaring U-shape, lateral walls tapering to fine points. Moderate-sized cirrates with small, subterminal fins.

without tooth-like structures in sucker aperture.įull diagnosis of the more restrictive use of the genus (from Collins and Villanueva, 2006):.

with white body penetrated by two or more separate optic nerve bundles.

with areolae present at least in young.

with one or two fields of enlarged suckers on arms of mature males.

These species are also collectively known as the flapjack devilfishes.An introduction to an Opisthoteuthis is seen in this video.įrom Stephanie Bush, "The Opisthoteuthis eggs depicted in this video are preserved specimens, not the eggs laid at the Monterey Bay Aquarium (which are still being lovingly incubated at MBARI's Cold Storage Facility!.)" Brief diagnosis:An opisthoteuthid. The Opisthoteuthis californiana is one of 14 species in the genus Opisthoteuthis. Once the eggs hatch, the hatchlings stay around with their mother for a brief period of time before they are old enough to grow to the benthic stage and survive by itself. The male gender of the flapjack octopus would perform different kinds of sexual rituals to attract the females. The female gender of the Opisthoteuthis californiana produces and hatches around 200-500 eggs. Nesis (1982/87) reports it from the Bering Sea to the Sea of Okhotsk to off central Honshū.

It is also known from Japan, off Kashima-Nada, at 530–560 metres (1,740–1,840 ft). This species has been reported off Eureka Bar, California, at 350 metres (1,150 ft). They swim by moving their fins, pulsing their webbed arms, pushing water through their funnel for jet propulsion, or all three at once. The flapjack preys on small fishes and planktonic crustaceans. They have a gelatinous body, which spreads into a parachute shape when maneuvering through dimly lit water. They have eight jointed legs which are affixed together in an umbrella shape. Their maximum size is 20 centimetres (7.9 in) mantle length. They have fins above their eyes, similar to those found on some species of squid. The flapjack octopus usually appear dark red.