Grimpoteuthis

Range and habitat

Species of Grimpoteuthis are assumed to have a worldwide distribution, living in the cold, abyssal depths ranging from 1000 -. Specimens have been found off the coasts of Oregon, the Philippines, Martha's Vineyard, the Azores, New Zealand, Australia, California, Papua and New Guinea, Argentina, Uruguay, and in the Gulf of Mexico.

A fairly recent observation was on 21 June 2022 at 1250 m by the vessel Normand Ocean, which inspects drilling platforms with underwater drones; the vessel was examining chains and risers on the Aasta Hansteen platform outside Trøndelag, Norway. Another recent observation was on 24 May 2023 at this time in Guyana by the vessel Far Samson, which also uses underwater drones.

Further to this, the most recent known recorded observation was on 5th March 2025 by the Vessel "Boka Falcon" with a Workclass Remotely Operated Vehicle working at a depth of 960m in the Gulf Of Guinea approximately 65km South West of Abidjan, Ivory Coast. Two separate sightings approximate 20 minutes apart were observed.

Dumbo octopuses are the deepest living octopuses known, with some specimens captured or observed at hadal depths. One Grimpoteuthis specimen was captured 60 km southeast of Grand Cayman at 7279 m, but this depth is uncertain (as the specimen may have been captured while the net was descending to this depth).

In 2020, Grimpoteuthis was spotted 6957 m deep in the Java Trench, confirming the hadal distribution of this genus.

Species and taxonomy

As noted below, many species collected on the Challenger expedition were initially classified in the genera Cirroteuthis and Stauroteuthis. The persistent confusion and disparity about the taxonomy of these species has been attributed to the poor quality and limited number of specimens available for study.

:{| class="wikitable sortable" |- style = "vertical-align:bottom;" !width=100pt| Species name !width=100pt| Reference !width=190pt| Geographic range ! Depth range (meters) !width=190pt class="unsortable"| Taxonomic notes |- | Grimpoteuthis abyssicola | | Tasman Sea (off New Zealand and southeastern Australia)

| | (off New Zealand)

| | North Pacific (Tufts and Cascadia abyssal Plains, off Oregon) | |- |Grimpoteuthis boylei | | Northeast Atlantic (Porcupine and Madeira abyssal plains) | |- | Grimpoteuthis challengeri | | Northeast Atlantic (Porcupine abyssal plain) | |- | Grimpoteuthis discoveryi | | Northeast Atlantic | |- |Grimpoteuthis feitiana |Tang, Zheng & Zhang, 2025 |Caroline Seamount, western Pacific Ocean |1240 m

| | Southern Australia

| | East Pacific (off Malpelo Island)

| | Emperor Seamounts, North Pacific

| | South Pacific (east of New Zealand)

| | West Pacific (off Meangis Islands, near Philippines)

| | South Pacific (off Papua New Guinea)

| | North Pacific (Tufts and Cascadia abyssal plains off Oregon) | |- | Grimpoteuthis umbellata | Fischer (1883) | North Atlantic (off Morocco, Canary Islands, and the Azores)

| | Northeast and northwest Atlantic | |}

Movement, characteristics, and food supply

Observations of animals in the Atlantic reveal that Grimpoteuthis often rest on the seafloor with the arms and web spread out and uses its arms to slowly crawl along the seafloor. When disturbed, the webbing and arms are contracted to propel the animal off the seafloor and using the mantle fins for rapid locomotion.

The cushiony cartilage that can be found in the proximal position of the fin of Grimpoteuthis is responsible for acting as a support for the thick muscles that allow for rapid locomotion.

Although it has been suggested that species of Grimpoteuthis are capable of jet-propulsion (while swimming using the fins), this has since been deemed unlikely.

Feeding behavior has not been directly observed in Grimpoteuthis, but presumably is similar to Opisthoteuthis which can trap small prey items in the webbing (either by enclosing the prey in the arm webbing or between the webbing and the seafloor) and then use the cirri (fingerlike projections along the arms) to move food to the mouth. Known prey items (from dissected animals) include benthic polychaetes, benthopelagic copepods, amphipods and isopods.

Breeding

The cirrate octopuses are classified as 'continuous spawners': Females carry multiple eggs in various stages of maturation, and only lay one or two eggs at a time, with no seasonality in spawning (however, most of these aspects of reproductive biology have only been confirmed in Opisthoteuthis, not Grimpoteuthis). Mating in cirrate octopuses has never been observed, and unlike other octopuses, members of Cirrata lack a hectocotylus for the transfer of sperm packets. which solidify on contact with the cold seawater. Grimpoteuthis in particular attach their eggs to deep sea corals (octocorals).

Unlike other octopuses, the female cirrate octopus does not guard or incubate the eggs. Grimpoteuthis hatchlings emerge as "fully competent" juveniles with all of the sensory and motor features to survive on their own.

Sexual dimorphism between males and females is less noticeable and consistent in Grimpoteuthis compared to other cirrate octopuses (such as Opisthoteuthis). In some species (e.g., G. bathynectes and G.. discoveryi), the males have enlarged suckers relative to the females, but no such enlargement is found in other Grimpoteuthis species.

Threats

Species of Grimpoteuthis face few direct threats from humans largely due to living at depths of 1000 meters and below. Natural predators of cirrate octopuses include large teleost fish and sharks, and even marine mammals such as sperm whales and seals, but these are mostly predators of other cirrate genera*. Grimpoteuthis* has only been recorded in the stomach contents of a shark.

The Grimpoteuthis do not have an ink sac (as is the case with all cirrate octopuses). Furthermore, the cirrate octopuses lack innervated chromatophores and therefore are not capable of changing color How cirrate octopuses escape or avoid predators is largely unknown.

References

References

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