''Callistoctopus macropus'', also known as the Atlantic white-spotted octopus, white-spotted octopus,Norman, M.D. 2000. ''Cephalopods: A World Guide''. ConchBooks.Bouchet, P. (2014). Callistoctopus macropus (Risso, 1826). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=534558 on 2015-02-01 grass octopus or grass scuttle, is a species of

octopus An octopus (: octopuses or octopodes) is a soft-bodied, eight-limbed mollusc of the order Octopoda (, ). The order consists of some 300 species and is grouped within the class Cephalopoda with squids, cuttlefish, and nautiloids. Like oth ...

found in shallow areas of the

Mediterranean Sea The Mediterranean Sea ( ) is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean basin and almost completely enclosed by land: on the east by the Levant in West Asia, on the north by Anatolia in West Asia and Southern Eur ...

, the warmer parts of the eastern and western Atlantic Ocean, the

Caribbean Sea The Caribbean Sea is a sea of the Atlantic Ocean, North Atlantic Ocean in the tropics of the Western Hemisphere, located south of the Gulf of Mexico and southwest of the Sargasso Sea. It is bounded by the Greater Antilles to the north from Cuba ...

, and the Indo-Pacific region. This octopus feeds on small organisms which lurk among the branches of

coral Corals are colonial marine invertebrates within the subphylum Anthozoa of the phylum Cnidaria. They typically form compact Colony (biology), colonies of many identical individual polyp (zoology), polyps. Coral species include the important Coral ...

Description

''Callistoctopus macropus'' grows to a mantle length of with a total length of . The first pair of arms are a metre or so long, and are much longer than the remaining three pairs. The arms are all connected by a shallow web. This octopus is red, with white blotches on its body, and paired white spots on its arms. When it is disturbed, its colour becomes more intense,

deimatic behaviour Deimatic behaviour or startle display means any pattern of bluffing behaviour in an animal that lacks strong defences, such as suddenly displaying conspicuous eyespots, to scare off or momentarily distract a predator, thus giving the prey anima ...

which may make it appear threatening to a potential predator.

Distribution and habitat

Populations of ''Callistoctopus macropus'' form a

species complex In biology, a species complex is a group of closely related organisms that are so similar in appearance and other features that the boundaries between them are often unclear. The taxa in the complex may be able to hybridize readily with each oth ...

found in the Mediterranean Sea, the temperate and tropical Atlantic Ocean and the Caribbean Sea. It is also present in the Pacific and Indian Oceans. It lives near the shore at depths down to about . Its favoured habitat is sand, rubble or

seagrass meadow A seagrass meadow or seagrass bed is an underwater ecosystem formed by seagrasses. Seagrasses are marine (saltwater) plants found in shallow coastal waters and in the brackish waters of estuaries. Seagrasses are flowering plants with stems and ...

s, and it sometimes buries itself under the sand.

Ecology

''Callistoctopus macropus'' is more fastidious in its diet than is the

common octopus The common octopus (''Octopus vulgaris'') is a Mollusca, mollusk belonging to the class Cephalopoda. ''Octopus vulgaris'' is one of the most studied of all octopus species, and also one of the most intelligent. It ranges from the eastern Atlanti ...

(''Octopus vulgaris''), a species with which it shares some of its range and which feeds by day. ''Callistoctopus macropus'', by contrast, feeds by night. Its method of feeding is to move from one clump of branching coral to another, often ''

Acropora ''Acropora'' is a genus of small polyp stony coral in the phylum Cnidaria. Some of its species are known as table coral, elkhorn coral, and staghorn coral. Over 149 species are described. ''Acropora'' species are some of the major reef corals ...

'' or '' Stylophora'' spp.. The octopus wraps its mantle around a coral head and probes with its arms among the branches, searching for the small fish and invertebrates that seek protection there. It has been found that a number of

grouper Groupers are a diverse group of marine ray-finned fish in the family Epinephelidae, in the order Perciformes. Groupers were long considered a subfamily of the seabasses in Serranidae, but are now treated as distinct. Not all members of this f ...

s (family

Serranidae Serranidae is a large family (biology), family of fishes belonging to the order Perciformes. The family contains about 450 species in 65 genera, including the sea basses and the groupers (subfamily Epinephelinae). Although many species are small, ...

) and other

predatory Predation is a biological interaction in which 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 ...

fish associate with the octopus when it is feeding, pouncing on small organisms that are flushed from the coral head by the octopus. For many years, the breeding habits of this octopus were not known. Then a female was observed attaching short-stalked eggs, measuring , to a hard surface forming a sheet of eggs. The female then brooded the eggs, caring for them by aerating them and keeping them clean. The female octopus stopped feeding at the time the eggs were laid and died soon after they had hatched, as is common among octopus species. The

plankton Plankton are the diverse collection of organisms that drift in Hydrosphere, water (or atmosphere, air) but are unable to actively propel themselves against ocean current, currents (or wind). The individual organisms constituting plankton are ca ...

ic larvae which emerged from the eggs were each about in length with short, seven-suckered arms. They fed on

zooplankton Zooplankton are the heterotrophic component of the planktonic community (the " zoo-" prefix comes from ), having to consume other organisms to thrive. Plankton are aquatic organisms that are unable to swim effectively against currents. Consequent ...

such as crustacean larvae.

References

* Norman M.D. & Hochberg F.G. (2005) ''The current state of Octopus taxonomy.'' Phuket Marine Biological Center Research Bulletin 66:127–154

External links

* {{Taxonbar, from1=Q13449622, from2=Q2235326 Octopodidae Molluscs of the Atlantic Ocean Molluscs of the Indian Ocean Molluscs of the Mediterranean Sea Molluscs of the Pacific Ocean Fauna of the Caribbean Marine molluscs of Africa Marine molluscs of Europe Marine molluscs of North America Cephalopods of Europe Cephalopods described in 1826 Taxa named by Antoine Risso