Common Octopus
Octopus vulgaris
Summary 5
The common octopus (Octopus vulgaris) is the most studied of all octopus species. Its range in the eastern Atlantic extends from the Mediterranean Sea and the southern coast of England to at least Senegal in Africa. It also occurs off the Azores, Canary Islands, and Cape Verde Islands. The species is also common in the Western Atlantic.
Description 6
A medium to large sized octopus reaching up to 1.3 meters in length, with a distinctly warty body.
The arms are thick and stout bearing two rows of longitudinal suckers.
The colour varies from grey-yellow-brown-green and can change according to the situation.
Distribution 7
Western Atlantic: Occurs primarily south of Cape Hatteras, but it is distributed as far north as Connecticut.
Reproduction 8
Octopus vulgaris has individuals of both sexes. During mating, the male approaches the female, who fends him off for a while, but then accepts him. He sits next to her or mounts her, inserting the hectocotylus in her mantle cavity to pass the spermatophores. They may copulate for several hours. The same pair often repeat mating over a period of a week or so, but a male copulates with other females and a female accepts other males. Mating often occurs when the females are immature. Only females ready to lay eggs consistently fend off the males.
Mating System: polygynandrous (promiscuous)
Females become restless and search for a sheltered place where they can lay and brood the eggs without disturbance. The spermatophores are placed in the oviducts and empty cases are discarded. Fertilization takes place in the oviductal glands as the mature eggs pass through them on thir way out of the oviducts. Two secretions from the oviductal glands, together with the mucus, are used to stick the egg stalks together in strings and attach these to a substrate. Eggs are laid in shallow water. They are always attached to a substrate. On rocky shores, females find a hole, a crevice or sheltered place and they often protect their homes with shells, stones and other solid objects that they gather. Coral reefs provide suitable shelter. On sandy or muddy bottom, eggs are laid in empty mollusc shells or in man-made objects such as cans, tins, bottles, tires, boots, and amphorae . In tropical and subtropical waters, eggs are laid throughout the year. The total number of eggs laid by a female varies from 100,000 to 500,000. During egg laying and subsequent brooding, the female rarely leaves the egg mass. She usually does not feed during the entire period of spawning and brooding, which can be as long as 4-5 months at low temperatures. Egg care includes cleaning the eggs with the arm tips and directing jets of water from the funnel through the strings. Intruders, including potential prey, are pushed away, although crabs left overnight may occasionally be eaten. As a rule, females die shortly after the hatching of the last embryos after losing one-third of their pre-spawning weight.
Range number of offspring: 100000 to 500000.
Key Reproductive Features: semelparous ; seasonal breeding ; year-round breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization (Internal ); oviparous
Link to Access Genomic Data 9
http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?id=6645&lvl=0
Sources and Credits
- (c) albert kok, some rights reserved (CC BY-NC-SA), http://www.flickr.com/photos/38118051@N04/3853449562
- (c) sarah faulwetter, some rights reserved (CC BY-NC-SA), http://farm4.static.flickr.com/3189/2674194302_7ce690ffa1_o.jpg
- (c) Biopix, some rights reserved (CC BY-NC), http://www.biopix.com/photos/SDL-Octopus-vulgaris-00002.jpg
- (c) Biopix, some rights reserved (CC BY-NC), http://www.biopix.com/photos/Octopus-vulgaris-00015.JPG
- Adapted by matbio from a work by (c) Wikipedia, some rights reserved (CC BY-SA), http://en.wikipedia.org/wiki/Octopus_vulgaris
- Adapted by matbio from a work by (c) The Marine Biological Association of the United Kingdom, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/16196838
- Adapted by matbio from a work by (c) WoRMS for SMEBD, some rights reserved (CC BY), http://eol.org/data_objects/28470080
- Adapted by matbio from a work by (c) The Regents of the University of Michigan and its licensors, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/18662596
- (c) Emily Rose Sharkey, all rights reserved
