| Combed octopus | |
|---|---|
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Cephalopoda |
| Order: | Octopoda |
| Family: | Eledonidae |
| Genus: | Eledone |
| Species: | E. massyae |
| Binomial name | |
| Eledone massyae | |
Eledone massyae, the combed octopus, is a small benthic octopus found off the Atlantic coasts of southern South America, particularly Argentina and southern Brazil. [3]
The body is rounded and slightly flattened dorso-ventrally. The head is narrower than the mantle and separated by a slight constriction. The opening in the mantle is very large and the arms are the same length. The suckers are small, separated from one another and deeply anchored in the arm. The third arm possesses a hypocotyl in the male individuals. Also in males, other arms have suckers that decrease in number until the tip of the arm. After the last sucker are two ranges of papillae that diverge on the sides. On female individuals, the arms are not modified. [4]
Females have a variable size ranging from 24 to 91 mm and males vary between 22 to 80 mm. [5]
Eledone massyae feeds mostly on macro crustaceans such as crabs from the Portunidae family as well as polychaetes and mullusks. [5]
Eledone massyae is found seasonally along the continental shelf of Rio de Janeiro. Its distribution ranges from Rio de Janeiro to the Peninsula Valdez in Argentina. [5]
It lives in sandy and muddy areas of the middle and outer continental shelf of the southwestern Atlantic Ocean between 30° and 34°S, mainly in waters off Argentina and southern Brazil. In these areas it appears to be sympatric with a scarcer cogener, Eledone gaucha . [6]
The species is found on the bottom of slopes. During spring and summer, it is found in cold waters of maximum 18 degrees Celsius and around 60 meters deep. In autumn, it is found rather close to continental shelves with a maximum temperature of 21 degrees celsius while in winter, it is found close to continental shelves with subantarctic cold water influences. [5]
The lifespan of E. massyae is approximately around two years. Females die after a single spawning that takes place in autumn around November. [5] [7] The eggs hatch around March. It is supposed that they are attached to a solid substrate such as rocks. [7] Juveniles appear in summer on the continental shelf where they grow and reach sexual maturity in spring or summer of their second year.
Like other species of Eledone, female Eledone massyae are able to store sperm when they are not sexually mature in order to use it when they reach sexual maturity. The sperm could be stored for three months between copulation and spawning. [8]
The process of maturation of E. massyae is different regarding each sex. Females become sexually mature when the ovary enlarges as a result of yolk production. This enlargement occurs late in the life of the individual. In males, the process of sexual maturation is complex and begins early in the individual’s life. It is strongly correlated with body size. [7]
A cephalopod is any member of the molluscan class Cephalopoda such as a squid, octopus, cuttlefish, or nautilus. These exclusively marine animals are characterized by bilateral body symmetry, a prominent head, and a set of arms or tentacles modified from the primitive molluscan foot. Fishers sometimes call cephalopods "inkfish", referring to their common ability to squirt ink. The study of cephalopods is a branch of malacology known as teuthology.
Enteroctopus is an octopus genus whose members are sometimes known as giant octopus.
Octopus cyanea, also known as the big blue octopus or day octopus, is an octopus in the family Octopodidae. It occurs in both the Pacific and Indian Oceans, from Hawaii to the eastern coast of Africa. O. cyanea grows to 16 cm in mantle length with arms to at least 80 cm. This octopus was described initially by the British zoologist John Edward Gray in 1849; the type specimen was collected off Australia and is at the Natural History Museum in London.
Eledone is a genus of octopuses forming the only genus in the family Eledonidae. It is mainly distributed in the northern and southern Atlantic Ocean, with one species, E. palari, described from the southwestern Pacific Ocean and eastern Indian Ocean in waters around Indonesia and Australia and another, E. microsicya, from the western Indian Ocean. One species, E. thysanophora, is now regarded as a synonym of the brush-tipped octopus.
Eledone moschata, the musky octopus, is a species of octopus belonging to the family Octopodidae.
Stauroteuthis gilchristi is a species of small pelagic octopus found at great depths in the south Atlantic Ocean. It is believed to be one of a very small number of octopuses to exhibit bioluminescence, like its sister taxon Stauroteuthis syrtensis.
All extant cephalopods have a two-part beak, or rostrum, situated in the buccal mass and surrounded by the muscular head appendages. The dorsal (upper) mandible fits into the ventral (lower) mandible and together they function in a scissor-like fashion. The beak may also be referred to as the mandibles or jaws.
Eledone gaucha is a species of octopus from the southern Atlantic Ocean. It is a predator of fish, crabs, lobsters and molluscs.
Teuthowenia megalops, sometimes known as the Atlantic cranch squid, is a species of glass squid from the subarctic and temperate waters of the northern Atlantic Ocean. They are moderately sized squid with a maximum mantle length of 40 cm (16 in). Their very large eyes are the source for the specific name megalops. Like other members of the genus Teuthowenia, they are easily recognizable by the presence of three bioluminescent organs (photophores) on their eyeballs.
Octopus minor, otherwise known as the long arm octopus or the Korean common octopus, is a small bodied octopus species distributed along the benthic coastal waters surrounding Eastern China, Japan, and the Korean Peninsula. It lives at depths ranging from 0 to 200 metres. O. minor is commonly found in the mudflats of sub-tidal zones leaving it exposed to significant environmental variations. It is grouped within the class Cephalopoda along with squids and cuttlefish.
Sasakiopus is a genus of octopus containing only one species, Sasakiopus salebrosus, the rough octopus. It is part of the family Enteroctopodidae. Genetic analysis appeared to show that S. salebrosus is the sister taxon of the genera Benthoctopus and Vulcanoctopus, although the former is now considered a synonym of Bathypolypus, the only genus in the family Bathypolypodidae, and the latter as a synonym of Muusoctopus.
Octopus maya, known colloquially as the Mexican four-eyed octopus, is a shallow water octopus that can be found in the tropical Western Atlantic Ocean. It is common to sea grass prairies and coral formations. The species was initially discovered in an octopus fishery in Campeche Mexico, where its close external resemblance to Octopus vulgaris led to its mistaken grouping with the other species. O. maya makes up 80% of octopus catch in the Yucatán Peninsula, while O. vulgaris makes up the remaining 20%.
Sepioloidea lineolata or more commonly known as the striped pyjama squid or the striped dumpling squid is a type of bobtail squid, that inhabits the Indo-Pacific Oceans of Australia. Although it is not quite a cuttlefish, as it does not have a cuttlebone, it is otherwise exactly the same as cuttlefish. Therefore it is a sepioid, not a real cuttlefish. However, it is usually referred to as a cuttlefish for public simplification. It is not a squid either. The striped pyjama squid lives on the seafloor and is both venomous and poisonous. When fully mature, a striped pyjama squid will only be about 7 to 8 centimeters in length. Baby striped pyjama squids can be smaller than 10mm.
Octopus insularis is a species of octopus described in 2008 from individuals found off the coast of Brazil, with a potentially much larger range.
Opisthoteuthis agassizii is a lesser-known, deep-sea octopus first described in 1883 by Addison E. Verrill.
Opisthoteuthis bruuni is a species of finned cirrate octopus found in waters near Antofagasta, Chile. Their tissue is almost jelly-like, and they have short, round bodies.
Opisthoteuthis depressa is an octopus found in waters near Japan.
Bathypolypus sponsalis, commonly called the globose octopus, is a deep sea cephalopod that can be found in both the eastern Atlantic Ocean and the Mediterranean Sea. It possesses many morphological traits adapted to a deep sea environment, including large eggs, reduced gills, no ink sac, and subgelatinous tissues. A distinguishing factor are the relatively large reproductive organs. Their diet consists of predominantly crustaceans and molluscs, but they sometimes consume fish as well. Bathypolypus sponsalis usually dies quickly after reproduction and only spawns once in their lifetime. Sexually mature females have a mantle length of at least 34 mm and sexually mature males have a mantle length of about 24 mm. Juveniles are white and transition to dark brown then to dark purple once maturity is reached.
Opisthoteuths massyae is an octopus living in the eastern Atlantic Ocean.
Octopus sinensis is a mollusk belonging to the class Cephalopoda. Octopus sinensis is a well-known shallow-water benthic octopus species found in the coastal, temperature waters of South Korea, China, and Japan, with the species name, sinensis being Latin for Chinese. Octopus sinensis is closely related to the Atlantic and Mediterranean common octopus, Octopus vulgaris. Because of the morphological similarities, O. sinensis was considered synonymous with Octopus vulgaris until 2017. Octopus sinensis are carnivores that prey upon on many shallow-water animals such as crustaceans and mollusks.
