| Combed octopus | |
|---|---|
Scientific classification  | |
| Domain: | Eukaryota |
| 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 and 80 mm. [5]
Eledone massyae feeds mostly on macro crustaceans such as crabs from the family Portunidae 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]
An octopus 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 other cephalopods, an octopus is bilaterally symmetric with two eyes and a beaked mouth at the centre point of the eight limbs. The soft body can radically alter its shape, enabling octopuses to squeeze through small gaps. They trail their eight appendages behind them as they swim. The siphon is used both for respiration and for locomotion, by expelling a jet of water. Octopuses have a complex nervous system and excellent sight, and are among the most intelligent and behaviourally diverse of all invertebrates.
The southern blue-ringed octopus is one of three highly venomous species of blue-ringed octopuses. It is most commonly found in tidal rock pools along the south coast of Australia. As an adult, it can grow up to 20 centimetres (8 in) long and on average weighs 26 grams (0.9 oz). They are normally a docile species, but they are highly venomous, possessing venom capable of killing humans. Their blue rings appear with greater intensity when they become aggravated or threatened.
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.
Velodona togata is a species of octopus in the monotypic genus Velodona. First described by Carl Chun in 1915, with a second subspecies discovered by Guy Coburn Robson in 1924, it was named for the distinctive membranes on its arms.
All cephalopods possess flexible limbs extending from their heads and surrounding their beaks. These appendages, which function as muscular hydrostats, have been variously termed arms, legs or tentacles.
Eledone moschata, the musky octopus, is a species of octopus belonging to the family Octopodidae.
Graneledone yamana is a species of octopus in the genus Graneledone.
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. These beaks are different from bird beaks because they crush bone while most bird beaks do not.
Eledone gaucha is a species of octopus from the southern Atlantic Ocean. It is a predator of fish, crabs, lobsters and molluscs.
Octopus minor, also known as the long arm octopus or the Korean common octopus, is a small-bodied octopus species distributed along the benthic coastal waters bordering 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 where it is exposed to significant environmental variation. It is grouped within the class Cephalopoda along with squids and cuttlefish.
Sepioloidea lineolata or more commonly known as the striped pyjama squid or the striped dumpling squid is a type of bottletail squid that inhabits the Indo-Pacific Oceans of Australia. 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 centimetres in length. Baby striped pyjama squid can be smaller than 10 millimetres (0.39 in).
Wunderpus photogenicus, the wunderpus octopus, is a small-bodied species of octopus with distinct white and rusty brown coloration. 'Wunderpus' from German “wunder” meaning ‘marvel or wonder’.
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 grimaldii is an octopus found near the Azores.
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.
Opisthoteuthis massyae is an octopus living in the eastern Atlantic Ocean.
Octopus conispadiceus is a species of long-ligula octopus, provisionally placed in the genus Octopus. It was first described by Madoka Sasaki in 1917 based on specimens bought at a fish market in Sapporo, Japan.
Amphioctopus aegina, commonly referred to as the marbled octopus or the sandbird octopus, is a bottom dwelling species residing in the coastal zone of the Indo-West Pacific. Planktonic hatchlings and eggs are laid by females predominantly during the months of January and October, however they have been known to reproduce year-round.
Octopus hubbsorum, is an octopus in the family Octopodidae. It is commonly found along tropical waters along the central Pacific Coast of Mexico. Here, they are one of the most commonly caught cephalopods and are commercially extremely important for the economy.
