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Tremoctopus
''Tremoctopus'' is a genus of pelagic cephalopods, containing four species that occupy surface to mid-waters in subtropical and tropical oceans. They are commonly known as blanket octopuses, in reference to the long, transparent webs that connect the dorsal and dorsolateral arms of the adult females. The other arms are much shorter and lack webbing. Description The common blanket octopus (''Tremoctopus violaceus'') exhibits one of the most extreme sexual size-dimorphism known in any animal near its size or larger. Females may reach in length, whereas the males are 2.4 cm (1 inch). The weight ratio is at least 10,000:1, and can probably reach as much as 40,000:1. The males have a large arm in a spherical pouch modified for mating, known as a hectocotylus. During mating, this arm is detached, and kept by the female in her mantle cavity until used for fertilisation. The male almost certainly dies shortly after mating. There is competition between the males; multiple male a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tremoctopus Gracilis
''Tremoctopus'' is a genus of pelagic cephalopods, containing four species that occupy surface to mid-waters in subtropical and tropical oceans. They are commonly known as blanket octopuses, in reference to the long, transparent webs that connect the dorsal and dorsolateral arms of the adult females. The other arms are much shorter and lack webbing. Description The common blanket octopus (''Tremoctopus violaceus'') exhibits one of the most extreme sexual size-dimorphism known in any animal near its size or larger. Females may reach in length, whereas the males are 2.4 cm (1 inch). The weight ratio is at least 10,000:1, and can probably reach as much as 40,000:1. The males have a large arm in a spherical pouch modified for mating, known as a hectocotylus. During mating, this arm is detached, and kept by the female in her mantle cavity until used for fertilisation. The male almost certainly dies shortly after mating. There is competition between the males; multiple male arm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tremoctopus Robsoni
''Tremoctopus'' is a genus of pelagic cephalopods, containing four species that occupy surface to mid-waters in subtropical and tropical oceans. They are commonly known as blanket octopuses, in reference to the long, transparent webs that connect the dorsal and dorsolateral arms of the adult females. The other arms are much shorter and lack webbing. Description The common blanket octopus (''Tremoctopus violaceus'') exhibits one of the most extreme sexual size-dimorphism known in any animal near its size or larger. Females may reach in length, whereas the males are 2.4 cm (1 inch). The weight ratio is at least 10,000:1, and can probably reach as much as 40,000:1. The males have a large arm in a spherical pouch modified for mating, known as a hectocotylus. During mating, this arm is detached, and kept by the female in her mantle cavity until used for fertilisation. The male almost certainly dies shortly after mating. There is competition between the males; multiple male arm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Common Blanket Octopus
The common blanket octopus or violet blanket octopus (''Tremoctopus violaceus'') is a large octopus of the family Tremoctopodidae found worldwide in the epipelagic zone of warm seas. The degree of sexual dimorphism in this species is very high, with females growing up to two meters in length, whereas males grow to about 2.4 cm. The first live specimen of a male was not seen until 2002 off the Great Barrier Reef. Individual weights of males and females differ by a factor of about 10,000 and potentially more. Males and small females of less than 7 cm have been reported to carry with them the tentacles of the Portuguese man o' war. It is speculated that these tentacles serve both as a defensive mechanism and possibly as a method of capturing prey. This mechanism is no longer useful at larger sizes, which may be why males of this species are so small. The web between the arms of the mature female octopus serves as a defensive measure as well, making the animal appear larger, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Common Blanket Octopus
The common blanket octopus or violet blanket octopus (''Tremoctopus violaceus'') is a large octopus of the family Tremoctopodidae found worldwide in the epipelagic zone of warm seas. The degree of sexual dimorphism in this species is very high, with females growing up to two meters in length, whereas males grow to about 2.4 cm. The first live specimen of a male was not seen until 2002 off the Great Barrier Reef. Individual weights of males and females differ by a factor of about 10,000 and potentially more. Males and small females of less than 7 cm have been reported to carry with them the tentacles of the Portuguese man o' war. It is speculated that these tentacles serve both as a defensive mechanism and possibly as a method of capturing prey. This mechanism is no longer useful at larger sizes, which may be why males of this species are so small. The web between the arms of the mature female octopus serves as a defensive measure as well, making the animal appear larger, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tremoctopus Gelatus
''Tremoctopus gelatus'', the gelatinous blanket octopus, is a species of octopod formally described by Thomas in 1977. The length of ''T. gelatus'' is unknown. The gelatinous blanket octopus lives in pelagic subtropical waters of the Atlantic Ocean The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe .... References {{Taxonbar, from=Q658716 Octopuses Molluscs described in 1977 Molluscs of the Atlantic Ocean ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Portuguese Man O' War
The Portuguese man o' war (''Physalia physalis''), also known as the man-of-war, is a marine hydrozoan found in the Atlantic Ocean and the Indian Ocean. It is considered to be the same species as the Pacific man o' war or blue bottle, which is found mainly in the Pacific Ocean. The Portuguese man o' war is the only species in the genus ''Physalia'', which in turn is the only genus in the family Physaliidae. The Portuguese man o' war is a conspicuous member of the neuston, the community of organisms that live at the ocean surface. It has numerous venomous microscopic nematocysts which deliver a painful sting powerful enough to kill fish, and has been known to occasionally kill humans. Although it superficially resembles a jellyfish, the Portuguese man o' war is in fact a siphonophore. Like all siphonophores, it is a colonial organism, made up of many smaller units called zooids. All zooids in a colony are genetically identical, but fulfill specialized functions such as feeding ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gelatinous Blanket Octopus
''Tremoctopus gelatus'', the gelatinous blanket octopus, is a species of octopod formally described by Thomas in 1977. The length of ''T. gelatus'' is unknown. The gelatinous blanket octopus lives in pelagic subtropical waters of the Atlantic Ocean The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe .... References {{Taxonbar, from=Q658716 Octopuses Molluscs described in 1977 Molluscs of the Atlantic Ocean ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Octopuses
An octopus ( : octopuses or octopodes, see below for variants) 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 center 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. Octopuses inhabit various regions of the ocean, including coral reefs, pelagic waters, and the seabed; some live in the intertidal zone and others at abyssal depths. Most species grow quickly, mature early, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hectocotylus
A hectocotylus (plural: ''hectocotyli'') is one of the arms of male cephalopods that is specialized to store and transfer spermatophores to the female. Structurally, hectocotyli are muscular hydrostats. Depending on the species, the male may use it merely as a conduit to the female, analogously to a penis in other animals, or he may wrench it off and present it to the female. The hectocotyl arm was first described in Aristotle's biological works. Although Aristotle knew of its use in mating, he was doubtful that a tentacle could deliver sperm. The name ''hectocotylus'' was devised by Georges Cuvier, who first found one embedded in the mantle of a female argonaut. Supposing it to be a parasitic worm, in 1829 Cuvier gave it a generic name, combining the Greek word for "hundred" and Latin word for "hollow thing". Anatomy Generalized anatomy of squid and octopod hectocotyli: Variability Hectocotyli are shaped in many distinctive ways, and vary considerably between species. The s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tree Of Life Web Project
The Tree of Life Web Project is an Internet project providing information about the diversity and phylogeny of life on Earth. This collaborative peer reviewed project began in 1995, and is written by biologists from around the world. The site has not been updated since 2011, however the pages are still accessible. The pages are linked hierarchically, in the form of the branching evolutionary tree of life, organized cladistically. Each page contains information about one particular group of organisms and is organized according to a branched tree-like form, thus showing hypothetical relationships between different groups of organisms. In 2009 the project ran into funding problems from the University of Arizona. Pages and Treehouses submitted took a considerably longer time to be approved as they were being reviewed by a small group of volunteers, and apparently, around 2011, all activities ended. History The idea of this project started in the late 1980s. David Maddison was wor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sexual Dimorphism
Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most animals and some plants. Differences may include secondary sex characteristics, size, weight, colour, markings, or behavioural or cognitive traits. These differences may be subtle or exaggerated and may be subjected to sexual selection and natural selection. The opposite of dimorphism is ''monomorphism'', which is when both biological sexes are phenotypically indistinguishable from each other. Overview Ornamentation and coloration Common and easily identified types of dimorphism consist of ornamentation and coloration, though not always apparent. A difference in coloration of sexes within a given species is called sexual dichromatism, which is commonly seen in many species of birds and reptiles. Sexual selection leads to the exaggerated dim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
