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Eupentacta Quinquesemita
''Eupentacta quinquesemita'' is a species of sea cucumber, a marine invertebrate with an elongated body, a leathery skin and tentacles surrounding the mouth. It is commonly known as the stiff-footed sea cucumber or white sea cucumber, and occurs on rocky coasts in the northeastern Pacific Ocean. Description ''Eupentacta quinquesemita'' can grow to a length of up to . The tube feet are arranged in four longitudinal rows; they are non-retractable and give the animal a spiny appearance. The skin between the tube feet is smooth, but both body wall and tube feet contain calcareous ossicles that make them stiff. The mouth is surrounded by ten branched feeding tentacles, the two lowest ones being smaller than the rest. The general body colour is white, the tentacles (often the only parts of the animal that are visible) being creamy-white, often with yellowish or pinkish bases. Bits of shell or other fragments often adhere to the tube feet. Distribution and habitat ''E. quinquesemita'' i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. However, only about 14% of these had been described by 2011. All species (except viruses) are given a two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specific name or the specific epithet (in botanical nomenclature, also sometimes i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Holothuroidea
Sea cucumbers are echinoderms from the class Holothuroidea (). They are marine animals with a leathery skin and an elongated body containing a single, branched gonad. Sea cucumbers are found on the sea floor worldwide. The number of holothurian () species worldwide is about 1,717, with the greatest number being in the Asia-Pacific region. Many of these are gathered for human consumption and some species are cultivated in aquaculture systems. The harvested product is variously referred to as '' trepang'', ''namako'', ''bêche-de-mer'', or ''balate''. Sea cucumbers serve a useful role in the marine ecosystem as they help recycle nutrients, breaking down detritus and other organic matter, after which bacteria can continue the decomposition process. Like all echinoderms, sea cucumbers have an endoskeleton just below the skin, calcified structures that are usually reduced to isolated microscopic ossicles (or sclerietes) joined by connective tissue. In some species these can sometim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tentacle
In zoology, a tentacle is a flexible, mobile, and elongated organ present in some species of animals, most of them invertebrates. In animal anatomy, tentacles usually occur in one or more pairs. Anatomically, the tentacles of animals work mainly like muscular hydrostats. Most forms of tentacles are used for grasping and feeding. Many are sensory organs, variously receptive to touch, vision, or to the smell or taste of particular foods or threats. Examples of such tentacles are the eyestalks of various kinds of snails. Some kinds of tentacles have both sensory and manipulatory functions. A tentacle is similar to a cirrus, but a cirrus is an organ that usually lacks the tentacle's strength, size, flexibility, or sensitivity. A nautilus has cirri, but a squid has tentacles. Invertebrates Molluscs Many molluscs have tentacles of one form or another. The most familiar are those of the pulmonate land snails, which usually have two sets of tentacles on the head: when extended ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydroid (zoology)
Hydroids are a life stage for most animals of the class Hydrozoa, small predators related to jellyfish. Some hydroids such as the freshwater '' Hydra'' are solitary, with the polyp attached directly to the substrate. When these produce buds, they become detached and grow on as new individuals. The majority of hydroids are colonial. The original polyp is anchored to a solid substrate and forms a bud which remains attached to its parent. This in turn buds and in this way a stem is formed. The arrangement of polyps and the branching of the stem is characteristic of the species. Some species have the polyps budding directly off the stolon which roots the colony. The polyps are connected by epidermis which surrounds a gastrovascular cavity. The epidermis secretes a chitinous skeleton which supports the stem and in some hydroids, the skeleton extends into a cup shape surrounding the polyp. Most of the polyps are gastrozooids or feeding polyps, but some are specialised reprodu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thyonicola Americana
''Thyonicola americana'' is a species of parasitic sea snail, a marine gastropod mollusc in the family Eulimidae. It infests the sea cucumbers '' Eupentacta quinquesemita'' and '' Eupentacta pseudoquinquesemita'' in Puget Sound and other parts of the northeastern Pacific Ocean. Description The adult female ''Thyonicola americana'' bears little resemblance to a mollusc, having no shell and a coiled worm-like form. While living in the visceral tissues of its host, its central cavity is connected to the large intestine lumen of its host by a thin stalk, inside which is a tubule lined with cilia. The larvae are recognisable as mollusc larvae and have a shell and foot but no velum. They are benthic and move by crawling. Life cycle A female ''T. americana'' larva settles on a suitable host and undergoes metamorphosis into a juvenile which makes its way into the host's gut, possibly through the cloaca, and penetrates the gut wall. The adult female is a worm-like organism which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solaster Stimpsoni
''Solaster stimpsoni'', common names Stimpson's sun star, sun star, orange sun star, striped sunstar, and sun sea star, is a species of starfish in the family Solasteridae. Description ''Solaster stimpsoni'' is a large species, growing up to 50 cm in diameter. It can have 8 to 12 arms, but usually has 10. The aboral surface has a distinctive reddish orange colour and is covered with thick paxillae. The arms are long, slender, and tapering, each with a dark, purplish-grey contrasting stripe, running from the centre of the body to the tip. They contain no pedicellariae. The underside of the arms have two rows of tube feet. Distribution This species is found in the seas of Japan, and along the western coast of the United States, from central California, to as far north as Alaska. Habitat ''Solaster stimpsoni'' usually lives on rocky surfaces in the subtidal, and occasionally the low inter-tidal zones, at depths from 0 to 610 meters. Diet This starfish feeds on various smal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pycnopodia Helianthoides
''Pycnopodia helianthoides'', commonly known as the sunflower sea star, is a large sea star found in the northeast Pacific. The only species of its genus, it is among the largest sea stars in the world, with a maximum arm span of . Adult sunflower sea stars usually have 16 to 24 limbs; their color can vary widely. They are predatory, feeding mostly on sea urchins, clams, snails, and other small invertebrates. Although the species had been widely distributed throughout the northeast Pacific, its population has rapidly declined since 2013. The sea star has been on IUCN list of endangered animals since 2021. Description Sunflower sea stars can grow to have an arm span of in diameter. They are the second-biggest sea star in the world, only second to the poorly known deep water '' Midgardia xandaros'', whose arm span is and its body is 2.6 cm (roughly 1 inch) wide, although ''P. helianthoides'' is the largest known echinoderm by mass. Growth of the sea star b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leptasterias Hexactis
''Leptasterias hexactis'' is a species of starfish in the family Asteriidae, commonly known as the six-rayed star. It is found in the intertidal zone of the western seaboard of the United States. It is a predator and is unusual among starfish in that it broods its eggs and young. Taxonomy ''Leptasterias hexactis'' forms part of a species complex. Over the years, various authorities have discussed the phylogenetic relationships of ''L. epichlora'', ''L. aequalis'' and ''L. hexactis'', all species of ''Leptasterias'' found in the north west Pacific Ocean. The authorities were Bush (1918), Fisher (1930), Chia (1966), Kwast (1990) and Stickle (1992). More recent morphological and behavioural studies have resulted, according to the World Register of Marine Species (WoRMS) in the retention of a single species, ''L. hexactis'', with the other two being considered synonyms. WoRMS now recognizes three subspecies, ''L. hexactis hexactis'' (Stimpson, 1862) ''L. hexactis occidentalis'' Djak ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kelp Greenling
The kelp greenling (''Hexagrammos decagrammus'') is a species of marine ray-finned fish belonging to the family Hexagrammidae, the greenlings. It occurs in the eastern Pacific Ocean Species description and etymology The kelp greenling was first formally described in 1810 as ''Labrax decagrammus'' by the German naturalist Peter Simon Pallas with its type locality given as Cape St. Elias in Alaska. The specific name, ''decagrammus'', means "ten lines" refers to the 5 lateral line canals on each flank, giving a total of 10. Description Kelp greenlings 21 or 22 spines in their first dorsal fin and 24 soft rays in their second dorsal fin while the anal fin contains a single spine and 23 or 24 soft rays. The males are gray to brownish olive in color, dotted with irregular blue spots over the anterior half to two-thirds of their body. Each of these spots has a ring of small rusty spots around it. The females are also gray to brownish in color but they are marked all over with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Evisceration (autotomy)
Evisceration is a method of autotomy involving the ejection of internal organs used by animals as a defensive strategy. Sea cucumbers (Holothuroidea) eject parts of the gut in order to scare and defend against potential predators such as crabs and fish. The organs are regenerated in a few days by cells in the interior of the sea cucumber. Description When stressed, the sea cucumber faces away from the attacker and contracts its body wall muscles sharply. This causes the wall of the cloaca to tear and the anus to gape. The evisceration process in '' Eupentacta quinquesemita'' proceeds as follows: #Three main structures weaken over a period of about 1–3 minutes, become soft and transparent, and eventually separate from their attachments. These are the basal part of the tentacles, the attachment points of the introvert retractor muscles to the longitudinal muscles (there are 10 of these), and the junction of intestine and cloaca. The softening is a state-transformation of the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sclerodactylidae
Sclerodactylidae is a family of sea cucumbers Sea cucumbers are echinoderms from the class Holothuroidea (). They are marine animals with a leathery skin and an elongated body containing a single, branched gonad. Sea cucumbers are found on the sea floor worldwide. The number of holothurian ..., marine invertebrates with elongated bodies, leathery skins and tentacles. Members of the family are characterised by the complex ring of ossicles they have near the anterior end. These may or may not take the form of a short tube but are quite unlike the long tubes found in the phyllophorids. The tentacles number ten to twenty. Digital Nature Archive. Retrieved 2012-02-12. Genera The World Register of Marine Species recognizes the following genera: * genus ''[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
