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Tresus
''Tresus'' is a genus of saltwater clams, marine bivalve mollusks in the family Mactridae. Many of them are known under the common name the horse clam or as species of gaper clam. They are similar to geoducks. Species Species within the genus ''Tresus'' include: * '' Tresus allomyax'' (Coan & Scott, 2000) – strange gaper * '' Tresus capax'' (Gould, 1850) – fat gaper * '' Tresus keenae'' (Kuroda & Habe, 1950) – mirugai clam * '' Tresus nuttallii'' (Conrad, 1837) – Pacific gaper * '' Tresus pajaroanus'' (Conrad, 1857) – lost gaper Habitat These species' habitat is the lower intertidal zones on out to waters as deep as 50–60 feet (13–15 m). They prefer sand, mud, and gravel substrates, normally burying themselves 12–16 inches (30–41 cm), so they are much easier to dig than geoducks. Their preferred substrates are also preferred by butter and littleneck clams, so horse clams are often taken incidentally in commercial harvesting. ''Tresus'' cla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tresus Pajaroanus
''Tresus'' is a genus of saltwater clams, marine bivalve mollusks in the family Mactridae. Many of them are known under the common name the horse clam or as species of gaper clam. They are similar to geoducks. Species Species within the genus ''Tresus'' include: * '' Tresus allomyax'' (Coan & Scott, 2000) – strange gaper * '' Tresus capax'' (Gould, 1850) – fat gaper * '' Tresus keenae'' (Kuroda & Habe, 1950) – mirugai clam * '' Tresus nuttallii'' (Conrad, 1837) – Pacific gaper * '' Tresus pajaroanus'' (Conrad, 1857) – lost gaper Habitat These species' habitat is the lower intertidal zones on out to waters as deep as 50–60 feet (13–15 m). They prefer sand, mud, and gravel substrates, normally burying themselves 12–16 inches (30–41 cm), so they are much easier to dig than geoducks. Their preferred substrates are also preferred by butter and littleneck clams, so horse clams are often taken incidentally in commercial harvesting. ''Tresus'' cla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tresus Allomyax
''Tresus'' is a genus of saltwater clams, marine bivalve mollusks in the family Mactridae. Many of them are known under the common name the horse clam or as species of gaper clam. They are similar to geoducks. Species Species within the genus ''Tresus'' include: * '' Tresus allomyax'' (Coan & Scott, 2000) – strange gaper * '' Tresus capax'' (Gould, 1850) – fat gaper * '' Tresus keenae'' (Kuroda & Habe, 1950) – mirugai clam * '' Tresus nuttallii'' (Conrad, 1837) – Pacific gaper * ''Tresus pajaroanus'' (Conrad, 1857) – lost gaper Habitat These species' habitat is the lower intertidal zones on out to waters as deep as 50–60 feet (13–15 m). They prefer sand, mud, and gravel substrates, normally burying themselves 12–16 inches (30–41 cm), so they are much easier to dig than geoducks. Their preferred substrates are also preferred by butter and littleneck clams, so horse clams are often taken incidentally in commercial harvesting. ''Tresus'' clam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tresus Keenae
''Tresus'' is a genus of saltwater clams, marine bivalve mollusks in the family Mactridae. Many of them are known under the common name the horse clam or as species of gaper clam. They are similar to geoducks. Species Species within the genus ''Tresus'' include: * ''Tresus allomyax'' (Coan & Scott, 2000) – strange gaper * '' Tresus capax'' (Gould, 1850) – fat gaper * '' Tresus keenae'' (Kuroda & Habe, 1950) – mirugai clam * '' Tresus nuttallii'' (Conrad, 1837) – Pacific gaper * ''Tresus pajaroanus'' (Conrad, 1857) – lost gaper Habitat These species' habitat is the lower intertidal zones on out to waters as deep as 50–60 feet (13–15 m). They prefer sand, mud, and gravel substrates, normally burying themselves 12–16 inches (30–41 cm), so they are much easier to dig than geoducks. Their preferred substrates are also preferred by butter and littleneck clams, so horse clams are often taken incidentally in commercial harvesting. ''Tresus'' clams ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tresus Capax
''Tresus capax'' is a species of saltwater clam, marine bivalve mollusk, common name the fat gaper, in the family Mactridae. It also shares the common name horse clam with '' Tresus nuttallii'' a species which is similar in morphology and lifestyle. Both species are somewhat similar to the geoduck (''Panopea generosa'', which is in the family Hiatellidae), though smaller, with shells up to eight inches long (20 cm), weight to 3–4 lb (1.4–1.8 kg). The two species commonly known as horse clams inhabit the Pacific coast intertidal zones: the pacific gaper, ''T. nuttallii'', more abundant south to California; and the fat gaper, ''T. capax'', more abundant north to Alaska. Both have oval and chalky-white or yellow shells with patches of brown periostracum (leather-like skin) on the shell. These clams are also commonly called gapers because their shells are flared around the siphon and do not completely close, rather like geoduck clams. Like geoducks, they ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tresus Nuttallii
''Tresus nuttallii'', common name the Pacific gaper, is a species of saltwater clam, a marine bivalve mollusk in the family Mactridae. It also shares the common name horse clam with ''Tresus capax'', a species which is similar in morphology and lifestyle. Both species are somewhat similar to the Geoduck (''Panopea generosa'' which is in the family Hiatellidae), though smaller, with shells up to eight inches long (20 cm), weight to 3–4 lb (1.4–1.8 kg). Two species commonly known as "horse clams" inhabit the intertidal zone of the West Coast of the United States: the Pacific gaper, ''T. nuttallii'', which is more abundant south to California; and the fat gaper, ''T. capax'', which is more abundant north to Alaska. Both have oval and chalky-white or yellow shells with patches of brown periostracum (leather-like skin) on the shell. These clams are also commonly called "gapers" because their shells are flared around the siphon and do not completely close, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geoduck
The Pacific geoduck ("gooey-duck"; ; ''Panopea generosa'') is a species of very large saltwater clam in the family Hiatellidae. The common name is derived from the Lushootseed ( Nisqually) word . The geoduck is native to the coastal waters of the eastern North Pacific Ocean from Alaska to Baja California. The shell of the clam ranges from to over in length, but the extremely long siphons make the clam itself much longer than this: the "neck" or siphons alone can be in length. The geoduck is the largest burrowing clam in the world. It is also one of the longest-living animals of any type, with a typical lifespan of 140 years; the oldest has been recorded at 179 years old. The precise longevity of geoducks can be determined from annual rings deposited in the shell which can be assigned to calendar years of formation through crossdating. These annual rings also serve as an archive of past marine variability. Etymology The name ''geoduck'' is derived from a Lushootseed ( Nis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mactridae
Mactridae, common name the trough shells or duck clams, is a family of saltwater clams, marine bivalve mollusks in the order Venerida. Description These clams have two short siphons, each with a horny sheath. The shell is shaped like a rounded-cornered equilateral triangle and there is a slight gape at the posterior. Each valve bears two cardinal teeth with four lateral teeth on the right valve and two on the left. The foot is white and wedge-shaped. They mostly inhabit the neritic zone. Ecology Trough shells burrow in sand or fine gravel and never in muddy substrates. Genera According to the World Register of Marine Species (2012), this family contains 37 genera: * '' Anatina'' Schumacher, 1817 * '' Austromactra'' Iredale, 1930 * '' Barymactra'' Cossmann in Cossmann & Peyrot, 1909 * '' Coelomactra'' Dall, 1895 * ''Crassula'' Marwick, 1948 * '' Cyclomactra'' Dall, 1895 * '' Darina'' Gray, 1853 * '' Diaphoromactra'' Iredale, 1930 * '' Eastonia'' Gray, 1853 * '' Harvella'' G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mollusc
Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is estimated between 60,000 and 100,000 additional species. The proportion of undescribed species is very high. Many taxa remain poorly studied. Molluscs are the largest marine phylum, comprising about 23% of all the named marine organisms. Numerous molluscs also live in freshwater and terrestrial habitats. They are highly diverse, not just in size and anatomical structure, but also in behaviour and habitat. The phylum is typically divided into 7 or 8 taxonomic classes, of which two are entirely extinct. Cephalopod molluscs, such as squid, cuttlefish, and octopuses, are among the most neurologically advanced of all invertebrates—and either the giant squid or the colossal squid is the largest known invertebrate species. The gastropods ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bivalve
Bivalvia (), in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class of marine and freshwater molluscs that have laterally compressed bodies enclosed by a shell consisting of two hinged parts. As a group, bivalves have no head and they lack some usual molluscan organs, like the radula and the odontophore. They include the clams, oysters, cockles, mussels, scallops, and numerous other families that live in saltwater, as well as a number of families that live in freshwater. The majority are filter feeders. The gills have evolved into ctenidia, specialised organs for feeding and breathing. Most bivalves bury themselves in sediment, where they are relatively safe from predation. Others lie on the sea floor or attach themselves to rocks or other hard surfaces. Some bivalves, such as the scallops and file shells, can swim. The shipworms bore into wood, clay, or stone and live inside these substances. The shell of a bivalve is composed of calc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Substrate (marine Biology)
Stream substrate (sediment) is the material that rests at the bottom of a stream. There are several classification guides. One is: *Mud – silt and clay. *Sand – Particles between 0.06 and 2 mm in diameter. * Granule – Between 2 and 4 mm in diameter. *Pebble – Between 4 – 64 mm in diameter. *Cobble – between 6.4 and 25.6 cm in diameter *Boulder – more than 25.6 cm in diameter. Stream substrate can affect the life found within the stream habitat. Muddy streams generally have more sediment in the water, reducing clarity. Clarity is one guide to stream health. Marine substrate can be classified geologically as well. See Green et al., 1999 for a reference. Mollusks and clams that live in areas with substrate, and need them to survive, use their silky byssal threads to cling to it. See Cteniodes Ales for reference. See also * Grain size * Substrate (biology) In biology, a substrate is the surface on which an organism (such as a plant, fungus, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commensalism
Commensalism is a long-term biological interaction (symbiosis) in which members of one species gain benefits while those of the other species neither benefit nor are harmed. This is in contrast with mutualism, in which both organisms benefit from each other; amensalism, where one is harmed while the other is unaffected; parasitism, where one is harmed and the other benefits, and parasitoidism, which is similar to parasitism but the parasitoid has a free-living state and instead of just harming its host, it eventually ends up killing it. The commensal (the species that benefits from the association) may obtain nutrients, shelter, support, or locomotion from the host species, which is substantially unaffected. The commensal relation is often between a larger host and a smaller commensal; the host organism is unmodified, whereas the commensal species may show great structural adaptation consistent with its habits, as in the remoras that ride attached to sharks and other fishes. Remo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pea Crab
The pea crab, ''Pinnotheres pisum'', is a small crab in the family Pinnotheridae that lives as a parasite in oysters, clams, mussels, and other species of bivalves. Description Pea crabs are small crustaceans about the size of a pea or dime, with a "smooth dorsal surface of the carapace, or upper exoskeleton". The exoskeleton of males is hard and circular and has eyes and antennae extending from their fronts, and the chelipeds are more robust in males than in females, which have more elongated chelipeds. The bodies of the female pea crabs are often translucent and show the inner organs and gonads as yellow and red, with the males being a "more yellowish-grey with patches of brown". Ecology The relationship between the pea crab and its host is one of parasitism, rather than commensalism, since the host may be harmed by the crab's feeding activities. The pea crab relies solely on its host for food, safety, and oxygen. Pea crabs have a variety of hosts, the most important of whic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
