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Anelasma Squalicola
''Anelasma'' is a monotypic genus of goose barnacles that live as parasites on various shark hosts. Taxonomy The genus ''Anelasma'' contains a single species, ''Anelasma squalicola''. The nominal species, however, has a very broad distribution and may in fact be a species complex that contain several undescribed species. It has been suggested that ''Anelasma'' diverged from the ancestor it shares with its current closest relatives (the free-living, suspension-feeding species in the genera ''Capitulum'' and '' Pollicipes'') a long time ago. The species may represent the only remaining representative of a previously more numerous clade that made the evolutionary transition from filter-feeding to parasitism. Description left, Velvet belly lanternshark with ''Anelasma'' This barnacle reaches a length of approximately 25 mm. Unlike most barnacles, it has no shell; the outermost integument is its tough, purplish-black mantle, without any calcareous plates. The body protrudes f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Etmopterus Compagnoi
''Etmopterus compagnoi'' is a shark of the family Etmopteridae found in the southeast Atlantic off southwestern Cape Province and northern Natal in South Africa at a depth of 479 to 923 metres. It is sometimes considered conspecific with the brown lanternshark The brown lanternshark or bristled lanternshark (''Etmopterus unicolor'') is a little-known species of deep-sea dogfish shark in the family Etmopteridae. It is found off Japan and New Zealand, and possibly also South Africa and Australia, typi .... References Etmopterus Fish described in 1990 {{Shark-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vestigiality
Vestigiality is the retention, during the process of evolution, of genetically determined structures or attributes that have lost some or all of the ancestral function in a given species. Assessment of the vestigiality must generally rely on comparison with homologous features in related species. The emergence of vestigiality occurs by normal evolutionary processes, typically by loss of function of a feature that is no longer subject to positive selection pressures when it loses its value in a changing environment. The feature may be selected against more urgently when its function becomes definitively harmful, but if the lack of the feature provides no advantage, and its presence provides no disadvantage, the feature may not be phased out by natural selection and persist across species. Examples of vestigial structures (also called degenerate, atrophied, or rudimentary organs) are the loss of functional wings in island-dwelling birds; the human vomeronasal organ; and the hi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monotypic Crustacean Genera
In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispecific" or "monospecific" is sometimes preferred. In botanical nomenclature, a monotypic genus is a genus in the special case where a genus and a single species are simultaneously described. In contrast, an oligotypic taxon contains more than one but only a very few subordinate taxa. Examples Just as the term ''monotypic'' is used to describe a taxon including only one subdivision, the contained taxon can also be referred to as monotypic within the higher-level taxon, e.g. a genus monotypic within a family. Some examples of monotypic groups are: Plants * In the order Amborellales, there is only one family, Amborellaceae and there is only one genus, ''Amborella'', and in this genus there is only one species, namely ''Amborella trichopoda.'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barnacles
A barnacle is a type of arthropod constituting the subclass Cirripedia in the subphylum Crustacea, and is hence related to crabs and lobsters. Barnacles are exclusively marine, and tend to live in shallow and tidal waters, typically in erosive settings. They are sessile (nonmobile) and most are suspension feeders, but those in infraclass Rhizocephala are highly specialized parasites on crustaceans. They have four nektonic (active swimming) larval stages. Around 1,000 barnacle species are currently known. The name is Latin, meaning "curl-footed". The study of barnacles is called cirripedology. Description Barnacles are encrusters, attaching themselves temporarily to a hard substrate or a symbiont such as a whale ( whale barnacles), a sea snake ('' Platylepas ophiophila''), or another crustacean, like a crab or a lobster (Rhizocephala). The most common among them, "acorn barnacles" ( Sessilia), are sessile where they grow their shells directly onto the substrate. Pedunculate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parasitic Castration
Parasitic castration is the strategy, by a parasite, of blocking reproduction by its host, completely or in part, to its own benefit. This is one of six major strategies within parasitism. Evolutionary strategy The parasitic castration strategy, which results in the reproductive death of the host, can be compared with the parasitoid strategy, which results in the host's death. Both parasitoids and parasitic castrators tend to be similar to their host in size, whereas most non-castrating parasites are orders of magnitude smaller than the host. In both strategies, an infected host is much less hospitable to new parasites than an uninfected one. A parasite that ends the reproductive life of its host theoretically liberates a significant fraction of the host's resources, which can now be used to benefit the parasite. The fraction of intact host energy spent on reproduction includes not just gonads and gametes but also secondary sexual characteristics, mate-seeking behavior, competi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Southern Lanternshark
The southern lanternshark (''Etmopterus granulosus'') is a shark of the family Etmopteridae found in the southeast Pacific between latitudes 29°S and 59°S, at depths of between 220 and 1,460 m. This species has been found off Northland, off the Chatham Islands, on the Campbell Plateau, all in New Zealand waters. Its length is up to 60 cm. Reproduction is ovoviviparous, with 10 to 13 pups in a litter, length at birth about 18 cm. They exhibit bioluminescence. Parasites of the southern lanternshark, studied off Chile, include Monogeneans, Digeneans, Cestodes, Nematodes, and Copepodes. In June 2018 the New Zealand Department of Conservation classified ''E. granulosus'' as "Not Threatened" with the qualifier "Secure Overseas" under the New Zealand Threat Classification System The New Zealand Threat Classification System is used by the Department of Conservation to assess conservation priorities of species in New Zealand. The system was developed because the IUCN Re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brown Lanternshark
The brown lanternshark or bristled lanternshark (''Etmopterus unicolor'') is a little-known species of deep-sea dogfish shark in the family Etmopteridae. It is found off Japan and New Zealand, and possibly also South Africa and Australia, typically deeper than . This species can be distinguished from other lanternsharks by its coloration, which is a uniform dark gray or brown without the ventral surface being much darker and clearly delineated from the rest of the body. The brown lanternshark feeds on small bony fishes, cephalopods, and crustaceans. Reproduction is ovoviviparous, with females giving birth to 9–18 young. An unusually high proportion of individuals in Suruga Bay are hermaphrodites, with both male and female characteristics. Taxonomy The brown lanternshark was first described by Robert Engelhardt as ''Spinax unicolor'' in 1912, in the scientific journal ''Zoologischer Anzeiger''. The type specimen was a 55-cm-long female from Sagami Bay, Japan. In 1965, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Great Lanternshark
The great lanternshark (''Etmopterus princeps'') is a shark of the family Etmopteridae found in the northeast and northwest Atlantic 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 an .... Its name was given as at the time of its discovery, it was thought to be bioluminescent, but this has been challenged. Description This species of shark is slender and small, generally found in deep water. They can grow up to . It is a black or a very dark brown, uniformly, in color, and lacks an anal fin. It lives from to . The dorsal fins have an associated spine. References {{DEFAULTSORT:Great lanternshark Etmopterus Fish described in 1904 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fringefin Lanternshark
The fringefin lanternshark (''Etmopterus schultzi'') is a shark of the family Etmopteridae found in the western central Atlantic from Texas to Florida, northern Gulf of Mexico, and Mexico. It is endemic to this area. It is a deep water shark and is found about 220 to 915 meters below the surface, on the upper continental slopes of the Gulf. ''E. schultzi'' is a small shark, about 27–30 cm long and feeds on squid. It is also bioluminescent, which counter-illuminates it and helps with intraspecific interaction. Due to its limited range and the difficulty of collecting deep water species, it has not been evaluated by the IUCN Red List, but due to recent oil spills in the Gulf of Mexico, it is likely that fringefin lanternsharks have decreased in population. Taxonomy The fringefin lanternshark was first identified in 1953 by H.B. Bigelow, W. C. Schroeder, and S. Springer in the ''Bulletin of the Museum of Comparative Zoology'' at Harvard College. Etmopteridae is a family com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Velvet Belly Lanternshark
The velvet belly lanternshark (or simply velvet belly) (''Etmopterus spinax'') is a species of dogfish shark in the family Etmopteridae. One of the most common deepwater sharks in the northeastern Atlantic Ocean, the velvet belly is found from Iceland and Norway to Gabon and South Africa at a depth of . A small shark generally no more than long, the velvet belly is so named because its black underside is abruptly distinct from the brown coloration on the rest of its body. The body of this species is fairly stout, with a moderately long snout and tail, and very small gill slits. Like other lanternsharks, the velvet belly is bioluminescent, with light-emitting photophores forming a species-specific pattern over its flanks and abdomen. The ventral photophores are thought to function in counter-illumination, which camouflages the shark against predators and prey. The bioluminescent flank markings may play a role in intraspecific communication. Young velvet bellies feed mainly on kr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Combtooth Dogfish
The combtooth dogfish (''Centroscyllium nigrum'') is a little-known, deepwater dogfish shark, named after its teeth that are comb-shaped. Description The combtooth dogfish has no anal fin, grooved dorsal spines, two dorsal fins of about same size, a pointed nose, large eyes, small gill slits, a short abdomen, a short caudal peduncle, and is blackish-brown in color with white-tipped fins. Like all dogfish sharks, it has 2 spines in front of its 2 dorsal fins. It grows to a maximum of 50cm. It has a faint tiger-like band held together by the lateral line that has photophores that emit light to attract prey. Immature pups are born at 11-13cm. It has a spiracle behind each eye. Diet It consists of eating small fish, shrimp, and cephalopods. Habits and Habitat It is an uncommon deepwater shark found close to the bottom between 400 and 1,145m. It is found in the eastern Pacific and around Hawaii Hawaii ( ; haw, Hawaii or ) is a state in the Western United States, loc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Black Dogfish
The black dogfish (''Centroscyllium fabricii'') is a species of dogfish shark in the family Etmopteridae. It is common over the outer continental shelf and continental slope at depths of . Females generally inhabit deeper water than males, and depending on the region, smaller sharks may occur at different depths than larger ones. This species is distributed widely in the Atlantic Ocean, from Greenland and Iceland to Virginia and West Africa in the north, and off southwestern Africa and Argentina in the south. The largest member of its family, the black dogfish, typically measures long. It has a stocky, dark brown body that is darker below than above, and bears scattered, minute bioluminescent organs. Its two dorsal fins are preceded by stout spines, and the anal fin is absent. Active and schooling, the black dogfish is an opportunistic predator and scavenger that mainly consumes bony fishes, crustaceans, and cephalopods. It is aplacental viviparous, with females producing litters ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
