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Homarus Fami
''Homarus'' is a genus of lobsters, which include the common and commercially significant species ''Homarus americanus'' (the American lobster) and ''Homarus gammarus'' (the European lobster). The Cape lobster, which was formerly in this genus as ''H. capensis'', was moved in 1995 to the new genus ''Homarinus''. Description ''Homarus'' is one of three extant genera of clawed lobsters to show dimorphism between claws – a specialisation into a crushing claw and a cutting claw. The other similar genera are '' Nephrops'', which is much more slender, and has grooves along the claws and the abdomen, and ''Homarinus'', the Cape lobster from South Africa, which is even smaller, and has hairy claws. tp://ftp.fao.org/docrep/fao/009/t0411e/t0411e09.pdf Subfamily Nephropinae Dana, 1852 pp. 51–86 in Holthuis (1991). While analyses of morphology suggest a close relationship between ''Homarinus'' and ''Homarus'', molecular analyses using mitochondrial DNA reveal that they are not sister ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Albian
The Albian is both an age (geology), age of the geologic timescale and a stage (stratigraphy), stage in the stratigraphic column. It is the youngest or uppermost subdivision of the Early Cretaceous, Early/Lower Cretaceous epoch (geology), Epoch/series (stratigraphy), Series. Its approximate time range is 113.0 ± 1.0 annum, Ma to 100.5 ± 0.9 Ma (million years ago). The Albian is preceded by the Aptian and followed by the Cenomanian. Stratigraphic definitions The Albian Stage was first proposed in 1842 by Alcide d'Orbigny. It was named after Alba, the Latin name for Aube (river), River Aube in France. A Global Boundary Stratotype Section and Point (GSSP), ratified by the IUGS in 2016, defines the base of the Albian as the first occurrence of the planktonic foraminiferan ''Hedbergellidae, Microhedbergella renilaevis'' at the Col de Pré-Guittard section, Arnayon, Drôme, France. The top of the Albian Stage (the base of the Cenomanian Stage and Upper Cretaceous Series) is defined ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spine (zoology)
In a zoological context, spines are hard, needle-like anatomical structures found in both vertebrate and invertebrate species. The spines of most spiny mammals are modified hairs, with a spongy center covered in a thick, hard layer of keratin and a sharp, sometimes barbed tip. Occurrence Mammals Spines in mammals include the prickles of hedgehogs, and among rodents, the quills of porcupines (of both the New World and the Old), as well as the prickly fur of spiny mice, spiny pocket mice, and of species of spiny rat. They are also found on afrotherian tenrecs of the family Tenrecinae (hedgehog and streaked tenrecs), marsupial spiny bandicoots, and on echidnas (a monotreme). An ancient synapsid, ''Dimetrodon'', had extremely long spines on its backbone that were joined together with a web of skin that formed a sail-like structure. Many mammalian species, like cats and fossas, also have penile spines. The Mesozoic eutriconodont mammal '' Spinolestes'' already displa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rostrum (anatomy)
Rostrum (from Latin ', meaning '':wikt:beak, beak'') is a term used in anatomy for several kinds of hard, beak-like structures projecting out from the head or mouth of an animal. Despite some visual similarity, many of these are Phylogenetics, phylogenetically unrelated structures in widely varying species. Invertebrates * In spiders, the rostrum is a part of the mouth of which it borders the opening in front. Homologous of an upper lip, this outgrowth is especially characterised by the presence of a pocket-shaped secreting organ, the rostral gland, only accessible by the sole means of histology and electron microscopy (external link "archentoflor"). * In crustaceans, the rostrum is the forward extension of the carapace in front of the eyes. It is generally a rigid structure, but can be connected by a hinged joint, as seen in Leptostraca. * Among insects, the rostrum is the name for the piercing insect mouthparts, mouthparts of the order Hemiptera as well as those of the snow s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pleistocene
The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed in 2009 by the International Union of Geological Sciences, the cutoff of the Pleistocene and the preceding Pliocene was regarded as being 1.806 million years Before Present (BP). Publications from earlier years may use either definition of the period. The end of the Pleistocene corresponds with the end of the last glacial period and also with the end of the Paleolithic age used in archaeology. The name is a combination of Ancient Greek () 'most' and (; Latinized as ) 'new'. The aridification and cooling trends of the preceding Neogene were continued in the Pleistocene. The climate was strongly variable depending on the glacial cycle, oscillating between cold Glacial period, glacial periods and warmer Interglacial, int ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Speciation
Speciation is the evolutionary process by which populations evolve to become distinct species. The biologist Orator F. Cook coined the term in 1906 for cladogenesis, the splitting of lineages, as opposed to anagenesis, phyletic evolution within lineages. Charles Darwin was the first to describe the role of natural selection in speciation in his 1859 book ''On the Origin of Species''. He also identified sexual selection as a likely mechanism, but found it problematic. There are four geographic modes of speciation in nature, based on the extent to which speciating populations are isolated from one another: allopatric speciation, allopatric, peripatric speciation, peripatric, parapatric speciation, parapatric, and sympatric speciation, sympatric. Whether genetic drift is a minor or major contributor to speciation is the subject of much ongoing discussion. Rapid sympatric speciation can take place through polyploidy, such as by doubling of chromosome number; the result is progeny wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
European Lobster
''Homarus gammarus'', known as the European lobster or common lobster, is a species of lobster, clawed lobster from the eastern Atlantic Ocean, Mediterranean Sea and parts of the Black Sea. It is closely related to the American lobster, ''H. americanus''. It may grow to a length of and a mass of , and bears a conspicuous pair of claws. In life, the lobsters are blue, only becoming "lobster red" on cooking. Mating occurs in the summer, producing egg (biology), eggs which are carried by the females for up to a year before hatching into planktonic crustacean larvae, larvae. ''Homarus gammarus'' is a highly esteemed food, and is widely lobster fishing, caught using lobster trap, lobster pots, mostly around the British Isles. Description ''Homarus gammarus'' is a large crustacean, with a body length up to and weighing up to , although the lobsters caught in lobster trap, lobster pots are usually long and weigh . Like other crustaceans, lobsters have a hard exoskeleton which t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecular Ecology (journal)
''Molecular Ecology'' is a twice monthly scientific journal covering investigations that use molecular techniques to address questions in ecology, evolution, behavior, and conservation. It is published by Wiley-Blackwell. Its 2022 impact factor is 4.9. It was established in 1992 with Harry Smith as founding editor-in-chief An editor-in-chief (EIC), also known as lead editor or chief editor, is a publication's editorial leader who has final responsibility for its operations and policies. The editor-in-chief heads all departments of the organization and is held accoun ..., while Loren Rieseberg is the current editor. See also * '' Molecular Ecology Resources'' References External links * Ecology journals English-language journals Wiley-Blackwell academic journals Semi-monthly journals Academic journals established in 1992 Molecular ecology {{ecology-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cretaceous
The Cretaceous ( ) is a geological period that lasted from about 143.1 to 66 mya (unit), million years ago (Mya). It is the third and final period of the Mesozoic Era (geology), Era, as well as the longest. At around 77.1 million years, it is the ninth and longest geological period of the entire Phanerozoic. The name is derived from the Latin , 'chalk', which is abundant in the latter half of the period. It is usually abbreviated K, for its German translation . The Cretaceous was a period with a relatively warm climate, resulting in high Sea level#Local and eustatic, eustatic sea levels that created numerous shallow Inland sea (geology), inland seas. These oceans and seas were populated with now-extinct marine reptiles, ammonites, and rudists, while dinosaurs continued to dominate on land. The world was largely ice-free, although there is some evidence of brief periods of glaciation during the cooler first half, and forests extended to the poles. Many of the dominant taxonomic gr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Raffles Bulletin Of Zoology
''The Raffles Bulletin of Zoology'' is a peer-reviewed open-access scientific journal published by the Lee Kong Chian Natural History Museum at the National University of Singapore. Overview It covers the taxonomy, ecology, and conservation of Southeast Asian fauna Fauna (: faunae or faunas) is all of the animal life present in a particular region or time. The corresponding terms for plants and fungi are ''flora'' and '' funga'', respectively. Flora, fauna, funga and other forms of life are collectively .... Supplements are published as and when funding permits and may cover topics that extend beyond the normal scope of the journal depending on the targets of the funding agency. It was established as the ''Bulletin of the Raffles Museum'' in 1928 and renamed ''Bulletin of the National Museum of Singapore'' in 1961, before obtaining its current title in 1971. See also * List of zoology journals References Zoology journals Biannual journals Open access journals En ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossil Record
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Though the fossil record is incomplete, numerous studies have demonstrated that there is enough information available to give a good understanding of the pattern of diversification of life on Earth. In addition, the record can predict and fill gaps such as the discovery of '' Tiktaalik'' in the arctic of Canada. Paleontology includes the study of fossils: their age, method of formation, and evolutionary significance. Specimens are sometimes considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years to 4.1 billion years old. Early edition, published online before print. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thymopides
''Thymopides'' is a genus of deep-water lobsters, comprising the two species ''Thymopides grobovi'' and ''Thymopides laurentae''. Distribution Two species are included in the genus ''Thymopides''. *''Thymopides grobovi'' is found around Heard Island and the Kerguelen Archipelago in the southern Indian Ocean at depths of . *''Thymopides laurentae'' is only known from a single hydrothermal vent on the Mid-Atlantic Ridge at a depth of (). Description ''Thymopides'' differs from related genera such as ''Homarus'', '' Homarinus'' and '' Nephrops'' in having the first pair of pereiopods of similar size and shape, rather than one "crusher" and one "cutter" claw. It differs from others, such as ''Metanephrops'' and '' Eunephrops'' by the lack of a carina behind the antennal spine, by the smaller size of some spines and by the smaller, unpigmented eyes. Taxonomy The genus was first described by R. N. Burukovsky and B. S. Averin in 1976 under the name ''Bellator'', the Latine word for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thymops
''Thymops birsteini'', the Patagonian lobsterette, is a species of lobster found around the coasts of South America, particularly the South Atlantic. It belongs to the monotypic genus ''Thymops''. Distribution ''T. birsteini'' is found on the continental shelf around South America, particularly in the Argentine Sea. In the Atlantic Ocean, it is found south of 37° south, with Uruguay representing the northern extremity of its distribution; on the Chilean (Pacific) side, it is found south of 51° south. Its range includes the areas around the Falkland Islands (''Islas Malvinas'') and areas near South Georgia, extending as far south as 57°, close to the Antarctic Peninsula. It lives at depths of . Description ''T. birsteini'' resembles a typical lobster, with two large claws, four other pairs of pereiopods, and a long pleon (tail). The carapace is granular, especially in the front half, and it bears a rostrum which divides into two points at its tip. The total length may rang ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
