Unicuspid

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A unicuspid is a tooth that has only one cusp. [1]

In shrews

The dental formulas of shrews are distinguished by the number of unicuspids. All shrews have (in one half of each jaw) one large incisor followed by a variable number of unicuspids, followed by a complex premolar, followed by three molars. All shrews except for those of the genus Myosorex have one lower unicuspid; Myosorex has two. The genera Blarina , Blarinella , and Sorex have five upper unicuspids. The genera Myosorex, Feroculus , Scutisorex , Suncus , Sylvisorex , Ruwenzorisorex , Cryptotis , Neomys , Soriculus , and Episoriculus have four upper unicuspids. The genera Congosorex , Surdisorex , Solisorex , Paracrocidura , Crocidura , Chimarrogale , Chodsigoa , Megasorex , Nectogale , and Notiosorex have three upper unicuspids. The genera Diplomesodon and Anourosorex have two upper unicuspids. [2]

Dentition

Dentition pertains to the development of teeth and their arrangement in the mouth. In particular, it is the characteristic arrangement, kind, and number of teeth in a given species at a given age. That is, the number, type, and morpho-physiology of the teeth of an animal.

Shrew Family of mammals

The shrew is a small mole-like mammal classified in the order Eulipotyphla. True shrews are not to be confused with treeshrews, otter shrews, elephant shrews, or the West Indies shrews, which belong to different families or orders.

Incisor front teeth present in most (but not all — e.g. armadillos) mammals, located in the premaxilla above and on the mandible below; humans have a total of 8 (2 on each side, top and bottom); opossums have 18

Incisors are the front teeth present in most mammals. They are located in the premaxilla above and on the mandible below. Humans have a total of eight. Opossums have 18, whereas armadillos have none.

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Mole (animal) animal

Moles are small mammals adapted to a subterranean lifestyle. They have cylindrical bodies; velvety fur; very small, inconspicuous ears and eyes; reduced hindlimbs; and short, powerful forelimbs with large paws adapted for digging. The term "mole" is especially and most properly used for "true moles" of the Talpidae family in the order Eulipotyphla found in most parts of North America, Asia, and Europe; although it may also refer to other unrelated mammals of Australia and southern Africa which have similarly evolved the mole body plan. The term is not applied to all talpids; e.g. desmans and shrew-moles differ from the common definition of "mole".

Elephant shrew family of mammals

Elephant shrews, also called jumping shrews or sengis, are small insectivorous mammals native to Africa, belonging to the family Macroscelididae, in the order Macroscelidea. Their traditional common English name "elephant shrew" comes from a perceived resemblance between their long noses and the trunk of an elephant, and their superficial similarity with shrews in the order Eulipotyphla. However, phylogenetic analysis revealed that elephant shrews are not classified with true shrews, but are in fact more closely related to elephants than shrews. In 1997 the biologist Jonathan Kingdon proposed that they instead be called "sengis", a term derived from the Bantu languages of Africa, and in 1998 they were classified into the new clade Afrotheria.

Arctic shrew species of mammal

The Arctic shrew, also known as the blackback shrew or saddlebacked shrew, is a medium-sized shrew found in Canada and the northern United States. Separate species status has been proposed for the maritime shrew which is found in New Brunswick and Nova Scotia and had been considered to be a subspecies of the Arctic shrew. The tundra shrew was formerly considered to be a subspecies of the Arctic shrew.

North American least shrew species of mammal

The North American least shrew is one of the smallest mammals, growing to be only up to 3 inches long. It has a long pointed snout and a tail never more than twice the length of its hind foot. The dense fur coat is either grayish-brown or reddish-brown with a white belly. Its fur becomes lighter in the summer and darker in the winter. Although similar in appearance to several species of rodents, all shrews are members of the order Soricomorpha and should not be mistaken for a member of the Rodentia order. The North American least shrew's eyes are small and its ears are completely concealed within its short fur, giving it very poor eyesight and hearing.

Marsh shrew species of mammal

The marsh shrew, also known as the Pacific water shrew, Bendire's water shrew, Bendire's shrew and Jesus shrew is the largest North American member of the genus Sorex. Primarily covered in dark-brown fur, it is found near aquatic habitats along the Pacific coast from southern British Columbia to northern California. With air trapped in its fur for buoyancy, marsh shrews can run for three to five seconds on top of the water. It measures about 16 cm (6.3 in) in length, including a 7-centimetre (2.8 in)-long tail, and weighs an average of 14.5–16 g (0.51–0.56 oz). The marsh shrew's diet consists mainly of invertebrates, which it hunts on land and in the water. They are rare; their populations are thought to be in decline, and they are considered endangered in parts of their range.

Wildlife of Cameroon

The wildlife of Cameroon is composed of its flora and fauna. Bordering Nigeria, it is considered one of the wettest parts of Africa and records Africa's second highest concentration of biodiversity. To preserve its wildlife, Cameroon has more than 20 protected reserves comprising national parks, zoos, forest reserves and sanctuaries. The protected areas were first created in the northern region under the colonial administration in 1932; the first two reserves established were Mozogo Gokoro Reserve and the Bénoué Reserve, which was followed by the Waza Reserve on 24 March 1934. The coverage of reserves was initially about 4 percent of the country's area, rising to 12 percent; the administration proposes to cover 30 percent of the land area.

<i>Myosorex varius</i> species of mammal

The forest shrew is a species of shrew in the mouse shrew family, Soricidae. It is found in Lesotho, South Africa, and Swaziland. Its natural habitats include temperate forests, dry savanna, Mediterranean-type shrubby vegetation, and temperate grassland. The term "forest shrews" in the plural is sometimes confusingly used to collectively refer to a different genus, Sylvisorex.

Fog shrew species of mammal

The fog shrew is a species of mammal in the family Soricidae. It is endemic to northern California and Oregon in the United States.

Trowbridges shrew species of mammal

Trowbridge's shrew is a species of mammal in the family Soricidae. It is found in southern British Columbia in Canada and in Washington, Oregon, and California in the United States.

Surdisorex is a genus of mammals in the family Soricidae. Surdisorex is one of three genera of African shrews, which, in turn, are one of three living subfamilies of shrews. Species in the genus Surdisorex are called African mole shrews because of their similarity to moles, to which they are not closely related.

Myosoricinae subfamily of mammals

According to the current taxonomy, the Myosoricinae are a subfamily of shrews. As such, they form one of three main types of shrews, the other two being the red-toothed shrews and the white-toothed shrews. They are the only one of the three to be found exclusively south of the Sahara Desert, and so they have been described in English as the African shrews, but also many white-toothed shrews are in Africa and therefore this term is more generally used for shrews from Africa in general. The subfamily has three genera and 20 species:

Handbook of the Mammals of the World (HMW) is a book series from the publisher Lynx Edicions. The nine volumes will be published from 2009. Each mammal family is assessed in a full text introduction with photographs and each species has a text account with a distribution map and illustrations on a plate. This is the second major project by Lynx Edicions since the release of the Handbook of the Birds of the World in 1992. The chief editors are Russell Mittermeier and Don E. Wilson in association with Conservation International, the Texas A&M University and the IUCN. Don E. Wilson is also editor of the reference work Mammal Species of the World.

Scalopinae subfamily of small insectivorous mammals

The Scalopinae, or New World moles, are one of three subfamilies of the family Talpidae, which consists of moles and mole-like animals; the other two subfamilies being the Old World Talpids and the Chinese Shrew-like Moles (Uropsilinae). The Scalpidae are the only Talpidae subfamily to consist entirely of undisputed moles and no mole-like close relatives such as shrew-moles or desmans. They are found virtually everywhere soil conditions permit in North America, except northern Canada and those areas of northeastern Mexico where the soil isn't too sandy. There is also one species which lives in China.

Shrew (stock character) stock character; woman given to violent, scolding, particularly nagging treatment

The shrew – an unpleasant, ill-tempered woman characterised by scolding, nagging, and aggression – is a comedic, stock character in literature and folklore, both Western and Eastern. The best-known work with this theme is probably Shakespeare's play The Taming of the Shrew. The figure represents insubordinate female behaviour in a marital system of polarised gender roles, that is male-dominated in a moral hierarchy.

New Mexico shrew species of mammal

The New Mexico shrew is a species of mammal in the family Soricidae. It is found only in New Mexico in the Capitan, Manzano, and Sandia mountains. Its total length is 103 to 121 millimeters. Its tail length is 39 to 54 millimeters. It weighs 6 to 8 grams. It was included in Sorex monticolus until 1996. It is distinguished from Sorex monticolus by its teeth. The row of unicuspid teeth is longer in Sorex neomexicanus than in Sorex monticolus, and Sorex neomexicanus has a wider space between its first upper unicuspid and second upper unicuspid than Sorex monticolus does.

Paucidentomys is a genus of rodents of a type commonly known as shrew-rats which was discovered in 2012 in a remote rainforest on the Indonesian island, Sulawesi. The genus is monotypic, consisting of the species Paucidentomys vermidax. The name, which is Latin and may be translated as "worm-eating few-toothed mouse", refers to the fact that they have only two teeth and may live exclusively on a diet of earthworms. Paucidentomys vermidax is larger than Melasmothrix naso, Sommeromys macrorhinos and Tateomys macrocercus, similar in size to Tateomys rhinogradoides, smaller than Rhynchomys soricoides and substantially smaller than species of Echiothrix. The face is more elongate than that of any other Sulawesi shrew-rat, but similar in this regard to Rhynchomys. It has a very long rostrum, small eyes, large ears, a soft pelage and a long, thick, hairy and dorsoventrally bi-coloured tail.

References

  1. "unicuspid." Dictionary.Com. 16 June 2010. <http://dictionary.reference.com/browse/unicuspid>.
  2. Merritt, Joseph F. Advances in the Biology of Shrews II. New York: International Society of Shrew Biologists. 2005.