Shrews are small mole-like mammals classified in the order Eulipotyphla. True shrews are not to be confused with treeshrews, otter shrews, elephant shrews, West Indies shrews, or marsupial shrews, which belong to different families or orders.
The red-toothed shrews of the subfamily Soricinae are one of three living subfamilies of shrews, along with Crocidurinae and Myosoricinae. In addition, the family contains the extinct subfamilies Limnoecinae, Crocidosoricinae, Allosoricinae and Heterosoricinae. These species are typically found in North America, northern South America, Europe and northern Asia. The enamel of the tips of their teeth is reddish due to iron pigment. The iron deposits serve to harden the enamel and are concentrated in those parts of the teeth most subject to wear.
The genus Cryptotis is a group of relatively small shrews with short ears, which are usually not visible, and short tails, commonly called small-eared shrews. They have 30 teeth and are members of the red-toothed shrew subfamily. Since 1992, Neal Woodman at the United States National Museum has been in the process of revising the genus. To date, this has resulted in an increase in the number of species from 12 to 30.
Crawford's gray shrew also known as the desert shrew, is a small shrew found in the southwestern United States and northern Mexico. It is a member of the family Soricidae of the order Eulipotyphla. It was the only known member of the genus Notiosorex until two species, N. villai distributed in Tamaulipas, Mexico, and N. evotis distributed along the northwest coast of Mexico, were named. A fourth distinct species, N. cockrumi, was discovered in Arizona and named in 2004.
Neurotrichus is a genus of shrew-like moles. It is classified, together with the fossil genus Quyania, in the tribe Neurotrichini of the subfamily Talpinae. The only living species is the American shrew-mole (N. gibbsii) of the northwestern United States and British Columbia. A fossil species, Neurotrichus columbianus from the Hemphillian of Oregon, was placed in the genus in 1968, but this animal is now thought to be more closely related to the Chinese fossil genus Yanshuella.
The genus Crocidura is one of nine genera of the shrew subfamily Crocidurinae. Members of the genus are commonly called white-toothed shrews or musk shrews, although both also apply to all of the species in the subfamily. With over 180 species, Crocidura contains the most species of any mammal genus. The name Crocidura means "woolly tail", because the tail of Crocidura species are covered in short hairs interspersed with longer ones.
Notiosorex cockrumi, also called Cockrum's gray shrew or Cockrum's desert shrew, is a tiny species of shrews named in 2003. This red-toothed shrew, which is as light as a penny, is the first new mammal species from Arizona since 1977. Its range extends from Arizona to central Sonora, Mexico.
Notiosorex is a genus of shrew from the subfamily Soricinae.
The dwarf shrew is a species of mammal in the family Soricidae endemic to Arizona, Colorado, Montana, Nebraska, New Mexico, South Dakota, Utah, and Wyoming in the United States. The type locality is Estes Park, Colorado, USA.
Nannippus is an extinct genus of three-toed horse endemic to North America during the Miocene through Pleistocene "[http://www.fossilworks.org/cgi-bin/bridge.pl?a=collectionSearch&collection_no=19761", about 13.3—1.8 million years ago (Mya), living around 11.5 million years. This ancient species of three-toed horse grew up to 3.5 feet and weighed between 165 pounds to 199 pounds, which was around the same size as a domestic sheep.
Cynarctus is an extinct genus of the Borophaginae subfamily of canids native to North America. The genus was first founded by W. D. Matthew in 1901, based from a pair of lower jaws, Cynarctus saxitilis, found in the Pawnee Creek Beds of Colorado. It lived during the Middle to Late Miocene 16.0—10.3 mya, existing for approximately 5.7 million years. Fossils have been uncovered in Colorado, California, Maryland, western Nebraska, and Texas. It was likely an omnivore, and lacked the bone-cracking adaptations found in some later borophagines. Newer findings have proved the genus to be described as a large dog-like raccoon, a result from combining characteristics from Canidae with Procyonidae.
A unicuspid is a tooth that has only one cusp.
Equus conversidens, or the Mexican horse, is a dubious Pleistocene species of horse, now extinct, that inhabited North America.
Soriculus is a genus of shrew native to Asia. The Himalayan shrew (Soriculus nigrescens) is the only extant member of the genus, though other species were once included here and there are also several fossil species included here.
Notiosoricini, whose members are known as the North American gray shrews, is a tribe of shrews in the family Soricidae, including the genera Megasorex and Notiosorex. They are found across the southwestern United States and most of Mexico.
Arthur H. Harris is an American mammalogist and paleontologist.
Notiosorex harrisi is an extinct species of shrew from the subfamily Soricinae.
