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. Members of the genera Chimarrogale, Nectogale, Neomys (Nectogalini) and some members of Sorex (Soricini) are known as water shrews, due to having a semi-aquatic lifestyle.
The American pygmy shrew, also called the eastern pygmy shrew, is a small shrew found throughout much of Alaska, Canada, and the northern contiguous United States, as well as south along the Appalachian Mountains and in a small region in the Colorado and Wyoming Rockies. The species was first discovered in 1831 by naturalist William Cane in Georgian Bay, Parry Sound.
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.
The Shinto shrew is a species of shrew of the genus Sorex that lives only on the islands of Japan. It is a mole-like mammal with a pointed snout, very small ears, and a relatively long tail. Like most shrews, it is tiny, has poor eyesight, and a very good sense of hearing and smell which it uses to locate its prey, mainly insects.
The Inyo shrew is a species of shrew found in the western United States. It is light gray and white in color, with a narrow skull and small body size, very similar in appearance to the related dwarf shrew, but paler and not as large. It can be found in many different habitats, from rocky, mountainous regions to wetlands and riparian areas. Not much is known about its behavioral and reproductive habits. While barely studied, their population is believed to be stable and not under any threat.
