Chimarrogale platycephala
Creators: name: Mittermeier, Russell A.
name: Wilson, Don E.
Publisher: name: Zenodo
Year: 2018
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Mammalia
Soricomorpha
Soricidae
Chimarrogale
Chimarrogale platycephala

description: 177. Japanese Water Shrew <i>Chimarrogale platycephala</i> <b>French:</b> Chimarrogale du Japon / <b>German:</b> Japanische Wasserspitzmaus / <b>Spanish:</b> Musgano de Japon <b>Other common names:</b> Flat-headed Water Shrew <b>Taxonomy.</b> Sorex platycephalus Temminck, 1842, near Nagasaki and Bungo, Kyushu, Japan. Widely used specific name platycephalus has been changed for gender agreement. Monotypic. <b>Distribution.</b> Endemic to Japan, widely distributed on Honshu and Kyushu. No recent records of extant distribution but fossil records found on Shikoku. <b>Descriptive notes.</b> Head-body 112-135 mm, tail 82-110 mm, hindfoot 23-28 mm; weight 37-55 g. Condylo-incisive lengths are 25-28-4 mm, and tooth rows are 12-12-8 mm. The Japanese Water Shrew is the largest species of Chimarrogale, with long tail but shorter than head-body length. In summer, dorsal pelage is grayish black, venter is mouse gray to olive buff; in winter, dorsal pelage is blackish brown, and venter is whitish. Dorsal and lateral pelage is scattered with guard hairs, especially on rump. Tail is bicolored, being blackish brown above and white below. Braincase is flattened and broad, being flattened and enlarged in lateral view. Tips of teeth are usually unpigmented but sometimes covered with pale brown pigment. There are three upper unicuspids. Chromosomal complement has 2n = 52 and FNa = 100. <b>Habitat.</b> Swift streams or riversides in mountain forests. The Japanese Water Shrew prefers habitats with abundant shelter on riverbanks such as boulders, large rocks or logs with underside cavities orslits, and water-eroded cavities. It occurs at elevations of under 100 m to at least 1000 m, but are most common at 500-1000 m. <b>Food and Feeding.</b> Diet of the Japanese Water Shrew includes aquatic insects, small fish, frogs, salamanders, snails, crayfish, crabs, earthworms, leeches, and spiders. <b>Breeding.</b> The Japanese Water Shrew has two breeding seasons: February—June and October-December. Average number of embryos is 4-2/female (range 1-6). A breeding nest constructed underground with broadleaves has been reported. Longevity is more than three years based on a field survey and examination of museum specimens. <b>Activity patterns.</b> The Japanese Water Shrew is active day and night. It has been reported that it has multiple activity cycles in a day. It is adapted to swim and dive; it uses riverbanks to move up streams and rivers. <b>Movements, Home range and Social organization.</b> Based on trapping data, home ranges were 300-600 m in length along a stream orriver. <b>Status and Conservation.</b> Classified as Least Concern on The IUCN Red List. Most habitats important to the Japanese Water Shrew have been preserved and protected. It is sometimes considered as a pest at fish farms in mountain areas. Typhoons and resulting flooding and habitat loss can be serious threats to this species. <b>Bibliography.</b> Abe (2003), Ohdachi et al. (2009).
description: Published as part of <i>Russell A. Mittermeier &amp; Don E. Wilson, 2018, Soricidae, pp. 332-551 in Handbook of the Mammals of the World – Volume 8 Insectivores, Sloths and Colugos, Barcelona :Lynx Edicions</i> on pages 455-456, DOI: 10.5281/zenodo.6870843