526.

Korean Field Mouse

Apodemus peninsulae

French: Mulot de Corée / German: Korea-Waldmaus / Spanish: Raton de campo de Corea

Taxonomy. Micromys speciosus peninsulae Thomas, 1907,

“Min-gyoung, 110 mi [= 177 km] S.E. of Seoul[, South Korea]. 1200’ [= 366 m].”

Apodemus peninsulae was classified under subgenus Apodemus by many authors on basis of its morphology. This was later supported by molecular analyses and by morphometric study, as outlined by G. G. Musser and M. D. Carleton in 2005. H. Suzuki and colleagues in 2008 found it to be part of the Apodemus clade and sister taxon of a subclade including A. draco, A. semotus, and A. latronum . Y. Kaneko in 2015 explored the geographical variability of the skull. Monotypic.

528.

Large Japanese Field Mouse

Apodemus speciosus

French: Mulot du Japon / German: Grof 3e Japan-Waldmaus / Spanish: Ratén de campo grande de Japon

Taxonomy. Mus speciosus Temminck, 1844,

Japan .

Distribution. S Siberia and Russian Far East, Mongolia, NE & C China, Korea, and N Japan (Hokkaido).

Apodemus speciosus exhibits significant geographic morphological and genetic variability throughout its range. Different chromosomal races have been described through Robertsonian rearrangement between autosomes, but this 1s not suf-ficient to cause reproductive isolation. In the most recent molecular phylogeny, by Liu Qi and colleagues in 2012, A. speciosus belongs to the Apodemus group in an agrarius subclade, and is sister taxon of a clade including A. chevrieri and A. agrarius . Subspecific taxonomy requires reassessment.

Descriptive notes. Head—body 80-118 mm, tail 75-103 mm, ear 14-17 mm, hindfoot 21-23 mm; weight 19-27 g. A medium-sized species, the Korean Field Mouse has dark yellowish-brown dorsal pelage and is white orgrayish white on belly. It is very similar to the Large Japanese Field Mouse ( A. speciosus), but distinguished by presence of small granules between the four plantar pads of hindfoot. Females bear four pairs of mammae. Chromosomal complement has 2n = 48, FN = 46-48.

Habitat. Scrublands, grasslands, forest edge, secondary forest, plantations, and cultivated fields. In Hokkaido, the Korean Field Mouse was trapped mainly in man-made habitats such as cultivated fields and shelterbelts.

Food and Feeding. The Korean Field Mouse eats large or middle-sized seeds, and small invertebrates.

Breeding. Breeding season is April-August. Females, after gestation of 20 days, give birth to 1-7 young (average 5).

Activity patterns. Korean Field Mice are terrestrial, and crepuscular or nocturnal. They dig simple burrowsin the soil or above it and line them with vegetable material.

Movements, Home range and Social organization. Radius of summer range is less than 30 m.

Status and Conservation. Classified as Least Concern on The IUCN Red Last.

Bibliography. Jones (1956), Kaneko (2010, 2012, 2015), Matsubara et al. (2004), Musser & Carleton (2005), Ohdachi et al. (2015), Serizawa et al. (2002), Smith & Yan Xie (2008), Suzuki et al. (2008).

527.

Small Japanese Field Mouse

Apodemus argenteus

French: Mulot geisha / German: Kleine Japan-Waldmaus / Spanish: Ratén de campo pequeno de Japon

Taxonomy. Mus argenteus Temminck, 1844,

Japan .

Apodemus argenteus is very distinct from others in its genus, and its taxonomic classification is not yet fully understood. G. G. Musser and colleagues in 1996 could not place it in any of the subgenera proposed, and molecular study by K. Serizawa and team in 2000 found it to be distinct and a valid species. Phylogeographic study by H. Suzuki and coworkers in 2004 found

very low genetic variability among differentJapanese populations. In 2003, Suzuki and team had found it to be also very distant from other members of Apodemus, and it has been placed assister taxon of A. gurkha or in its own basal clade by some mammalo-gists, such as Liu Xiaoming and colleagues in 2004 and Suzuki and colleagues in 2008. Re-examination of type series allowed C. Smeenk and coworkers in 1982 to clarify some points of the species’ taxonomy and define a new lectotype. Various subspecies have been named but, as no genetic structure was found, they are not considered here. Monotypic.

Distribution. Japan, including Hokkaido, Honshu, Shikoku, Kyushu, and adjacent islands of Kinkasan, Awashima, Sado, Oki Is (Dogo and Nishino), Awaji, Shodo, Miyajima, Tsushima, Gotd Is (Fukuejima and Nakadorijima), Amakusa-shimoshima, and OsumiIs (Yakushima and Tanegashima).

Descriptive notes. Head-body 65-100 mm, tail 70-110 mm, ear 11-15 mm, hindfoot 17-21 mm; weight 10-20 g. The Small Japanese Field Mouse is a small rodent with a soft and fine fur is pale reddish-brown dorsally and white ventrally. It has a relatively long tail, slightly longer (average 106%) than head-body length. Females bear four pairs of mammae. Chromosomal complement has 2n = 46, FN = 48-52.

Habitat. From lowlands to alpine areas. The Small Japanese Field Mouse prefers mature forests, with a thick leaf layer, from sea level up to more than 2500 m.

Food and Feeding. Like all other Japanese Apodemus, the Small Japanese Field Mouse is primarily granivorous, with variable quantity of insects in its diet.

Breeding. Populations fluctuate during year but maximum density corresponds to summer times, implying that reproduction occurs mostly during spring and summer, and pregnant females were recorded only during May—October. Litter size in the wild was 2-6 (average 3—4), varying regionally and with season. At birth, young are blind and hairless; eyes open at 12-14 days, and they are weaned at days 18-21. Males reach sexual maturity between days 30 and 35.

Activity patterns. The Small Japanese Field Mouse is semi-arboreal. It occupies a more arboreal niche than the Large Japanese Field Mouse ( A. speciosus) and tends to use a horizontally different type of microhabitat, resulting in decreased competition.

Movements, Home range and Social organization. No information.

Status and Conservation. Classified as Least Concern on The IUCN Red Lust.

Bibliography. Abe et al. (2005), Fujimaki (1978), Liu Xiaoming et al. (2004), Matsubara et al. (2004), Musser et al. (1996), Nakata (1986), Ohdachi et al. (2015), Sekijima (2004), Serizawa et al. (2000), Shioya et al. (1990, 1992), Smeenk et al. (1982), Suzuki, Filipucci et al. (2008), Suzuki, Sato et al. (2003), Suzuki, Yasuda et al. (2004).

Distribution. Japan.

Descriptive notes. Head—body 80-140 mm,tail 70-130 mm, ear 13-17 mm, hindfoot 22-28 mm; weight 20-60 g. The LargeJapanese Field Mouse is a medium-sized to large mouse with long tail. It has brown to orange-brown dorsal pelage and snow-white belly. Females bear four pairs of mammae. Karyotype 2n = 46-48, FN = 56.

Habitat. In lowlands of central Japan, the Large Japanese Field Mouse was collected along riverbanks, floodplain grassland and tall herbs, and paddyfields broadleaf forests with nut-producing trees are also preferred, in addition to forests and plantations. Y. Takada and colleagues reported in 1999 that populations of this mouse on Izu Islands commonly inhabit crop fields near human habitation, as well as woodlands.

Food and Feeding. Diet includes roots and stems of herbaceous plants, seeds, berries, and to lesserextent insects. It consumes fruits ofJapanese walnut ( Juglans ailanthifolia, Juglandaceae); either it eats the contents immediately after finding walnuts, or it hoards the nuts on the ground (scatter-hoarding) or in underground nests (larderhoarding) for later use. The Large Japanese Field Mouse is also a disperser of Camellia japonica (Theaceae) seeds.

Breeding. Breeding season varies geographically, mainly April/May-September/October in north and October-March in south. Females had average of 3-2 embryos in spring, against 5-6 in autumn. Gestation period is 19-26 days. Litter size is 2-12 (average 4-6).

Activity patterns. Large Japanese Field Mice are terrestrial and nocturnal.

Movements, Home range and Social organization. Home ranges were 7906 m? (diameter 100 m) and 8500 m?* (diameter 104 m) for males, and 3062 m? (diameter 62 m) and 3175 m* (diameter 64 m) for females. Ranges of males overlap randomly while those of females are mutually exclusive, and there is no evidence of pair bonds. Home ranges of both sexes were significantly larger during breeding season.

Status and Conservation. Classified as Least Concern on The IUCN Red List.

Bibliography. Abe et al. (2006), Kaneko (1979), Liu Qi etal. (2012), Matsubara et al. (2004), Murakami (1974), Ohdachi et al. (2015), Suzuki et al. (1994), Takada (1983), Takada et al. (1999), Tatsukawa & Murakami (1976), Tomozawa etal. (2010).