518.

Steppe Field Mouse

Apodemus witherbyi

French: Mulot de Witherby / German: Steppenwaldmaus / Spanish: Raton de campo de estepa

Taxonomy. Mus sylvaticus witherbyi Thomas, 1902,

Shul, Fars Province, Iran.

Apodemus witherbyi has complex taxonomic history. It was originally described as a sub-species of A. sylvaticus, but morphological and genetic analyses distinguished it, under name A. arianus, from previously described taxa (such as A. fulvipectus, A. falzfeini, and A. hermonensis); holotype of A. arianus, however, corresponds to A. flavicollis, so that name witherby: must be used. B. Krystufek and V. Vohralik in 2009 redefined morphoanatomical characters of A. witherbyi compared with A. wralensis for Turkish populations, and Z. Mohammadi and colleagues in 2014 compared them with A. ponticusfor Iranian ones. Molecular phylogeny ofJ. Darvish and colleagues in 2015 showed that A. witherbyi belongs to the Sylvaemus group and is sister taxon of subclade containing A. uralensis, A. flavicollis, A. ponticus, A. pallipes, and A. hyrcanicus . This species also incudes the recently described A. avicennicus based on genetic data. Monotypic.

Distribution. SE Ukraine (E of Dnieper River), S European Russia, Greece (E Aegean Is of Kos and Rhodes), Turkey (Anatolia), Syria, Lebanon, Israel, NW Jordan, Georgia, Armenia, Azerbaijan, N Iran, and W & § Turkmenistan.

Descriptive notes. Head-body 77-110 mm, tail 75-118 mm, ear 14-18 mm, hindfoot 19-24 mm; weight 16-34 g. The Steppe Field Mouse is medium sized and slender. Dorsal pelage yellowish-brown to wood-brown, sharply delimited white underparts. Tail is bicolored, equal or slightly longer (c.103%) than head-body. Chromosomal complement has 2n = 48, FNa = 46.

Habitat. The Steppe Field Mouse can live in wide variety of environments. In Turkey it has been found both in open habitats and in cedar forests, as well as in shrublands and degraded forest. It needs shrub cover as well as some rocky areas in open grasslands ( Artemisia [ Asteraceae] — Pistacia [ Anacardiaceae], Amygdalus [ Rosaceae | steppes) and is found at up to 2800 m.

Food and Feeding. The Steppe Field Mouse is an omnivorous species, but food consists predominantly of seeds and acorns, followed by fruits, flowers, stems, mushrooms, insects, snails, and earthworms, all theses in variable proportions.

Breeding. Reproduction may be more common in spring and summer. Litter size, estimated from numbers of embryos and placental scars, is 1-7 (average 4-5).

Activity patterns. Steppe Field Mice are nocturnal and terrestrial.

Movements, Home range and Social organization. No information.

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

Bibliography. Aulagnier et al. (2009), Darvish, Javidkar & Siahsarvie (2006), Darvish, Mohammadi et al. (2015), Krystufek & Vohralik (2009), Mohammadi et al. (2014), Musser & Carleton (2005), Musser et al. (1996), Naser; et al. (2007), Orlov et al. (1996).