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Midday Jird

Meriones meridianus

French: Mérione du midi / German: Mittagsrennratte / Spanish: Gerbillo de mediodia

Other common names: Midday Gerbil

Taxonomy. Mus meridianus Pallas, 1773,

type locality unknown. Restricted by V. G. Heptner in 1936 to Dosang, Astrakhans-kaya Oblast, south-eatern Russia.

Meriones meridianus exhibits high morphological and chromosomalvariabil-ity throughout its range. Molecular study has shown that, as currently constituted, it contains two clades, the first including M. cheng: and various Chinese localities and the second one also in China. The two clades were sympatric in one locality (Turpan, in north-west China). A recent morphometrical study showed that M. meridianus from Middle East are distinct from those of Far East, but three distinct lineages corresponding with three mitochondrial clades were recorded in a subsequent analysis. Pending further revisions of this taxon we keep the species as valid, but taxonomy of M. meridianusstill requires attention and cryptic species may be described in future. Monotypic.

Distribution. S European Russia, S Kazakhstan, Uzbekistan, Turkmenistan, Kyrgyzstan, Tajikistan, NE Iran, N Afghanistan, NW & NC China (Xinjiang, Gansu, Qinghai, Inner Mongolia [= Nei Mongol], Ningxia, N Shaanxi, N Shanxi, and NW Hebei), and S Mongolia.

Descriptive notes. Head-body 90-144 mm, tail 85-135 mm, ear 10-19 mm, hindfoot 25-34 mm; weight 24-60 g. The Midday Jird is a medium-sized jird with tail length equal to head-body length and with densely hairy soles of feet. Dorsal pelage is light yellow gray to brown, and venter white with some brown stripes on chest. Tail ends with small pencil of dark hairs. Chromosomal complement has 2n = 50, FN = 78.

Habitat. Found in all sandy deserts of Central Asia, but may occasionally live in steppic zones. The Midday Jird inhabits sand dunes, steppes, grasslands, cultivated fields, and fallow lands in arid zones.

Food and Feeding. Plants, seeds, and insects constitute the diet of Midday Jirds. They store food in their burrows and do not hibernate.

Breeding. Reproduction can occur throughoutyear, but is mostly in April-September in northern parts and February/March—October in southern parts, with a reduction in breeding activity during winter months. Litter size is 1-12, with average ofsix.

Activity patterns. The Midday Jird is primarily nocturnal, but active also in morning or during day in winter. This terrestrial rodent digs deep burrows at base and under roots of thorn scrub.

Movements, Home range and Social organization. Information suggests that Midday Jirds congregate in large colonies, with clear social structure.

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

Bibliography. Aulagnier et al. (2009), Ito et al. (2010), Lay (1967), Nanova (2014), Smith & Yan Xie (2013), Vinogradov et al. (1936), Yazdi et al. (2012).