New record of Kashmir Birch Mouse Sicista concolor leathemi (Thomas, 1893) (Rodentia: Sminthidae) in the Indian Himalaya

Birch mice are grouped under the monotypic genus Sicista Gray, 1827 and placed under the family Sminthidae. They are distributed over the Palearctic ream and the fragmented population of the species Sicista concolor reported from China, North Pakistan and India in Himalayan region. The present communication is a range extension of the Kashmir Birch mouse, Sicista concolor leathemi in Indian Himalaya and first report from Himachal Pradesh.


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Birch mice are grouped under the monotypic genus Sicista Gray, 1827 with 14 recognized species currently distributed over the Palearctic realm (Holden et al. 2017). The genus was earlier variably placed under the families Dipodidae of subfamily Sicistinae (Ellerman 1961;Ellerman & Morrison-Scott 1966;Holden & Musser 2005) and Zapodidae (Corbet & Hill 1992) but at present it is accommodated under the family Sminthidae of superfamily Dipodoidea (Holden et al. 2017 (Holden et al. 2017).
The Kashmir Birch Mouse is found in the alpine and sub-alpine scrub zones in the Himalaya and grassy slopes of moist montane forests at elevations of 2,140-4,000 m. It undergoes prolonged hibernation in winter and digs its own underground burrows. It is nocturnal, fossorial, in habit, and feeds on berries, wild fruits, seeds, fungi, and insects. Little is known about its breeding; it is reported to produce a single litter of 3-6 young annually (Roberts 1997).
It has a longer obscurely bicolored tail that averages over 160% of the head-&-body length, with short hairs throughout the length. The dorsum varies from rufousbrown and greyish-brown to yellowish-brown with conspicuous black guard hairs on back; there is no dark mid-dorsal stripe on the back. The fur of the body is thick and soft; greyish-white (white with gray base) venter without clear demarcation from the dorsum. Ears are short, rounded, thickly clothed with short chocolate brown hairs. Hind feet are long and narrow, about 22-28% of head and body length, lighter than the back, silvery white on upper surface, without plantar pads. Due to overlapping characters, the subspecies flavus was synonymized under S. c. leathami (Holden et al. 2017).
During one faunistic survey in the grasslands of Lahaul Valley of Himachal Pradesh between 16-29 August 2021, we had an opportunity to closely observe and photograph (Image 1, 2) a live small-sized mouse  The animal was quite docile and could be comfortably handled and released thereafter. On the basis of the key morphological characters mentioned in the literature (Ellerman 1961;Roberts 1997;Holden et al. 2017) the animal in the photographs (Image 1, 2) was identified as the Kashmir Birch Mouse Sicista concolor leathemi.
A few scattered literatures are available on the records of rodent fauna from Himachal Pradesh (Lindsay 1926;Chakraborty et al. 2005;Sharma et al. 2008;Sharma & Saikia 2009, 2013, however, none of them mention the occurrence of the Kashmir Birch Mouse in Himachal Pradesh. Therefore, on the basis of photographic evidence, we hereby report this rodent species for the first time from Himachal Pradesh. The present locality is also recorded the southernmost point in its distribution range. The type locality of S. c. leathemi is Krishnye valley, Wardwan (=Warwan), in Kishtwar district of the union territory of Jammu & Kashmir and of S. c. flavus is central Kashmir (c. 3,305 m). The leathami population is  Holden et al. (2017) treated flavus as junior synonym of S. c. leathemi. As per the IUCN Red List of Threatened Species, the global status of the species is 'Least Concern' due to its wide distribution and the lack of known threats (Molur 2016). However, for India S. c. leathemi is categorized as Near Threatened by Molur et al. (2005), which requires revalidation.

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