Pygeretmus shitkovi Kuznetsov 1930
Creators: name: Don E. Wilson
name: Russell A. Mittermeier
name: Thomas E. Lacher, Jr
Publisher: name: Lynx Edicions
Year: 2017
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Mammalia
Rodentia
Dipodidae
Pygeretmus
Pygeretmus shitkovi

description: 22.
Greater Fat-tailed Jerboa
Pygeretmus shitkovi
French: Gerboise de Zhitkov / German: GroRRe Fettschwanzspringmaus / Spanish: Jerbo de cola grasa grande
Other common names: Zhitkov's Jerboa
Taxonomy. Alactagulus shitkovi Kuznetsov, 1930,
Rybachye, Alakulskiy Rayon, Almaty Region, Kazakhstan.
Pygeretmus shitkovi is in the subgenus Pygeretmus. Monotypic.
Distribution. SE Kazakhstan in Lake Valley Balkhash, and and NE Lake Alakol basins, Ili River Betpak-Dala Desert (Karaganda, Jambyl, and Almaty regions).
Descriptive notes. Head-body 86-124 mm, tail 92-141 mm, ear 28-37 mm, hindfoot 40-45 mm; weight 40-86 g. There is no significant secondary sexual dimorphism. Condylo-basal lengths of skulls are 25-5-28-4 mm, zygomatic breadths are 20-7-24-1 mm, and maxillary tooth row lengths are 5-1-5-9 mm. Head and dorsum are light dim yellowish or brownish gray; lips, throat, and inner surfaces of thighs are white; sides and ventral pelage are light ocherous;tail is relatively short and fatty; and tail banner is narrow and notflattened, bicolored, with long brownish black subterminalfield (15-20 mm) and extremely short white terminal tuft (3-5 mm). Toes of hindfeet are covered from below with thin, short (4-5 mm) and soft white hairs not forming brushes; conic calluses at bases of toes are well expressed. Auditory bullae are weakly inflated. Mastoid cavity is extremely small and not subdivided into sections; tympanic cavity is mediumsized. Front surfaces of incisors are white; incisors are significantly deflected forward. P! usually is absent, but if it exists,it is extremely small. Molars are high-crowned, with terraced masticatory surfaces; crown heights of unworn molars are 140-180% of their lengths. Glans penisis lanceolate, flattened, 3-3-3-4 mm long and 1-5-1-8 mm wide, compressed in dorsoventral direction, subdivided by deep and wide longitudinal dorsal depression into two lateral lobes; surfaces of lobes are covered by single-vertex, backward-directed aciculae, markedly increasing in size in backward direction; and aciculae are arranged in 10-12 longitudinal rows, with 12-14 aciculae in each row. Os penis (baculum) is absent. Chromosomal complement has 2n = 48 and FN = 92.
Habitat. Clay saline depressions along low banks of dry river beds and lakes with dense succulent chenopods (Amaranthaceae) such as Anabasis, Atriplex, Camphorosma, Climacoptera, Kochia, and Salsola.
Food and Feeding. The Greater Fat-tailed Jerboa is mainly folivorous. Its diet contains green plant parts in all seasons, but their relative dominance gradually decreases from spring to autumn. Role of seeds in the diet increases in the second one-half of summer and autumn.
Breeding. Breeding of the Greater Fat-tailed Jerboa begins in March—-May and, after interruption in June, ends in July-August. Litters have 3-8 young (usually 4-5). Overwintering females can produce two litters per year. Yearlings born in spring are sexually mature by the next autumn at c.4 months old; those born in autumn are mature by the end of the next spring at c.7 months old. Gestation is estimated at 25-27 days.
Activity patterns. The Greater Fat-tailed Jerboa is nocturnal. Aboveground activity starts 30-50 minutes after sunset in spring and autumn and 15-20 minutes after sunset in summer. Activity ends one hour before sunrise, but some individuals can be active 5-15 minutes after sunrise. Hibernation lasts from end of September and first of November to mid-March.
Movements, Home range and Social organization. Escape behavior of the Greater Fattailed Jerboa is characterized by running fast over a short distance and hiding in one of its numerous shelter burrows. Home range during the breeding season is ¢.750 m? for males and ¢.500 m?* for females. During the non-breeding season, home ranges increase to 0-21-0-35 ha. Summer burrows usually consist of a main tunnel, starting from a main entrance at the ground’s surface and sloping down with several right-angled turns to the nest chamber, and 1-2 short additional tunnels leading from upper part of main tunnel to emergency exits, dug up from inside almost to the ground’s surface. Entrance is usually closed with soil plug 5-7 cm long in spring and autumn and up to 33 cm long in summer. Total lengths of tunnels are 125-595 cm, usually 235-320 cm in females’ burrows and 65-460 cm (average 210 cm) in males’ burrows; nest chamber is 14-16 cm in diameter and 55 cm deep in spring, 45 cm deep in summer, and 70 cm deep in autumn. Winter burrows are similar in architecture to summer burrows but deeper; total lengths of tunnels of winter burrows are 180-455 cm, and they are 52-132 cm deep. Night shelter burrows are simple, with one tunnel 50-60 cm in length, passing from surface to depths of 30-40 cm. Within its home range, one individual has at least ten shelter burrows, connected by a network of well-used paths. Entrances of shelter burrows are always open and very visible by semicircular banks of rammed soil in front of them. In the wild during the non-breeding season, Greater Fat-tailed Jerboas are peaceful, and 2-3 individuals often forage 3-5 m apart. Breeding males are very aggressive and often fight.
Status and Conservation. Classified as Near Threatened on The IUCN Red List (as P. zhitkovi). The Greater Fat-tailed Jerboa has a small distribution and narrow habitat requirements.
Bibliography. Shenbrot et al. (2008).
description: Published as part of Don E. Wilson, Russell A. Mittermeier & Thomas E. Lacher, Jr, 2017, Dipodidae, pp. 81-100 in Handbook of the Mammals of the World – Volume 7 Rodents II, Barcelona :Lynx Edicions on pages 93-94, DOI: 10.5281/zenodo.6591722