Rodent the size of a squirrel. Adult weight of 600-800 g; length body 255-295, 75-100 tail, hind foot 60-68 mm; fingers limbs are long and thin. On the back of the longest limb second to fourth fingers at the front — the second and third. Claws up to 15 mm. Eight nipples, no cheek pouches (viewed 20 adults from Southern Balkhash).
Winter fur is long (up to 15-18 mm) fluffy, soft with a thick undercoat. Spin straw-yellow in color, with no clear weak spot. The summer fur is very rare, short and without underfur. Hair tight and snug against the skin. In summer fur guard hairs under a microscope look like flat, short needles, needle-like hedgehogs or porcupines. The structure of the winter hair the same, only they are longer and thinner.
The underparts are silvery white with a relatively soft and long (winter) silky hairs. Bushy tail, the bottom third of it in the main brown, and the rest — pure black, except for a light-colored fringing hair. Feet from the bottom completely covered with short thick hair. The outer edge of the rear foot a short fringe of stiff hairs. On hind feet along the outer toe, from its base, moving away for a few very long hairs in the form of a beam acting on 10-15 mm for the longest finger. Characteristic concentration of vibrissae on the ventral side of the body.
During the year, shedding occurs twice — in the spring and fall. According to the location and nature of the vibrissae molting clawed gopher resembles an ordinary squirrel. Moult a long one, which is due not only hodomsamogo slow process, but also non-simultaneous coverage of, the entire population of animals. The process of shedding longer in the southern areas where rodents than in northern ones. This is explained by the more rapid temperature amplitude of the seasonal range in the north of the animal.
Spring moult starts with the head, it is sent back, grabbing the back and sides, the last to fade the back of the back, legs and tail. In the autumn moult observed her back order. Molt in young adult fur is on the same order, on which there is the spring molt adults.
The process of spring moult tracked us on the big stuff. Observed that the summer fur grows to the final loss of the winter. Subject to abnormal shedding, when the winter wears fur sprouting up year, on the back exposing still preserved black underfur and animal acquires an unusual dark color with all kinds of holidays.
In exceptional cases, the spring moult in this animal can be very delayed, so individuals with obnoshennym winter fiber-
Autumn molt slower spring, which can be explained by a sudden change in temperature in the spring than in the fall. The duration of the period the clawed ground squirrel in the winter fur in northern habitats exceeds that in the south.
I clawed gophers noteworthy hairiness hind feet (6-12 mm) which is most clearly expressed in the winter, because in summer the hair wear out and burn some, getting a yellowish tint. Pubescence at the feet of the animal has an adaptive value as a tool for movement on the sand and extremely hot (70 °), or rather cold soil.
Besides the general hairiness, paws of the animal provided with a sort of elongated hair fringing his fingers. They help with the movements on granular soils, increasing the footprint of the foot. Changing of the seasons had not noticed. Foot support area is also increased due to the elongated toes and claws. It is interesting to point out that the ratio of the rear foot to the body length of a clawed ground squirrel 1: 4.
Molting clawed ground squirrel also has an adaptive value. Unlike the winter fur is expressed to a greater extent than in su-mospyaschih gophers.
Well marked geographical variation of sizes and colors clawed ground squirrel in complete violation of clinal variation. The darker color of fur and large body size and skull characteristic forms inhabiting the extreme south (Turkmenistan, Afghanistan) and northeast (Balkhash, Muyunkum) part of the range.
Very peculiar structure of the skull. According to the general configuration, it looks more like a skull protein than gophers. The width of the interorbital space more than 30% condylobasal length (a kind of ground squirrel Citellus 20-23%). Based on the measurements of 20 adults from Southern Balkhash, condo-basal skull length is 44-54, zygomatic width 31 — 38.5, interorbital space of 13-20, 25-28, occipital width, height 16-17,5 skull, nasal length Bone 20-21, length top row of molars 10-12, diastema 12 — 13 mm.
Field signs. Clawed ground squirrel is of the yellow ground squirrel and southern subspecies same monochrome sand-yellow fur. However, it is relatively easy to distinguish. Valkoobraznoe body clawed gopher more elongated with a sharply separate head, he has a very well developed limbs, especially the rear, so animal jumping moves, raising from the ground. Limbs snabzhenydlinnymi fingers, and soles of the feet and densely pubescent. Long tail is dark subapical band. When animal runs, he fluffs it, and at this time it can be clearly seen black spot signal. Coat undeveloped summer: hair short, rare and very coarse (bristly) winter it thick and fluffy. Unlike other squirrels clawed active year-round. Within days, he figures in the hottest hours of the day. Animal assumes the pose of "columns", often being on top of the dunes, or hiding under a <ronami shrubs. Voice — the chirping of magpies and a sharp monosyllabic whistle, published in the event of an alarm. Extremely cautious beast and very agile in their place of habitation. In nature, clawed ground squirrel rarely observed quietly zhiruyuschim or resting in burrows, but almost always — in rushing.