There are three species (Corbet 1978, 1984; Corbet and Hill 1991; Csorba 1993; Holden in Wilson and Reeder 1993; Kurtonur and Ozkan 1991; Rossolimo 1976a, 1976b):
Head and body length is 61-120 mm, tail length is 53 - 94 mm, and weight is 21-56 grams (Kurtonur and Ozkan 1991; Rossolimo 1976a, 1976b; Van Den Brink 1968). The general coloration of the upper parts is a closely mixed combination of ochraceous and gray. The underparts, insides of the limbs, and feet are white. There is a sharply defined line of demarcation between the upper and lower parts. Unlike other dormice, which have rather bushy tails, Myomimus has a thinly haired, mouselike tail covered with short, white hairs. Females have seven pairs of mammae, suggesting a large number of offspring (Niethammer in Grzimek 1990).
Remarkably little is known about this genus. Niethammer (in Grzimek 1990) noted that it was initially described from Turkmenistan in 1924 and was not discovered farther west until later. Ognev (1963) indicated that Myomimus is the only myoxid that is not specialized for arboreal life. Van Den Brink (1968) stated that Myomimus seems to live on and under the ground. Kurtonur and Ozkan (1991) found it to be relatively widespread in Thrace, where it prefers open country with clusters of trees and bushes, such as the edges of grain fields, orchards, gardens, and riverbanks. Most specimens were trapped on trees, especially mulberry, but none were taken in forests. The presence of juveniles and subadults in June and August suggests a breeding period from April to June in Thrace. Pucek (1989) designated Myomimus as one of the "top ten endangered rodents in Europe." Suitable habitat evidently is very limited and declining. The IUCN now classifies M. setzeri as endangered, noting that there already has been at least a 50 percent decline in the past 10 years. M. personatus and M. roachi are classed as vulnerable.
Information taken from: Nowak, R.M. (Ed.). Walker's Mammals of the World. 6th Edition. The John Hopkins University Press. Baltimore and London, 1999.