The Russian tortoise is a small tortoise species, with a size range of 13–25 cm (5–10 in). Females grow slightly larger (15–25 cm [6–10 in]) to accommodate more eggs. Males average 13–20 cm (5–8 in).
Russian tortoises are sexually dimorphic. Males tend to have longer tails generally tucked to the side; females have a short, fat tail. The male has a slit-shaped vent (cloaca) near the tip of its tail; the female has an asterisk-shaped vent (cloaca). Russian tortoises have four toes. Coloration varies, but the shell is usually a ruddy brown or black, fading to yellow between the scutes, and the body is straw-yellow and brown.
The male Russian tortoise courts a female through head bobbing, circling, and biting her forelegs. When she submits, he mounts her from behind, making high-pitched squeaking noises during mating.
This species is traditionally placed in Testudo. Due to distinctly different morphological characteristics, the monotypicgenusAgrionemys was proposed for it in 1966. Today, Agrionemys horsfieldii is currently being accepted.DNA sequence analysis generally concurs, but not too robustly so. Some sources also list three separate subspecies of Russian tortoise, but they are not widely accepted by taxonomists:
A. h. horsfieldii (Gray, 1844) – Afghanistan/Pakistan and southern Central Asia
A. h. kazachstanica Chkhikvadze, 1988 – Kazakhstan/Karakalpakhstan
A. h. rustamovi Chkhikvadze, Amiranschwili & Atajew, 1990 – southwestern Turkmenistan
da Nóbrega Alves, Rômulo Romeu; da Silva Vieira; Washington Luiz & Gomes Santana, Gindomar (2008): Reptiles used in traditional folk medicine: conservation implications. Biodiversity and Conservation17(8): 2037–2049. doi:10.1007/s10531-007-9305-0 (HTML abstract, PDF first page)
Fritz, Uwe; Kiroký, Pavel; Kami, Hajigholi & Wink, Michael (2005): Environmentally caused dwarfism or a valid species - Is Testudo weissingeri Bour, 1996 a distinct evolutionary lineage? New evidence from mitochondrial and nuclear genomic markers. Molecular Phylogenetics and Evolution37: 389–401. doi:10.1016/j.ympev.2005.03.007
Khozatsky, L.I. & Mlynarski, M. (1966): Agrionemys - nouveau genre de tortues terrestres (Testudinidae). Bulletin de l'Académie Polonaise des Sciences II - Série des Sciences Biologiques2: 123-125.