The Russian tortoise (Testudo horsfieldii), also commonly known as the Afghan tortoise, the Central Asian tortoise, Horsfield's tortoise, four-clawed tortoise, and the (Russian) steppe tortoise, is a threatened species of tortoise in the family Testudinidae. The species is endemic to Central Asia. Human activities in its native habitat contribute to its threatened status. Etymology Both the specific name, horsfieldii, and the common name "Horsfield's tortoise" are in honor of the American naturalist Thomas Horsfield. Systematics This species is traditionally placed in Testudo. Due to distinctly different morphological characteristics, the monotypic genus Agrionemys was proposed for it in 1966, and was accepted for several decades, although not unanimously. DNA sequence analysis generally concurred, but not too robustly so. However, in 2021, it was again reclassified in Testudo by the Turtle Taxonomy Working Group and the Reptile Database, with Agrionemys being relegated to a distinct subgenus that T. horsfieldii belonged to. The Turtle Taxonomy Working Group lists five separate subspecies of Russian tortoise, but they are not widely accepted by taxonomists: T. h. bogdanovi Chkhikvadze, 2008 – southern Krygystan, Tajikistan, Uzbekistan, Turkmenistan T. h. horsfieldii (Gray, 1844) – Afghanistan/Pakistan and southern Central Asia T. h. kazachstanica Chkhikvadze, 1988 – Kazakhstan/Karakalpakhstan T. h. kuznetzovi Chkhikvadze, Ataev, Shammakov & Zatoka, 2009 – northern Turkmenistan, southern Uzbekistan T. h. rustamovi Chkhikvadze, Amiranschwili & Atajew, 1990 – southwestern Turkmenistan Description The Russian tortoise is a small tortoise species, with a size range of . Females grow slightly larger () to accommodate eggs. Males average . Russian tortoises are sexually dimorphic. Males tend to have longer tails generally tucked to the side, and longer claws; females have a short, fat tail, with shorter claws than the males. 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 depending on the subspecies. 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. The species can spend as much as 9 months of the year in dormancy. Captivity Russian tortoises are popular pets. They can be kept indoors or outdoors, but outdoor tortoise enclosures generally require less equipment and upkeep,