Abstract
The superorder Colobognatha is represented in the Caucasus by three genera and species, one each in the orders Polyzoniida, Platydesmida and Siphonocryptida. Hirudisoma roseum (Victor, 1839) (Hirudisomatidae, Polyzoniida) is especially widespread, ranging from S Russia, Abkhazia, Georgia (with a neotype designated and described from Kakhetia, E Georgia) and NW Azerbaijan to E Turkey, and also including H. ponticum (Lohmander, 1939) (junior subjective synonym, syn. nov.). Fioria hyrcana Golovatch, 1980 (Andrognathidae, Platydesmida) is endemic to the Hyrcanian parts of the Republic of Azerbaijan and NW Iran along the western and southern coasts of the Caspian Sea. Due to the finding of Hirudicryptus abchasicus sp. nov. (Siphonocryptidae, Siphonocryptida), from a single locality in Abkhazia, NW Caucasus, the order Siphonocryptida is new to the fauna of the region. A key to all four species of the trans-Palaearctic genus Hirudicryptus is given. All three Caucasian species of Colobognatha are described in due detail and abundantly illustrated, and their distributions mapped.