The ground beetles of the subgenus Caucasoharpalus Kataev, 2023, genus Harpalus Latreille, 1802 (Coleoptera: Carabidae)

A taxonomic review of the Caucasoharpalus Kataev, 2023, the only subgenus of the genus Harpalus Latreille, 1802 (Coleoptera: Carabidae), endemic to the Caucasus, is presented. The subgenus includes three species, one of which, H. belousovi sp. n., is newly described from the Svaneti and Racha-Lechkhumi regions (Georgia). This species is parapatric with H. aeneipennis (Faldermann, 1836) and forms two subspecies: the nominotypical one (the western part of the Svaneti Mountain Range) and H. b. conterminus subsp. n. (the southern slopes of the Main Caucasus Range, the eastern Svaneti Mountain Range and the Lechkhumi Mountain Range). The third species, Harpalus chrysopus Reitter, 1887 is treated as polytypical, with six subspecies, two of which are newly described, while the rest are presented in a new interpretation: H. ch. chrysopus, H. ch. retowskianus Reitter, 1887, stat. n., H. ch. abasinus Rost, 1891, H. ch. contumax Lutshnik, 1933, H. ch. chkhaltensis subsp. n., and H. ch. kodorensis subsp. n. The latter two subspecies are described from the Abkhazian and Kodor ranges, respectively. A key to species and subspecies is provided. Individual, altitudinal and geographical variability of colouration and structural characters of species and subspecies is discussed. It was found that leg colouration and pronotum shape of H. chrysopus depend significantly on altitude. A possible scenario for the main moments of formation and differentiation of the subgenus is also discussed. The following synonymy is proposed: H. ch. retowskianus Reitter, 1887 = H. dinniki Lutshnik, 1933, syn. n. The lectotypes are designated for H. chrysopus Reitter, 1887 and H. abasinus Rost, 1891.