Harpalus hospes ciscaucasicus Lutshn. (Coleoptera, Carabidae), a Ground Beetle Subspecies with a Widely Disjunctive Geographical Range

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Harpalus hospes Sturm, 1818 is a predominantly Eastern Mediterranean species with three parapatric subspecies connected by the populations with intermediate characteristics in the intergradation zones. The nominotypical subspecies ranges over Central and Southeastern Europe up to the Middle and Lower Volga areas and also occurs in Anatolia. In eastern Anatolia, it is replaced by the subspecies H. h. armenus (Daniel, 1904), which is also distributed in Transcaucasia. In the plains of the North Caucasus and the Volga region, the nominotypical subspecies is replaced by H. h. ciscaucasicus Lutshnik, 1921 with a wide intergradation zone. The geographical range of the latter subspecies is widely disjunctive and consists of two parts separated by the distance of about 2.5 thousand kilometers: one in the plains of the North Caucasus (Krasnodar and Stavropol territories, northern Daghestan), and the other, in the Russian Altai (Ob River valley) and Eastern Kazakhstan (Tayzhuzgen River valley). Previously this subspecies was considered as endemic to the North Caucasus, since a single record from Eastern Kazakhstan (Tayzhuzgen River valley) was a female collected there in 1946 and not assigned to a subspecies. New findings in the Tayzhuzgen and Ob valleys confirmed the constantness of this eastern isolate and revealed its formal belonging to H. h. ciscaucasicus since the males from this area possess all the distinctive features of this subspecies. The causes of this disjunction are not clear but seem to be connected with dramatic changes of the climate during Pleistocene-Holocene. The lectotypes of Harpalus sturmii Dejean, 1829 and H. h. ciscaucasicus Lutshnik, 1921 are designated.