[A revision of chiggers in the vulgaris group (Trombiculidae: Neotrombicula)]

A revision of chigger mites species, being closely related to Neotrombicula vulgaris (Schluger, 1955), is given. 2 new species are described: N. aideriensis sp. n. from Western Kopetdagh and N. macrovulgaris sp. n. from Western Caucasus. N. aideriensis sp. n. differs from all other species of the vulgaris group by presence of single barb on the lateral seta of palpal tibia in most specimens. This species differs also from N. vulgaris by lesser width of scutum, shorter setae of scutum and idiosoma and by longer legs. N. macrovulgaris sp. n. differs from all other species of the vulgaris group by longer legs, more numerous idiosomal setae and by larger scutum. N. vulgaris is recorded for the first time in Bulgaria, Turkmenistan (western Kopet-Dag) and Krasnodar Territory, N. baschkirica Kudryashova, 1998--in Chuvashia, Kirov Province, Komi Republic and Tyumen' Province, N. kharadovi Kudryashova, 1998--in Russia (Altai Territory) and in Karaganda Province (Kazakhstan). The latter species is reported from several new hosts. Variation of morphometric parameters in the vulgaris group are investigated by the methods of multivariate analysis, the pattern of correlations between them is shown. A complex of diagnostic features in the group is revised. Discriminant functions produced by the computer program DIADIS (A. L. Lobanov, ZI RAS) allows to determine confidently representatives of the vulgaris group. Ecogeographical component of intraspecific variability and character variance at the specific level is revealed in vulgaris group. N. macrovulgaris characterized by the largest scutum, numerous setae and long legs was found in the most rigorous, cold and damp climate (alpine zone of western Caucasus). On the other hand, N. kharadovi, which have the most fine scutum and shortest setae, inhabits rather dry and warm Middle Asia and neighbouring territories. The sample of N. vulgaris collected in the steppe part of Stavropol' Territory differed from the material collected in mountain forests of Western Caucasus by low values of the most part of measurements. N. kharadovi samples from plains of Middle Asia differed from samples of this species collected in western Pamirs, central Kazakhstan and Altay Territory by more fine scutum and shorter setae.