Abstract

The main goal of the present paper is to define the kozlovi-species group of the genus Trechus Clairville, 1806, one of the most species-rich groups of Chinese Trechus and to describe new species of this group from two neighboring areas in Sichuan Province. Description of species groups for Chinese Trechus is a way to get a more consistent view of the taxonomy of this extremely diverse genus. The kozlovi group includes many described species, which are widespread in Qinghai, Gansu and Sichuan provinces. In turn, the group can be split into several subgroups each embracing close allopatric relatives but much more material from various areas of China is required for such detailed classification. In the present work, we describe 9 new Trechus species belonging to this group, all collected in central and southern Sichuan, China: T. suopoensis sp. n. and T. gemaensis sp. n., both from the northern slopes of Mount Gema, E of Danba City, T. bianericus sp. n. and T. maoniu sp. n., both from the nortwestern slopes of the mountain massif located south of Bianer Village, WNW of Danba City, T. shangensis sp. n., T. mengensis sp. n., both from the upper valley of the small river located WSW of the village of Shangmeng, NW of Lixian City, T. cuspis sp. n. from the southern slope of Mount “5200” NW of Lixian City, three latter species from the left bank of the Zagunao River, T. qunlaishanicus sp. n. from the Qunlaishan mountains on the right bank of the Zagunao River and T. chiguguanensis sp.n. from the Chiguguan Pass.