Khobrakova L.T. 2017. [The ground beetles (Coleoptera, Carabidae) in the steppes of the East Sayan mountains, Russia] // Euroasian Entomological Journal. Vol.16. No.6: 501–512 [in Russian, with English summary].
Institute of General and Experimental Biology, Siberian Branch, Russian Academy of Sciences, Sakhjanovoj str. 6, Ulan-Ude 670047 Russia.
ABSTRACT. As a result of research confined to basins and mountain slopes, two main groups of steppe faunas of the ground beetles of the Eastern Sayan have been identified. Their spatial distribution in the basins obeys the altitude-belt distribution, and on the mountain slopes special steppe complexes (uburs) are formed, the distribution of which has a local character. The basins of the river Oka are dominated by steppe species (e.g. Cicindela coerulea nitida, Poecilus fortipes, Amara hanhaica, Curtonotus fodinae, Harpalus heyrovskyi, H. calceatus, H. tichonis, H. pusillus, H. amariformis, H. brevicornis and Cymindis binotata) characteristic of Transbaikalia and Mongolia. Mountainous steppe slopes are inhabited by mountain-steppe South Siberian species (Carabus spasskianus, Amara katajewi and Curtonotus tumidus tunkinensis), along with Dauro-Mongolian species, which can penetrate into the mountain taiga by the composition of forest-steppe complexes. Analysis of the faunistic relations of the localities revealed two high-altitude groups of ground beetles. In the lower belt of the forest-steppe (1300–1400 m) the largest species diversity (11) is in the genus Harpalus (11 species); in the upper belt (1500–1800 m), the species diversity increases, the largest diversities being in the genera Harpalus (9 spp.), Amara (7 spp.) and Curtonotus (4 spp.). The fragmented steppes in the mountains of the Eastern Sayan are considered relicts of the Pleistocene steppes of the Dauro-Mongolian type, which were widely distributed to the extreme north-east of Asia. The modern formation of steppe faunas of ground beetles of the Oka upland is associated with historical climate and landscape changes in the Pleistocene – Holocene, when the territory of the Eastern Sayan was subjected to semicircular and mountain-valley glaciations. Probably the steppe species of ground beetles penetrated to the Central Sayan plateau from Mongolia along the Khubsugul and Mondy inter-mountain hollows, and probably the autochthonous steppe fauna of ground beetles, characteristic of Southern Siberia, was formed at the same time on the mountainous southern slopes.
KEY WORDS: ground beetles, mountain steppes, East Sayan Mountains.