First data on the Hirudinea fauna of lotic ecosystems of the Khanty-Mansi Autonomous Area (Russia).

Hirudinea, a small and ecologically important group of aquatic organisms, is poorly studied in northern Eurasia. In this study, we demyth the idea of the faunistic poverty of this region and present the first findings of rheophilic leeches from the Khanty-Mansi Autonomous Area, Russia. Investigation of 25 rivers (Severnaya Sosva, Ob, Konda-Irtysh, and Bolshoi Yugan river basins) resulted in finding 10 leech species with parasitic and non-parasitic life strategies. These species belong to two orders (Rhynchobdellida and Arhynchobdellida), three families (Glossiphoniidae, Piscicolidae, and Erpobdellidae) and six genera (Alboglossiphonia, Glossiphonia, Helobdella, Hemiclepsis, Piscicola, and Erpobdella). Five species, A.hyalina, G.verrucata, E.monostriata, E.vilnensis, and potentially new morphological species of piscine leeches Piscicola sp., have been discovered for the first time in Western Siberia. Data on species diversity of rheophilic leeches include the exact systematic position for all leech taxa. Each species from the list is supplemented with information about its geographical distribution.

The present state of the leech fauna (Annelida, Hirudinea) in the Upper Irtysh cascade of water reservoirs.

Hirudinea is a small and ecologically important group of aquatic organisms. However, up to date, the leech fauna of Kazakhstan is poorly studied. The presence of large under-collected areas, such as the Upper Irtysh basin, makes biodiversity studies concerning these invertebrates from Kazakhstan relevant. In this paper, the latest information on species diversity of the freshwater hirudofauna of the Upper Irtysh cascade of water reservoirs, the Kazakhstan part of Irtysh River, is presented. It includes 10 free-living and parasitic species, of which 7 and 9 inhabit the Shulbinsk and the Bukhtarma reservoirs, respectively. These species belong to 2 orders, 3 families and 6 genera. The faunal list highlights four potentially new morphological species (Alboglossiphonia sp., Erpobdella sp., Piscicola sp. 1 and Piscicola sp. 2). Besides them, another three species Erpobdella vilnensis, Helobdella stagnalis and Theromyzon tessulatum recorded for the first time in the area. The exact systematic position is stated for all leech taxa. Each species from the list accompanied with information on taxonomic synonymy, data on its geographic distribution, and brief summary of morphological and ecological characteristics.

The first data on species diversity of leeches (Hirudinea) in the Irtysh River Basin, East Kazakhstan.

The Irtysh River is one of the major waterways of the Republic of Kazakhstan. The river originates in the territory of Mongolia and China, flows through the East Kazakhstan and falls into the Ob River in the Western Siberia of Russia. The Kazakhstan section of the river, with length of 1698 km and water resources about 43.8 km3 (Dyusebaeva 2012), is situated on the border of the West Siberian Plain, the Altai Mountains and the Kazakh Uplands. As the river crosses various natural zones, characteristics of its hydrological regime is very diverse. In the south, in the area of Ust-Kamenogorsk, the valley of the Irtysh extends. In the upper reaches up to the city of Semey (formerly Semipalatinsk), the river is surrounded by plain and mountain landscapes. Downstream from Semey, the Irtysh enters the West Siberian Plain and flows to north-west through dry steppes. The riverbed is unstable: sometimes it is very tortuous, sometimes it is broken into branches, and, there are a lot of sand spits. The hydrological level of the Kazakhstan part of the Irtysh River is regulated with the cascade of storage reservoirs near the towns Bukhtarma, Ust-Kamenogorsk and Shulbinsk.