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.

Amazing Discoveries of Benthic Fauna from the Abyssal Zone of Lake Baikal.

Lake Baikal is a natural laboratory for the study of species diversity and evolution, as a unique freshwater ecosystem meeting the all of the main criteria of the World Heritage Convention. However, despite many years of research, the true biodiversity of the lake is clearly insufficiently studied, especially that of deep-water benthic sessile organisms. For the first time, plastic waste was raised from depths of 110 to 190 m of Lake Baikal. The aim of this study was to examine the biological community inhabiting the plastic substrate using morphological and molecular genetic analysis. Fragments of plastic packaging materials were densely populated: bryozoans, leeches and their cocoons, capsules of gastropod eggs, and turbellaria cocoons were found. All the data obtained as a result of an analysis of the nucleotide sequences of the standard bar-coding fragment of the mitochondrial genome turned out to be unique. Our results demonstrate the prospects for conducting comprehensive studies of artificial substrates to determine the true biodiversity of benthos in the abyssal zone of Lake Baikal.

New data on species diversity of Annelida (Oligochaeta, Hirudinea) in the Kharbey lakes system, Bolshezemelskaya tundra (Russia).

One of the features of the tundra zone is the diversity of freshwater bodies, where, among benthic invertebrates, representatives of Annelida are the most significant component in terms of ecological and species diversity. The oligochaete and leech faunas have previously been studied in two of the three largest lake ecosystems of the Bolshezemelskaya tundra (the Vashutkiny Lakes system, Lake Ambarty and some other lakes in the Korotaikha River basin). This article provides current data on annelid fauna from the third lake ecosystem in the region, Kharbey Lakes and adjacent water bodies. The annelid fauna includes 68 species, including 51 oligochaete species, and 17 species of leeches. For each species, we give information on currently recognised classification, taxonomic synonymy, geographical distribution, findings of the species within the Russian tundra, and brief ecological characteristics.

New information on the distribution pattern of Acanthobdella peledina (Annelida, Acanthobdellida) in Eastern Siberia.

The Acanthobdellida is a group of annelid parasites of fish, which are restricted to subarctic parts of the Northern Hemisphere. These ancient worms arouse the interest of the scientific world due to their mosaic combination of (1) primitive oligochaetous characters (e.g. the presence of setae on the very anterior segments, a lateral nerve system and a metameric coelomic cavity around the intestinal canal) and (2) evolutionarily advanced hirudinean ecological and morphological features (e.g. suckers and parasitic lifestyle), attesting to their intermediate role between Oligochaeta and Euhirudinea (i.e. leeches with setae).

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.

Annotated checklist of the leech species diversity in the Maloe More Strait of Lake Baikal, Russia.

In this paper, the very first checklist of the freshwater leeches of Maloe More Strait, a special part of Lake Baikal, is presented. It includes 14 free-living and parasitic species, of which four species belong to endemic Baikal genera - two species from Baicalobdella and one species each from Baicaloclepsis and Codonobdella. The checklist highlights six potentially new morphological species recorded for the first time in the area. The exact systematic position is stated for all leech species. Each species from the list is provided with information on taxonomic synonymy, data on its geographic distribution, and ecological characteristics. New species records are additionally provided with brief morphological characteristics and photos of their external morphology.

Genetic diversity of freshwater leeches in Lake Gusinoe (eastern Siberia, Russia).

The study of leeches from Lake Gusinoe and its adjacent area offered us the possibility to determine species diversity. As a result, an updated species list of the Gusinoe Hirudinea fauna (Annelida, Clitellata) has been compiled. There are two orders and three families of leeches in the Gusinoe area: order Rhynchobdellida (families Glossiphoniidae and Piscicolidae) and order Arhynchobdellida (family Erpobdellidae). In total, 6 leech species belonging to 6 genera have been identified. Of these, 3 taxa belonging to the family Glossiphoniidae (Alboglossiphonia heteroclita f. papillosa, Hemiclepsis marginata, and Helobdella stagnalis) and representatives of 3 unidentified species (Glossiphonia sp., Piscicola sp., and Erpobdella sp.) have been recorded. The checklist gives a contemporary overview of the species composition of leeches and information on their hosts or substrates. The validity of morphological identification of each taxon has been verified by phylogenetic approach with a molecular marker adopted for a DNA barcoding of most invertebrates.

Mass leech infestation of sculpin fish in Lake Baikal, with clarification of disease-prone species and parasite taxonomy.

Sculpin fish bdellosis in Lake Baikal is caused by leech ectoparasites, which are identified as belonging to the genus Baicalobdella. In addition to Cottocomephorus grewinkii, eight sculpin hosts for Baicalobdella are newly recorded: Paracottus knerii (Cottocomephorinae), and Abyssocottus korotneffi, Asprocottus platycephalus, Batrachocottus baicalensis, Batrachocottus multiradiatus, Cyphocottus megalops, Limnocottus griseus and Procottus major (Abyssocottinae). These host fishes are mass infected by Baicalobdella leeches (up to 75%) in different sites of Lake Baikal. Comparative morphological analysis of Baicalobdella infecting sculpin fishes vs. Baicalobdella torquata proper revealed nine distinctive features that allow confirming a separate systematic position and revalidating original name Baicalobdella cottidarum Dogiel, 1957.

New records of Lake Baikal leech fauna: species diversity and spatial distribution in Chivyrkuy Gulf.

The study of several Lake Baikal leech collections offered us the possibility to determine species diversity in the Chivyrkuy Gulf, the biggest one in the lake. As a result, the first information on the Chivyrkuy Hirudinea fauna (Annelida, Clitellata) has been revealed. There are two orders and four families of leeches in the Chivyrkuy Gulf: order Rhynchobdellida (families Glossiphoniidae and Piscicolidae) and order Arhynchobdellida (families Erpobdellidae and Haemopidae). In total, 22 leech species and 2 subspecies belonging to 11 genera were identified. Of these, 4 taxa belong to the family Glossiphoniidae (G. concolor, A. hyalina, A. heteroclita f. papillosa, and A. heteroclita f. striata) recorded in Baikal for the first time. Representatives of 8 unidentified species (Glossophinia sp., Baicaloclepsis sp., Baicalobdella sp., Piscicola sp. 1, Piscicola sp. 2, Erpobdella sp. 1, Erpobdella sp. 2, and Erpobdella sp. 3) have been also recorded. The checklist gives a contemporary overview of the species composition of leech parasites, their hosts, and distribution within the Chivyrkuy Gulf. The analysis of spatial distribution has shown that the leech species diversity is correlated with the biological productivity of the bay. The most diverse community of leech species is detected in the eutrophic zone of the lake.

Leech-like parasites (Clitellata, Acanthobdellida) infecting native and endemic eastern Siberian salmon fishes.

Salmonoid fish bdellosis is caused by leech-like ectoparasites in the monogenetic order Acanthobdellida. Although Acanthobdella species have been known to infect several threatened species in Eurasia, little is known about their ecology and epidemiology. In this paper, we report on the mass affection (up to 70.7%) of fish in lower course of the Chechuj River, a right tributary of the Lena and provide information on finding Acanthobdella peledina on two of six salmonoid fish species inhabiting there: lenok and grayling. New and more specific data on morphological peculiarities and feeding strategy were obtained. The ratio of body length to width in studied acanthobdellid collection is significantly less than one provided for the A. livanowi and the rest A. peledina from other water systems of Eurasia. Biology and lifestyle of the parasite population are revealed for the first time.