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The paper gives data on the fauna of chigger mites (Thrombiculinae), the ectoparasites of small mammals in Mongolia. The ecological and geographic analysis could reveal the major abiotic and biotic determinants of the spread of the chigger mites and make a map of their potential area.

The paper analyses the results of a survey of 37 Russian biosphere reserves using questionnaires concerning the presence of alien species of mammals, their pathways of penetration, and their impacts on protected ecosystems. The penetration of alien mammals into terrestrial ecosystems of Russia is extensive, both in places with maximum human environmental impact (inhabited areas and agricultural lands) and in biosphere reserves with minimal human impact. There are 62 mammal species registered as alien in Russian ecosystems and they account for 22% of the terrestrial mammal fauna of Russia. The percentage of alien species in biosphere reserves is 32.6% at most. In most regions, Castor fiber, Ondatra zibethicus, Nyctereutes procyonoides, Canis familiaris, Neovison vison and Sus scrofa are very dangerous, and both Castor fiber and Sus scrofa can have environment-forming impacts., (© 2008 ISZS, Blackwell Publishing and IOZ/CAS.)

We assessed the diversity of rodent communities in the deserts of Russia, Kazakhstan, and Central Asia using geographic information system technology. There are 66 species of rodents, belonging to eight faunistic complexes, inhabiting this area. We discuss the geographical changes occurring in taxonomic and zoogeographic diversity at both species and community levels. Communities of gerbils and jerboas dominate in the Turan Desert region (66% of the area). Steppe communities of susliks penetrate the deserts from the north. Farming in deserts causes the replacement of native rodent communities with mouse communities or completely eradicates rodents in their main habitats.

The history of studies of the great gerbil range was analyzed and position of the range boundaries was made more precise on the basis of the published data, museum collections, various natural maps, and authors' field observations. A scheme of the range regionalization is presented, in which three regional complexes of autonomous population groups are distinguished: Djungarian, Central Gobi, and East Gobi-Alashan'. Five autonomous population groups have also been isolated, which are located to the north of the main range: Shargin Gobi (?), Beger-nur, Orok-nur, Bulgan, and Bayan-dov. Regions with most favorable conditions for the great gerbil colonies were also shown.

The distribution of the great gerbil (Rh. opimus) in China was analyzed on the basis of published data, museum collections, natural maps, and authors' field observations. A preliminary scheme was plotted for range regionalization, in which three parts have been isolated or, according to classification of Dubrovskiĭ and Kucheruk (1971), three regional complexes of autonomous groups of populations: Dzungarian, Beishanian and Alashanian. West of the main area of the great gerbil distribution, an isolated colony is located in the Ili River valley, connected with the Kazakhstan portion of the range (Ili regional complex of autonomous groups of populations). Additional field observations are required for more detailed description of the great gerbil range.

The diversity of rodents is considered at various taxonomic levels within the limits of the Asian ecological transect, which crosses Asia from the Taimyr Peninsula in the north to the southern coast of Indostan and embraces territories of seven countries: Russia, Kazakhstan, Kyrgyzstan, Mongolia, China, Nepal, and India. The highest diversity of rodents is observed in the south of West Siberia and in mountains of Middle Asia. The least number of all taxa was noted in the Taimyr Peninsula and in the Tibet region.

Eleven virus strains were isolated from ticks Hyalomma asiaticum asiaticum Schulce et Schlottke, 1929, and Hyalomma plumbeum plumbeum Panzer, 1796,collected in 1971-1974 in desert regions of the Uzbee S.S.R. and the Turkmen S.S.R. According to CF test the strains were closely related to each other and not antigenically connected with viruses from antigenic groups A, B, California, CHF-Congo, Bakau, Bunyamwera, Gajam, Kaisodi, Qalyub, Kemerovo, Quaranfil, Simbu, Turlock, Hughes, Uukuniemi, Tete and 21 ungrouped viruses isolated from ticks. The virus was named "Tamdy" after the place of isolation of a prototype strain LEIV-1308 Uz. The virus does not agglutinate goose erythrocytes, it is pathogenic for suckling mice and 3 weeks old mice by intracerebral infection. Replication of a virus with CPE in cell cultures--L, Rh, A1--and without CPE--in pig embryo kidney cell cultures--was demonstrated. According to ultrafiltration and electron microscope data the size of the virus is about 90 nm. It is rather sensitive to lipid solvents and is an RNA-virus. Morphologically the virus resembles the Bunyaviridae.

Trypanosomes in the subgenera Herpetosoma, Schizotrypanom and Megatrypanum were found in 31 small mammals representing nine species of the orders Rodentia, Insectivora and Chiroptera in Iran.

In the summer 1976, natural foci of zoonotic cutaneous leishmaniasis were discovered by the authors on the territory of the Mongolian People's Republic. In 1976-1983 the integrated research of these foci was conducted and maps of a structure of the geographical range of the pathogen were compiled taking into account the peculiarities of distribution of its carriers and vectors. Great gerbils are the only identified vertebrate hosts of Leishmania and their infection rate comes up to 100% in single foci. Three species of sandflies belonging to subgenus Paraphlebotomus, Ph. andrejevi, Ph. mongolensis and Ph. alexandri, are vectors of the pathogen in foci. The most common of them in burrows of gerbils is Ph. andrejevi. It was established by genetic and biochemical methods that two variants of Leishmania major may circulate simultaneously in individual natural foci in the MPR, but both of them have a low virulence and are not dangerous for man.

Three identical strains of an arbovirus were isolated from 475 Ornithodoros papillipes ticks collected in June, 1972, in burrows of the great gerbil (Rhombomys opimus Licht., 1882) in the environs of Beshkent, Karshinsk steppe, Uzbek S.S.R. The isolate was found to range among flaviviruses. Complement-fixation, agar diffusion precipitation and neutralization tests is tissue culture and mice indicated a one-way antigenic relationship between the isolate and West Nile virus. However, the pattern of differences between them made it possible to consider the isolated agent as a new virus, "Karshi" virus. The results of electron microscopic studies of this virus are presented.

Zoonotic cutaneous leishmaniasis is still a public health problem in Central Asia. To control the outbreaks, different control measures are required in different regions and comprehensive information is required about natural foci.The term landsaft, used by Soviet geographers to denote particular geographical regions, is defined and this concept is used in examining the natural focality of zoonotic cutaneous leishmaniasis in the south of the Turkmen SSR.The main reservoir species in this area was Rhombomys opimus, and the disease was transmitted mainly by Sergentomyia arpaklensis, Phlebotomus papatasi, and Phlebotomus caucasicus. The burrows of R. opimus were the main shelters and breeding places of the sandflies, but infection was not transmitted equally in all burrows.It was known that the distribution of sandflies within the burrows was influenced by the humidity in the different parts of the burrow and a survey showed that the highest rate of infection of gerbils occurred in the burrows in those areas with the highest subsoil moisture content.Studies of the prevalence of zoonotic cutaneous leishmaniasis among people in the settlements of the Murghab oasis showed that the years with the highest infection rate were also years with slightly higher rainfall and lower air temperatures in this area.