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All the specific and subspecific names of mosquitoes originally described from the territory of the former USSR since 1771 (when first names were given) to 1996 are presented. They belong to mosquitoes of 6 genera (Anopheles, Aedes, Coquillettidia, Culex, Culiseta, Toxorhynchites) and 13 subgenera. The annotated list includes 69 names of following categories: valid names (23), synonyms (38), nomina dubia (4), nomina oblitum (2), nomina nudum (2).

Six species of the genus Anopheles are recorded in the North of the Tien Shan. As far as an epidemiological situation in the region in question in gets worser, the factors determining links between people and mosquitoes, namely the food preference of different species of Anopheles, the frequency of actual mosquito attacks and the physiological age of mosquito females have been analysed. It is shown, that A. claviger and A. messeae are the most probable potential malaria vectors in mountain regions, and A. hyrcanus - in lower parts of the Tien Shan.

Within the boundaries of the former USSR, the northern part of the conformis group distribution is located. It spreads over the arid regions of the Trans-Caucasus, Pricaspijckaja lowland, Kazakhstan and Middle Asia. In this area 10 species and subspecies occur. They are mainly parasites of gerbillins. Unlike many other Siphonaptera the conformis fleas, when in the host's home, do not concentrate in the nest but inhabit the passages of burrow and food chambers throughout the year. On this reason the preimaginal development and existence of the adults take place not at the temperature of the habitable nest, which is heated by the host body, but at the temperature of the soil at a depth of burrow. The temperature threshold for preimaginal development of conformis fleas is reported to be 10-12°. Temperature below the threshold is fatal for all immature instars. On the contrary the imago can survive at free-zing temperature. The annual cycle of the conformis fleas is characterized by the presence of adults throughout the year. They breed in the warmer season and overwinter in the state of reproductive diapause. In this state the fleas are able to attack the host and to feed but do not deposit eggs. In the north deserts the reproduction begins at the early April and terminates at the early September. Southern, the reproductive period is longer. Futhermore, the complite interruption of the reproduction in the autumn-winter time may be absent as it was observed in X. gerbilli gerbilli and X. hirtipes in the south of the Middle Asia. On the other hand it is noted that in southern deserts the rate of oviposition falls in the most hot time. The number of generation per year in the conformis fleas varies from 2-3 in north deserts to 6-7 in south ones. The flea populations peak in late autumn when the insects cease to bread. The high abundance is maintained until springtime. After the diapause is ceased and the fleas begin breeding their abundace declines. In the late spring and early summer the emergence of adults begins and the populations increase. In a middle of summer the second fall takes place and then the fall is replaced by the autumnal peak. On their main hosts the conformis fleas prevail over all other species of Siphonaptera especially for warmer time when their quota among other fleas does not descend as a rule below 90% but more often it approaches to 100%. The fleas of this group and especially species parasitizing Rhombomys opimus are remarkable for the high level of their abundance. In the northern deserts in the periods of the most high abundance (late autumn, winter and early spring) the number of fleas per burrow occupied by family of Rh. opimus exceeds usually 1000 specimens and sometimes it can reach several thousands. In the southern deserts the abundance of the fleas is lower but the period of their active parasitizing is longer. In the species parasitizing Rh. opimus it is shown that in a complex burrow only some part of fleas has the possibility to feed regularly. In the spring and summer the percentage of fleas daily attacking the host varied from 17 to 86% and from 10 to 150 ectoparasites feed daily on one animal depending on the quantity of fleas and of hosts in the burrow. The number of attacking fleas is regulated by behavior of the hosts, which change the used parts of burrow when the fleas are crowded there.

This article continues the series of electronic microscopical investigations of tick attachment and host's inflammatory reaction in the attachment site. In all this works we used larvae of different Ixodid ticks but the same species of the host (white mouse), Ixodid species having different type of attachment. Dermacentor marginatus (Amosova, 1989a) is characterized by the supefhical penetration of mouthparts, the abundance of cement around them and on the surface of the hosts skin, the mouthparts of Hyalomma asiaticum are fully inserted and the superficial cement is minimal (Amosova, 1989b) and Ixodes ricinus has mouthparts inserted more deeply in the skin tissue of the host and the cement substance localised only on the surface of the skin at the 1st and 2nd days of feeding period. For this investigation we choose Haemaphysalis longicornis because it is known (see Kemp et al., 1982) that genus Haemaphysalis has the most superficial localization of the mouthparts in the attachment site. We have studied a fine structure of cement cone and the cement substance surrounding the mouthparts in the skin and have demonstrated that it is very similar to the Dermacentor marginatus cement structure. The pattern of cellular response is similar to D. marginatus lesion too.

138 Ixodes persulcatus and 140 I. ricinus ticks were collected by flagging in the Moscow region of Russia in April-September 1995. Borrelia burgdorferi infection rates of 171 (73 I. persulcatus and 98 I. ricinus) flat ticks were ascertained by both a dark-field microscopy and an enzyme-linked immunosorbent assay (ELISA). The ELISA is based on the use of "capture" monoclonai antibodies (mABs) to Osp A L12-9B4 (2D8) in combination with rabbit antisera to Osp A and B. This mAB reacts with B. burgdorferi sensu stricto well as B. garinii, it has no reactivity with B. afzelii (isolate Iper3, Russia). Dark-field examination showed 11% infected ticks. The Osp A antigen positivity rate was 12%. 87% concordance between the two assays was recorded. In this study we investigated homogenates of 94 (33 - I. persulcatus, 60 - I. ricinus and 1 hymph Ixodes sp.) engorged ixodid ticks removed from humans for the presence of B. burgdorferi by the ELISA. Osp A of B. burgdorferi was found in 18 (19%) of the ticks. Osp A was also found in 57 of 107 (53%) ixodid ticks collected on vegetation in the Moscow region. This group of ticks was not tested by a dark-field microscopy as they died shortly after being collected.

The study of the species group autumnalis in genus Neotrombicula is carried out. Composition of the group and diagnoses of species are changed, data on variability are reported. A new species, N. oculata sp. n., is described. The new species is similar to N. turkestanica Kudryashova, 1993 and differs from itby disproportionaly large eyes, a little more numerous setae of idiosoma (NDV = 66-78 against 58-69) and their lesser lengths (Dm = 41-46 against 45-49), a lesser width of scutum (AW = 71 against 76). One species, N. alexandrae Stekolnikov, 1993, is synonymized with N. delijani Kudryashova, 1977. For N. delijani and N. turkestanica new localities and new hosts are reported.

An effect of a heat shock on a fatty acid composition of membrane and reserve lipids of plerocercoids of three cestode species, Ligula intestinalis, Schistocephalus solidus, Diphyllobothrium vogeli, was investigated. It has been detected a high level of saturation of lipids in the plerocercoids, that could be interpreted by a preadaptation of fatty acid spectra to thermal conditions of warm blooded hosts. It was shown that in a result of a short time action of high temperature the concentration of saturated fatty acids in the membrane lipids, especially stearic ones, was increased. The tendency of alteration of fatty acid spectra components was similar in representatives of the family Ligulidae and differed from that in D. vogeli (Diphyllobothriidae), i. e. a taxonomic nature of these difference was assumed.

Results of the seventy year long study of a species composition of trematode parasites in basins of the Dvina river, Mesen' river and Pechyora river are summed up. During this time the 50 trematode species were recorded in the first basin, 30 species - in the second basin and 36 species - in the third basin. The total number of trematode species recorded in the examined region is 56 species.

Summary is absent.

Summary is absent.