Archive

A combination of qualitative and dimensional characters has enabled the identification of Dermacentor species from Central Asia on their larval phase. Shape of auricles and lateral expansions of gnathosoma, structure of palps, tarsus, absolute sizes of gnathosomal organs and idiosomal setae and their ratio are used for differential diagnostics. Specific differential nature of characters is determined on larvae recovered from laboratory cultures and is approbated on material from nature. Differences in some variable dimensional characters in species have been revealed. The possibility of identification species on their larval phase has widened the picture of D. montanus and D. pavlovskyi distribution.

The midgut epithelial cells of newly emerged rat fleas demonstrate some pronounced differences from those of regularly-feeding animals (short and rear microvilli, less extensive basal labyrinth, poor developed rough endoplasmic reticulum and numerous cytoplasmic vacuoles). Similar cells can be found in 7 — day-old fleas never fed after emergence from pupa. The ultrastructure of the cells is alterated gradually in connection with blood meals and achieves a final "imaginal" structure after 3 days of regular feeding. Thus, long digestive cycle of newly emerged fleas may be explained by incomplete differentiation of midgut epithelium. The implication of these results are discussed and compared to similar ultrastructural events in hematophagous Diptera.

Methods of qualitative evaluation of informative rate of characters, their reactivity and availability for measuring are suggested. Analysis of a number of characters of two species of mosquitoes has shown that pupal mass index is most suitable as a morphological indicator.

The fauna of species of bloodsucking midges and their relationship in the zones of exploitation of Kremenchug and Dneprodzerzhinsk water reservoirs were studied 2, 17 and 20 years after their flooding. The analysis of the effect of hydroconstruction on the developmental conditions of midges was done.

In the south of East Transbaikalia (the village of Kubukhai, Onon district, Chita region) from June to August 1979 16 species of the genus Culicoides were captured with a light-trap NH-6 (Japan) as compared to the only four species collected on a human bait. Fauna of the midges of the area investigated consisted mainly of the species typical for the steppe zone of Siberia. Rather many specimens of C. expaliens, C. toyamaruae and C. gluchovae, relatively recently found in small number on the territory of the USSR, were collected in the above area.

A survey of literature on modelling cutaneous leishmaniasis of man (common and metastatic) on some lines of mice, guinea pigs, golden hamsters infected with different species of Leishmania is given. Merits and demerits of each described model are pointed out.

Ultrastructure and hystochemistry of penetration glands of oncospheres of some cestodes belonging to the families Dilepididae and Hymenolepididae, which use aquatic invertebrates as intermediate hosts, were studied. Electron microscopy studies of penetration glands of oncospheres of Trichocephaloides megalocephala, Microsomacanthus microskrjabini, Tschertkovilepis krabbei and Wardium pacificum have shown that they are multinuclear symplast with cytoplasmatic processes organized as ducts of mucus-secreting cells. There are two types of ducts which differ in size and localisation. Secretion of glands excreted through large ducts opening near embryonal hook can function during the migration period of oncospheres as substrate possessing adhesive and litic properties. Numerous smaller ducts on the surface of oncospheres can provide simultaneous excretion of substances possessing protective properties against macrophagal reaction of the host at the initial stages of larvogenesis. Hystochemical PAS staining of penetration glands of 19 species of oncospheres has shown that there are three possible ways of distribution of polysaccharides in these structures: 1) only neutral, 2) only acid, 3) neutral and acid simultaneously. The obtained data suggest that n some cases neutral polysaccharides are only intermediate links in the synthesis of acid mucoolysaccharides.

The problems of ecology and parasitism of mermithids of the genus Pheromermis developing in larvae of gad flies are considered. The description of Ph. rubzovi, some additions to described earlier Ph. vernalis Rubz., Andr. and Ph. zaamini Gaph., Kad., Norm. with discussion of variability of some characters, which are used in diagnostics of nematodes, are given.

A vast distribution area of Ixodes persulcatus is characterized by a definite comparatively small number of possible types of spatial structure of populations. Different regions (regional complexes of populations) are characterized by a definite number of such population types, from 1 — 2 under pessimal to 7 — 8 under optimum conditions.

10 species of fleas, Amphalius runatus, Amalaraeus dissimilis, Megabotris calcarifer, M. rectangulatus, M. advenarius advenarius, Ctenophyllus armatus, Amphipsylla marikouskii, Doratopsylla birulai, Catallagia dacenkoi, C. ioffi, are recorded from 10 species of small mammals from mountain regions of the southern part of Taimir. The greatest specific variety was observed in damp habitats while the least one in leafy ihin forests.

It was shown by means of microcrioscopical method that Acetabulastoma hyperboreum hyperboreum is an osmoconformer. Salinity tolerance range of ectoparasitic ostracod is wider when it is in contact with Gammarus oceanicus. Experimental observations corroborated the contact way of A. h. hyperboreum spreading.

A new method of obtaining promastigotes of Leishmania from reptiles has been worked out, the use of peripheral blood of these animals forming the basis of it. The new method considerably facilitates the diagnostics of leishmaniasis of reptiles, obtaining promastigotes of Leishmania for investigations, provides greater sterility of the sample, saves time of the investigator, preserves life of reptiles, that is important nowadays from the point of view of preservation of animal world, and makes possible long observations on infected reptiles.

Orthogonal nervous system of the parasitic turbellaria Anoplodium mediale is formed by cerebral ganglion, three pairs of longitudinal nerve stems, two transverse commisures, pharyngeal nerve ring and submuscular nerve plexus. It may serve as an example of centralisation which should be regarded as a trend in perfection of the nervous system of Platods.

A new species, Tetraonchus kifai sp. n., is described. The species was found on gills of Oncorhynchus gorbuscha (Walbaum), which enters the spawning rivers of the Amur basin.

Data on the activity of aminotransferases in haemolymph of Viviparus viviparus, Lymnaea stagnalis and Planorbarius purpura infected with parthenites of trematodes of different species and free of infection are compared. Specific, biological and sexual (in infected V. viviparus) variability of activity of alanineaminotransferase (ALAT) and asparate-aminotransferase (ASAT) was found out. Females of V. viviparus infected with parthenites of trematodes demonstrate a decrease in ASAT activity.

A new species of acanthocephals, Echinorhynchus sebastolobi sp. n. is described. The parasite was recorded in the intestine of one of 6 investigated specimens of Sebastolobus alascanus from the Okhotsk Sea.

Summary is absent.

Summary is absent.

Summary is absent.