The detailed description of Atherix ibis larvae, including the structure of head capsule, anterior and posterior spiracles, and cuticular structure of the body is given. The larvae of Atherix, which were often mentioned as apneustic, are really amphipneustic ones. Similar characteristics of larvae in Athericidae and Tabanidae are discussed.
Chubareva L.A., Petrova N.A.
Karyotypes of 31 blackfly species of 19 genera from the northwestern region of Russia were studied based on squashed aceto-orsein preparations of polytene chromosomes of salivary larva glands, mitotic chromosomes of gonads and ganglia. A karyotype of Simulium reptans L. is described for the first time. New data on genome polymorphism of Cnepha fontinalis Radz., Simulium argyreatum Mg., and Archesimulium tuberosum Lund. are represented. Twenty species (64.5%) have 2n = 6 and three species (9.7%), 2n = 4. Seven species (22.6%) are characterized by genome polymorphism according to accessory B-chromosomes (2n = 6 + B); some species, by notable inversion polymorphism. Populations of two species (6.4%) are represented only by triploid females (3n = 9). In this region, the high level of the karyological species diversity in blackflies was found.
The average level of singing activity in males of different Ficedula hypoleuca phenotypes (n = 101) was similar. At the same time, their behavioral pattern was different. The metronome timing of 56 bachelor males (178 hours) was carried out. The average level of energy expenditures for each male in the daytime (without cost of thermoregulation) was calculated from the time budget using converting coefficients (Dolnik, 1980). The rate of energy expenditure was found to be higher in cryptically colored males (V-VII grades by Drost’ s scale) than in conspicuous ones (II-III grades) (2.5 x BMR and 2.1 x BMR, correspondingly) mainly due to the heavier time expenses for flight activities (12% against 7.8% in conspicuous males). The pattern of behavior in males with the color type IV was intermediate. The more expensive style of advertising behavior in cryptically colored birds compensate their less attractive appearance than that in dark-colored males.
Lyapkov S.M., Kornilova M.B., Severtsov A.S.
The long-term stationary studies of a Rana temporaria population and the determination of age according to annual layers in bone tissue showed that the proportion of males that bred for the first time at the age of 3 years was higher (55% of all the 3-year-old males) than that in females (26%). The mean age and survival rate was higher in females than in males. The body length in 3 year-old males and females did not differ, but from an age of 4 years the length of body in males was smaller than in females of the same age. The relatively small size of males from breeding ponds results from their lower (than in females) growth rate and the higher proportion of relatively young mature frogs among males. In breeding ponds, the absolute and relative values of the length of brachium, forearm, femur, tibia, foot, and of the 4
Gamasid mites inhabiting seven mass species of bracket fungi were studied. Among 26 species found, 8 species were mycetobionts (Ascidae, Ameroseiidae), 4 species, dendrobionts (Digamasellidae, Phytoseiidae), and the rest species were litter forms. The species diversity in perennial hard fungi was low (1-6 species); 99-100% of the total population were specialized mycetobionts (Hoploseius, Mycolaelaps, Ameroseius). In annual leathery bracket fungi, 11-14 species were recorded. Mycetobionts were represented by unspecialized forms (Lasioseius, Zerconopsis, Aceosejus); litter forms prevailed.
The studies of hematologic features of amphibians along the gradient of anthropogenic environmental transformation resulted in the determination of significant changes in blood of animals exposed to the influence of urbanization and pollution. The qualitative differences in the adaptive strategy between three species of the genus Rana are shown from the example of hemopoiesis. The differences in population polymorphism of close species are found to affect them under anthropogenic transformation of the environment. Adaptiogenesis (one of the most important properties of animate matter) proceeds differently not only in different taxonomic groups of organisms, but also in related species and populations. Therefore, the comparison of hematologic characteristics in three species of the genus Rana (R. temporaria, R. arvalis, and R. ridibunda) enables to find the species specificity of adaptation on the level of some organism’s system.
Evseev G.A., Semenikhina O. Ya., Kolotukhina N.K.
Larval and juvenile morphogenesis of shell structures in Septifer keenae Nomura 1936 was studied using a light microscope. A shell of S. keenae larva is D-shaped (PD-1). The second umbo stage is absent in ontogeny of S. keenae, but is known in other Septiferidae. In the course of juvenile development, three types of teeth appear on the hinge plateau, two types of them develop on the posterdorsal shell margin, and one type of teeth, on the anterior shell margin. Adults inherit three types of teeth originating from different morphogenetic fields. In addition, shells in adults bear nodular ribs and septum. Based on the morphostructures of larval and juvenile shells in S. keenae analyzed and its homologues in juveniles and adults of Septiferidae, Modiolinae, Crenellinae, Musculinae, Brachidontinae, and Mytilinae, it is shown that recapitulative characteristics are important with respect to phylogeny. The morphostructures, which may be used in phylogenetic reconstruction are: primary lateral teeth, secondary lateral dysodont and non-dysodont teeth, precardinal, cardinal, pseudocrenulative teeth, and septum. According to these characteristics, mytilids except for Mytilinae, form a sequence beginning with Modiolinae-Lithophagidae and ending with Septiferidae. Some recent Branchidontinae may be the nearest ancestral or sister taxa of Septiferidae.
A classification of the family Piophilidae proposed by J. McAlpine (1977) is discussed. The subfamily Neottiophilinae is suggested to consider as a separate family. The tribe Mycetaulini is included into the tribe Piophilini. Arctopiophila Duda, Boreopiophila Frey, and Parapiophila J. McAlpine are new junior synonyms of Allopiophila Hendel; Liopiophila Duda is a new junior synonym of Prochyliza walker. Parapiophila caucasica Ozerov is a new junior synonym of Allopiophilla luteata (Haliday); Piophila coerulescens Zetterstadt is a new junior synonym of Stearibia nigriceps (Meigen). The lectotypes of Piophila coerulescens Zetterstadt and Piophila flavipes Zetterstadt are designated. One new species, Allopiophila pappi sp. n. is described from a male from Hungary. A list of genera and species of Piophilidae is given according to the classification proposed.
Timofeev S.F., Savinov M.V., Sklyar V.V.
The size of living and dead eggs in the euphausiid Thysanoessa raschii from different parts of the Barents Sea was studied. The mortality of eggs was shown to depend on their size. Dead embryos predominated among eggs with minimal and maximal sizes of embryos, i.e. having <300-μm and >350-μm diameters and the perivitelline space <25 and >50 μm, respectively. The size-dependent mortality of the euphausiid eggs is suggested to result from the stabilizing selection that provides a flexible equilibrium between egg size and fertility of euphausiids within the Barents Sea T. raschii population.
Granovich A.I., Mikhailova N.A., Znamenskaya O., Petrova Yu. A.
The species composition, ecological distribution, and trematode invasion of mollusks of the genus Littorina were studied in four localities of the eastern Murman coast. Six littorinid species were found: Littorina saxatilis (Olivi 1972), L. compressa Jeffreys 1865, L. arcana Hannaford Ellis 1978, L. littorea (Linnaeus 1758), L. obtusata (Linnaeus 1758), and L. fabalis (W. Turton 1825). The first three species belong to the “saxatilis” group, the rest ones, to the “obtusata” group. The conchological characteristics given in the article can be used to refer a mollusk to one of the species complex - “obtusata” or “saxatilis”. Species identification within each complex is possible when using such anatomical features as morphology of penis (for males) or pallial oviduct (for females). The more detailed characters are the length of penial filament, number and size of penial glands, size of copulative bursa, and the correlation between the length of the bursa and that of jelly gland. The analysis of the vertical zonation of littorinid species showed that L. compressa, L. obtusata, and L. fabalis inhabited the fucoid zone (populations of the latter species occupy the lower intertidal zone). L. arcana occurred on stones in the upper intertidal zone. L. saxatilis populations were found in a wide range of intertidal areas. The parasitological analysis of littorinids has revealed 12 trematode species. The data obtained cannot be used for the determination of differences between “saxatilis” and “obtusata” species complexes (or between the distinct littorinid species). The results are compared with the previously obtained materials about littorinids inhabiting the White Sea.
Varshavskii A.A., Naumova E.I., Tikhonov I.A.
An attempt to reveal a range of endoglucanase activity (EA) in forestomach and cecum of the common voles Microtus arvalis and M. rossiaemeridionalis was made. The relationships between the EA level and body mass, linear size, sex, physiological state, catching time, and the degree of filling rodents’ forestomach and cecum with food were determined. EA was measured by viscosimetric method. The data obtained were analyzed using the “Statistica” software package for estimating the influence of some factors on EA. Spearman and gamma nonparametric correlations and Kruskal-Wallis ANOVA were applied. The EA values in the gastrointestinal microflora of both species ranged from 3.0 to 130.2 μmol per gram of chymus in forestomach and from 16.8 to 237.0 μmol, in cecum. The mean EA values in forestomach and cecum were 24.4 and 79.5 μmol per gram of chymus, respectively. The relationship between EA and food composition was revealed from the example of East European vole. The reliable relations between EA in cecum and lactation were found, and correlation between EA in forestomach and that in cecum was determined. The tolerance of symbiotic microorganisms in gastrointestinal tract of common voles is suggested to be highly tolerant to the physiological state of hosts.
Tikhonova G.N., Tikhonov I.A., Surov A.V., Bogomolov P.L.
Studies of rodent and insectivore populations in grassy biotopes of Moscow were carried out in 1987-2001. Thirty lawns, 39 boulevards, 27 weeds, 40 meadows, and 18 small areas grown with meadow grasses were investigated. The analysis of small mammals' distribution, their number, proportion between different ecological groups, and species diversity showed that the less accessible biotopes for animals were lawns and boulevards. These habitats are very similar (according to Euclidean distances). The most suitable biotopes for rodents and insectivores are weeds and floodplain meadows. The urban A-E gradient of all biotopes indicates that meadows and weeds are more adequate to the “uninhabited anthropogenic community” concept. Such a community in these habitats is characterized by the lowest number of animals, low species diversity and the predominance of synanthropic and hemisynanthropic species of rodent and insectivorous animals. In all grassy biotopes, the abundance and diversity of small mammals increased from the center to peripheral areas of the city.
Lada G.A., Borkin L. Ya., Litvinchuk S.N., Ruchin A.B.