[Cytogenetic Analysis of the Species Composition and Inversion Structure of Populations of Malarial Mosquitoes in the Astrakhan Region].

A cytogenetic analysis of Anopheles mosquitoes in the Astrakhan region was carried out. Three species of Anopheles were identified. An. messeae lives everywhere and prevails in all of the areas of research, An. hyrcanus is found in the southwest of the region, and An. maculipennis in the northern part of the region. The populations of An. messeae show a high level of inversion polymorphism for the sex chromosome and the third autosome. A clear clinal trend of an increase in chromosomal rearrangements XL1, 3R1, and 3L1 and a decrease in the frequency of evolutionary source alternatives was revealed in laraval hemipopulations of the species from south to north.

[Genetic aspects of sexual behavior in malaria mosquitoes on the basis of specific acoustic signals at mating].

Acoustic characteristics were studied in two species of the "Anopheles maculipennis" species complex, A. messeae and A. atroparvus. The species were found to clearly differ in sound frequencies, which was assumed to play a key role in species identification during mating in regions of their sympatric distribution. The sound spectrum in A. messeae was far more diverse than in A. atroparvus, which was associated with intraspecific inversion polymorphism of the former. Mosquitoes with the inversion combinations that were most common in populations of the central region of the A. messeae species area specifically differed in acoustic signal spectrum from each other. Hence, sound communication within the species was considered to be the main mechanism that is responsible for sexual partner selection and determines the chromosome associations observed earlier in individual karyotypes. Since males carrying different inversion combinations significantly differed in acoustic characteristics, females were assumed to play a main role in selecting the sexual partner.

[Inversion polymorphism and ecological specialization of malaria mosquitoes (Diptera, Culicidae) in Karelia].

The species composition and inversion polymorphism were studied in malaria mosquito larva hemipopulations of Karelia. Three malaria mosquito species--Anopheles messeae, A. beklemishevi, and A. maculipennis--were found in the region. The northern boundary of their range is at 65 degrees NL. The greatest species diversity was observed in biotopes of the central region. Within-species chromosome polymorphism was observed in larva populations of all three species. For A. messeae, maximum karyotype diversity indices were established for the southern and northern regions of Karelia.

[The population-and-species-specific structure of malaria (Diptera, Culicidae) mosquitoes in the Caspian Lowland and Kuma-Manych Hollow].

The authors studied the population-and-species-specific structure of malaria mosquitoes in the Caspian Lowland and Kuma-Manych Hollow (Republic of Kalmykia, Stavropol Territory). Five Anopheles mosquito species were identified. An. messeae and An. atroparvus were dominant; An. maculipennis, An. hyrcanus, and An. sacharovi were ecologically specialized and relatively rare. An. sacharovi was first found in Kalmykia, which is the most dangerous malaria vector in the south regions of the CIS. This allows the former known borders of its area to be expanded to the northwest Paleartics. An. messeae showed a high rate of inversions along both arms of chromosome 3 in homo- and heterozygous states, as well as a unique inversion in sex chromosome. The An. atroparvus population in the region was found to have a high rate of inversion on the 3L arm, which had been previously recognized as rare in Ukraine only.

[The population-and-species-specific structure of anopheles (diptera, culicidae) mosquitoes in the Upper Rhine Valley, Germany].

The authors studied the population-and-species-specific structure of malaria mosquitoes in the Upper Rhine valley, Germany. Four Anopheles mosquito species were identified. These included An. claviger, An. maculipennis, An. messeae, and An. plumbeus. The predominance coefficients of the species were determined. An. messeae is dominant; An. maculipennis is subdominant, An. plumbeus and An. claviger are rare. The latter two species are ecologically specialized and predominantly develop inthe biotopes that are inaccessible for dominant species. The karyotypes of An. messeae show a high variability in sex chromosome XL and a low rate of homo- and heterozygotes in 3R, inversion. The greatest species-specific and karyotypic variety of malaria mosquitoes is noted for large aquatic biotopes.

[Genetic determination of succinate dehydrogenase activity in Anopheles messeae (diptera, culicidae) larvae].

The present study aimed to reveal differences in the activity of a mitochondrial enzyme, succinate dehydrogenase (SDG), in larvae of mosquito Anopheles messeae with various karyotypes. Four-instar larvae of malaria mosquito previously obtained in laboratory conditions from imagoes collected in a taiga population of Tomsk region served as material for the study.

[Chromosome polymorphism and regularities of the subpopulation organization of malaria mosquitoes Anopheles (Diptera, Culicidae) in biotopes of the Tomsk oblast].

A biotopic subdivision was observed for the two closely related species Anopheles messeae and A. beklemishevi in larval biotopes of the Tomsk oblast. The regularities of the spatial distribution of A. messeae with various chromosomal inversions were determined. The A. messeae karyotypic structure proved to vary depending on the ecological conditions of wintering and reproduction sites. The frequencies of chromosome variants XL0, 2R0, 3R0, and 3L0 were maximal in villages, while forest biotopes were characterized by elevated frequencies of alternative inversions. A comparison of the chromosomal structure for larvae and adults confirmed the subdivision of spatial niches for adults with different karyotypes. The difference in spatial niches was assumed to reflect the ecological specialization of mosquitoes. At the interspecific level, such specialization allows closely related species to occur in sympatry regions. At the intraspecific level, a subdivision of spatial niches reduces the intraspecific competition, increases the population size, and improves the survival during unfavorable periods associated with changes in abiotic factors.

[Malaria mosquitoes in Moscow and in the Moscow Region: cytogenetic analysis].

The species and karyotypical composition of malaria mosquitoes in Moscow and in the Moscow Region have been examined. A cytogenetic analysis in the Moscow Region has revealed 3 types of malaria mosquitoes: Anopheles claviger Mg., An. maculipennis Mg., and An. messeae Fall. An. messeae predominates in the Solnechnogorsk and Noginsk Regions, An. maculipennis prevails in the Ramensk and Serpukhov Regions. In the combined habitats, the ratio of two predominant types has been ascertained to vary during a season. The proportion of An. maculipennis increases by the end of summer and decreases during hibernation. The more northern type of An. messeae has been shown to be superior to An. maculipennis in fertility. Thus, the increased relative size of An. maculipennis during summer is due to the higher viability of the larvae of this type. In the Moscow water reservoirs, the larvae of both types develop concurrently; the proportion of An. messeae is 89.8%. The high level of chromosomal variability was found in the urban populations of An. messeae by the inversions of XL1, XL3, 2R1, 3R1. A role of chromosomal variability in the adaptation of mosquitoes to urban conditions is discussed.

[Kin selection and developmental rate of malarial mosquitoes with different karyotypes]. / Otbor rodichei i skorost' razvitiia maliariinykh komarov v raznymi komarov s raznymi kariotipami.

Changes in the adaptive value of genotypes through the course of relationships within and between malaria mosquito families at larval stages were studied in Anopheles messeae, the species with chromosome polymorphism. It was shown that interactions between sibs can affect their viability and developmental rate. Larvae with "northern" inversions (r-strategists) developed significantly slower when kept together with larvae carrying the "southern" chromosome variants (K-strategists). A decrease in relative fitness was observed in larvae with the northern inversion XL1, which were kept on an insufficient diet. The relationship between kin selection and the formation of adaptive strategies in A. messeae are discussed.

[Strategies for selection and stability to asphyxia in larvae of the malaria mosquito Anopheles messeae with various karyotypes]. / Strategii otbora i ustoichivost' k asfiksii u lichinok maliariinogo komar Anopheles messeae s raznymi kariotipami.

Sensitivity to asphyxia (oxygen deficiency) Anopheles messeae larvae was studied. It was demonstrated that mosquitoes with mosquitoes with "northern" chromosome inversions perish underwater more more quickly than mosquitoes with "southern" karyotypes. Apparently, resistance to asphyxia is a component of the adaptive strategy and is maintained by K-selection. The respiration and energy metabolism of larvae with different gene complexes are discussed.