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273Гигантская личинка, пойманная в Чуйской долине и определенная А.И. Янушевичем (1976) как Pelobates fuscus, на самом деле, относится к Rana ridibunda. Таким образом, нет никаких оснований включать семейство Pelobatidae в список фауны Киргизии. Еще один гигантский головастик озерной лягушки был пойман в Иссык-Кульской области.
Обнаружены различия по составу фенофонда и встречаемости выделенных фенов у Rana ridibunda. Максимальное разнообразие по полиморфным признакам из группы фенов maculataventris наблюдается в островной популяции озерной лягушки. В популяции из Кольцовской воложки высокий уровень разнообразия отмечен у фенов в группе striata, maculatacollis и maculate. Анализ полиморфизма по признакам окраски показал, что между двумя выборками имеются значительные различия по большинству из исследованных фенетических признаков.
Anuran vocalizations are valuable in the determination of species identity and have the potential to discriminate intraspecific variation. We developed novel bioacoustic sampling techniques, based on Fast Fourier Transforms, to increase the precision and sensitivity of male advertisement call analysis and applied the method to European water frogs. This approach robustly separated the three types of north European water frogs (Rana ridibunda, R. lessonae and their viable, fertile hybrid R. esculenta) by their call subunit characteristics. The hybrid frog exhibited a high frequency call component absent from both the parental species. Furthermore, call analysis demonstrated significant intraspecific differences among populations of all three frog types. Call characters of R. ridibunda changed systematically as a function of longitude. This trend may reflect either clinal variation in selection pressures across Europe, or the consequences of drift following postglacial colonization from eastern refugia. High resolution vocalization analysis therefore provides a potentially useful method for investigating intraspecific differentiation and the phylogeographical origins of anuran distributions.
A study of the influence exerted by fluctuations in pH and illumination on larvae of lake frog (Rana ridibunda Pallas) has shown that their growth and development are considerably enhanced under certain variable size and weight, which suggests a positive effect of pH and illumination fluctuations. regimens, with the mortality and variability of tadpole size becoming lower and the duration of the larval stage shorter. First-year individuals raised with the factors studied variying, were larger and showed smaller variation in size and weight, which suggests a positive effect of pH and illumination fluctuations.
Patterns of advertisement call were investigated in two genetically distinct water frog lineages (Rana kl esculenta, Rana. kl grafi), which were identified by starch gel electrophoresis - the aim being to determinate the role of vocalization in the hybridogenetic process. Both hybrids displayed major modifications from the basic structure of the Rana ridibunda call. In Rana kl grafi, the call structure tended to correspond to that of Rana perezi in most of the studied parameters (frequency, duration, number of pulses) whereas the call of Rana kl esculenta tended to resemble that of Rana lessonae. The ascendant hierarchical classi®cation clearly revealed such a convergence toward parental species and accounted for a divergence between hybrids. Changes in call patterns might result from both the expression of the non-ridibunda genome and the sexual selective pressure through female mate choice. Only few non-ridibunda females exhibited a preference for hybrid calls which, however, allowed some hybridogenetic males to obtain successful mates. Thus, hybridogenesis induced character convergence in courtship signal with the non-ridibunda species in hybrid zones. In any case, these changes in the courtship signal favoured the particular hybridogenetic process, which constitutes a quasi-parasitism of the non-ridibunda genome.
Eight morphometric features of water frogs of 14 localities in Turkey, Syria, Jordan and Israel were compared with those of Rana ridibunda in Kazakhstan, Armenia and Greece (Thrace). These study sites include the type localities of R. ridibunda, R. r. caralitana, R. esculenta var. bedriagae and R. levantina. Multivariate comparisons (principal-component analysis, discriminant analysis) based on the log10-transformed variables demonstrate that the data set includes only two taxa that differ significantly in size and shape. By applying a morphospecies criterion, R. ridibunda is represented exclusively by the three reference populations, whereas all other populations (in Turkey, Syria, Jordan and Israel) represent the same species, R. bedriagae.
Temporal characteristics of advertisement calls of water frogs of 10 localities in Turkey, Syria, Israel and Egypt were compared with those of Rana ridibunda in Kazakhstan, Armenia and Greece (Thrace) as reference populations. These study sites include the type localities of R. ridibunda, R. r. caralitana, R. esculenta var. bedriagae und R. levantina. The temperature-dependent as well as the temperature-independent call parameters clearly revealed two species. R. ridibunda is represented by the three reference populations and, in addition, a population in central Turkey. The other populations (in Turkey, Syria, Israel and Egypt) represent R. bedriagae. R. bedriagae is the oldest available name for water frogs of these regions and was given priority over R. r. caralitana and R. levantina.
