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Information × Registration Number 0217U003894, 0117U004741 , R & D reports Title Evaluation of Species Composition and Testing of Resource Potential of Crawfish in Prupyat River Basin popup.stage_title Head Harbar Alexander Vasyliovych, Registration Date 11-09-2017 Organization Zhytomyr State University named after Ivan Franko popup.description2 A comparative morphological analysis of the most massive samples of crayfish found in the Pripyat River basin - A. leptodactylus, A. angulosus and A. astacus was conducted. The results of discriminant analysis of the aggregate of dimensional characteristics and morphometric indices indicate a high level of discrimination (96.62%) of two types of long-lived crayfish (A. leptodactylus and A. angulosus). Cariological analysis showed that the studied groups, which by morphological features were identified as A. astacus, A. leptodactylus and A. angulosus, clearly differ in their chromosomes. Thus, it is established that in the diploid set A. astacus, the modal amount of chromosomes is approximately 2n = 90. This corresponds to the results of the cariological analysis of broad-healed cancers from the reservoirs of the foothills of Transcarpathia. The A. angulosus chromosome haploid set is n = 93 whereas A. leptodactylus is characterized by a haploid chromosome set of n = 88. The results obtained are similar to those of the Hungarian researchers, which indicate for A. leptodactylus sensu lato the number of chromosomes in the diploid set 2n = 180. A. astacus is an endangered species, with a decreasing range, its populations are stable only in the foothills of Transcarpathia. On the Carpathian and Podolian highlands there are some places, and there is a tendency towards its disappearance. Euribiontic and relatively adapted to modern environmental conditions were angular and long-lying crayfish, with more and more widespread undoubtedly angular crayfish. Despite the same biotope preferences, these species obviously have an antagonistic relationship, as evidenced by the lack of common settlements. The current state of the population of river crayfish is given, it is quite adequate to maintain the status of "disappearing" for wide-mouth crayfish. Product Description popup.authors Костюк Віталій Степанович Межжерін Сергій Віталійович popup.nrat_date 2020-04-02 Close