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  • Author: L. Samchyshyna x
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Faunistical Overview of Calanoid Copepods (Crustacea) from Continental Waters of Ukraine

Faunistic overview together with updated checklist, comprising 38 species and 2 subspecies of calanoid copepods inhabiting fresh and brackish Ukrainian waters classified in three families and twelve genera is provided. The only freshwater calanoid species endemic to Ukraine is Speodiaptomus birsteini Borutzky, 1962, a stygobiont found once in an underground lake in the Skels'ka Cave (Crimean Peninsula). Two species, Hemidiaptomus (Hemidiaptomus) rylovi Charin, 1928 and S. birsteini are included as a threatened species in the Red Book of Ukraine. Dubious records and distribution patterns of some calanoid taxa are discussed. The calanoid fauna of Ukraine is compared with those of adjacent countries.

Ecological Characteristic of Calanoids (Copepoda, Calanoida) of the Inland Waters of Ukraine

The article presents analyze of known published data and own observations on ecology of freshwater and brackish calanoid copepods of fauna of Ukraine. The briefly characteristic of main types of waterbodies inhabited by calanoids is given. The relation of species to the important ecological factors of water environment like temperature, habitat permanence, salinity, pH, current, suspended matters, and interaction with other hydrobionts is analyzed.

Chorion Structure of Diapause and Subitaneous Eggs of Four Diaptomid Copepods (Calanoida, Diaptomidae): SEM Observations

Scanning electron microscopic examination of diapause eggs of freshwater Calanoida Hemidiaptomus amblyodon Marenzeller, Eudiaptomus vulgaris (Schmeil), E. graciloides (Lilljeborg) and subitaneous one s of E. gracilis (Sars) is described. The chorion surface ornamentation and number of coated layers are revealed. Diapause eggs have a thick (0.6-4.8 μ), at least two-layered chorion with patterned surface, whereas subitaneous eggs have a thin (0.13-0.25 μ), single-layered chorion with smooth surface. The mean number of eggs in egg sac, diameter of eggs and thickness of chorion were measured. The significance of the egg chorion thickness for diaptomid species inhabited temporary and/or permanent water-bodies is discussed.

Conception of Crossed Populations: Application in Cyclopoida Taxonomy

The conception of crossed populations in wide practice of taxonomic investigations in Cyclopoida is used for the first time. Applying this conception in taxonomy of cyclopoid copepods we based on revealed facts of the coexistence of sibling species which keep a little morphological hiatus. Hence, next pairs of species we consider as independent ones: Eucyclops speratus (Lilljeborg) and E. serrulatus (Lilljeborg); Paracyclops poppei (Rehberg) and P. fimbriatus (Fischer); Megacyclops latipes (Lowndes), M. viridis (Jurine) and M. gigas (Claus); Diacyclops clandestinus (Kiefer) and D. languidoides (Lilljeborg); D. hypnicola (Gurney) and D. languidoides (Lilljeborg); D. odessanus (Schmankevitsch) and D. bicuspidatus (Claus); Microcyclops rubellus (Lilljeborg) and M. varicans (Sars); Halicyclops septentrionalis (Kiefer) and H. neglectus (Kiefer). Facts of coexistence of Acanthocyclops americanus (Marsh) and its form A. americanus f. spinosa (Monchenko) differing by only one qualitative feature (spine or seta on outer edge on endopodite P4 distal segment) that has no transitive manifestation do not allow us to consider morphological form A. americanus f. spinosa as a separated species from the type A. americanus.