ECOLOGICAL AND MORPHOLOGICAL CHARACTERISTICS OF NEMATODES OF THE GENUS RHABDOCHONA, PARASITES OF THE MARINKA

The article presents results of the study of morphology and ecology of 3 species of nematodes of the genus Rhabdochona, which parasitize on the marinka, a typical representative of the Nagorno-Asian fauna of fish. We collected material from the species of Rhabdohona parasitizing on the marinka in the basin of the upper reaches of the Syrdarya River, in the mountain rivers Isfayramsay, Sokh and Shakhimardansay located in the south of the Fergana Valley, as well as in the mountain rivers Chodaksay and Rezaksay located in the north of the Valley. Features of morphology of the species Rabdochona denudata, Rh. gnedini and subspecies Rh. hellichi turkestanica were described based on the study results. The characterized species differ from each other in a number of characters, including the size of the body and the spicule, and the tail and egg shape. Nevertheless, there is still a considerable amount of work to be done for molecular and genetic identification of various forms of the species Rh. hellichi. The marinka that shows high morpho-ecological variability under the conditions of the study area, is a polyphage, which contributes to the fish infecting with nematodes, especially during the period of active post-spawning feeding. The nematode Rh. hellichi turkestanica (Skryabin, 1917) was considered a subspecies and is observed in the original form of this helminth and is recorded in Uzbekistan for the first time.