phenetics of the gudgeon gobio gobio from waters of the southern kazakhstan (central asia)

Gudgeon is a native fish species for basins of the Southern Kazakhstan. This fish is an important species for extermination of water larvae of gnats here. Earlier it was considered as a subspecies named the Turkestan gudgeon Gobio gobio lepidolaemus Kessler, 1872. Data were collected since 2009 in the basins of the Syr Darya, Talas and Chu Rivers. Modern distribution of the gudgeon and some phenes like length of barbells, number of spots on body, fins coloration and disposition of scales on throat were investigated. No one Turkestan gudgeon was found in the Syr Darya River, but this fish remains one of the most common species in tributaries. Turkestan gudgeon inhabits in the large rivers like the Talas and Chu. The maximum length of the fish here was 188 mm, that is close to data collected before intensive anthropogenic impact on the region. Significant intra- and interpopulation variability in frequency of investigated phenes was revealed. Three forms of scales disposition on throat were revealed: completely covered with scales, half part with scales and naked. All 3 forms had been observed in the basin of Chu River and 2 forms in the basin of the Talas River. Some individuals without coloration of ventral and anal fins as well as increasing of variability of number of spots were discovered too. Fishes with short barbels were found in the Koltogan and Talas Rivers. Appearance of different forms in the populations of gudgeon in freshwaters of the South Kazakhstan can be result of environment changes and hybridization with alien Abbottina rivularis.