Specific biological features and genetic variation of Chinese sleeper Perccottus glenii (Odontobutidae) in aquatic bodies of Tyumen oblast

Specific biological features, morphology, and genetic variation of an invasive species, the Chinese sleeper Perccottus glenii , in several lake and river ecosystems of the Tyumen oblast have been studied. This species displays relatively high rate of linear and weight growths. The main feed of the Chinese sleeper in both the river and lake ecosystems is the chironomid larvae. The diet is richer in the river ecosystem; predation plays an important role; and cannibalism is observed. As has been shown, the qualitative and quantitative characteristics of the Chinese sleeper infestations with local helminth species are by one order of magnitude lower as compared with the native fish species. A significant infestation rate is observed only for Nippotaenia mogurndae , a parasite specific for the Chinese sleeper. The population of this introduced species displays a high genetic variation for DNA markers. The rate of polymorphic ISSR bands is 73% and Nei’s genetic diversity is 0.26. The Chinese sleeper populations in the not directly connected river and lake (distance, 90 km) display a genetic identity of 99.5%, suggesting the absence of genetic differentiation of local populations, explainable by their recent origin from a single source of invasion. Morphological differences of the Chinese sleeper in different ecosystems appear on the same genetic basis and suggest a wide reaction norm characteristic of this species, underlying its ecological plasticity.