Seasonal dynamics of morphometic traits of older stages specimen in a natural population of Baikalian epischura

Seasonal dynamics of three morphometic traits of females and males of VI, V and IV copepodite stages of Epischura baicalensis in Southern Baikal natural population was study. On cephalothorax length seasonal dynamics was specific: females and males of VI and IV the values of trait were lower at spring and summer then in autumn and winter; otherwise, specimen of V stage these values higher at spring and summer then in autumn and winter. On length caudal chaetae and the fifth hair of swimming legs of mostly age-sexual categories the values were higher at spring and summer then in autumn and winter. The receiving data let to propose the significance influence on seasonal dynamics of E. baicalensis body size.