The Research Of Living Species Life Cycle And Environmental Significance On The Ostracod Limnocythere Inopinata In Tibetan Plateau

Limnocythere inopinata(Baird)is a Holarctic species,dominating many lacustrine extant ostracod population and numerous fossil strata in the Tibetan Plateau,with important taxonomy and(paleo)ecological application prospects.However,the complete life cycle,and precise temperature/salinity tolerance range and suitable range of the living L.inopinata in the Tibetan Plateau is still unclear.This study provides reliable evidences on the life cycle and environmental significance of L.inopinata by the indoor bioculture,observation experiments and temperature/salinity experiments for L.inopinata living bodies collected from Jiang co,Naqu district,northern Tibet.Results show that L.inopinata living in the Naqu area has a special growth process differently from Brooks' s rule,and more importantly,it is the first record that this species from the larval A-5 to the A-4 stage is a very significant growth stage.Many differences occur in the morphological characteristics of the soft appendages between L.inopinata adult and European L.inopinata female,with most obvious difference in the first thoracopod.Meanwhile,L.inopinata temperature tolerance range is narrow,about 11-17?,and temperature suitable range is about 11-14?,the salinity tolerance range is small,i.e.about 0.5-9.5‰,and the salinity suitable range is about 0.5-6.5‰,differing from the literature records about L.inopinata ecological tolerance range.All these evidences suggest that L.inopinata living in the Naqu area,Tibetan Plateau is likely to be a subspecies,i.e.after a long period of growth and reproduction,it has evolved into a group different from other L.inopinata population with a special growth process and soft appendages,adapting to mesothermal,oligohaline water environment.