egg capsules of bithynia tentaculata gastropods shortly before hatching.
bithynia tentaculata dioecious (it has 2 separate sexes) , lays eggs on rocks, wood , shells in organized aggregates arranged in double rows, in clumps of 1–77. egg-laying occurs may july when water temperature 20 °c or higher, , second time in october , november females born in year. density of eggs on substrate can reach 155 clumps/m. fecundity may reach 347 eggs , greatest 2nd year class. eggs hatch in 3 weeks 3 months, depending on water temperature. oocytes develop poorly @ temperatures of 30 - 34 °c. growth not occur september may. lifespan varies regionally , can anywhere 17–39 months.
the faucet snail has potential biomonitor contaminants such cd, zn, , methylmercury (mehg) because there correlations between environmental concentrations , snail tissue concentrations respect these toxic compounds.
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