Abstract Life history characteristics of three sibling species including sibling HE1, HE3 and LE9 in Brachionus calyciflorus species complex collected from Lake Liantang and Pond Hehuatang in Wuhu City and cultured at 13℃, 18℃, 23℃ and 28℃ with 2.0×106 cells/mL of Scenedesmus obliquus was compared by means of life table demographic approach. The results showed that the differences in life table parameters among the three sibling species differed with temperatures. At 13℃, sibling species LE9 had longer life expectancy at hatching, average lifespan and generation time than sibling species HE3, and the highest net reproductive rate and intrinsic rate of population growth among the three sibling species. The percentage of mictic females in all produced offspring was similar among the three sibling species. At 18℃, sibling species LE9 had longer life expectancy at hatching and average lifespan than sibling species HE3, and longer generation time than sibling species HE1 and HE3. Sibling species HE3 had higher intrinsic rate of population growth than sibling species LE9, and produced the most mictic daughters among the three sibling species. However, the net reproductive rates were similar among the three sibling species. At 23℃, sibling species HE1 had the longest life expectancy at hatching, average lifespan and generation time among the three sibling species. Sibling species HE1 produced less mictic daughters than sibling species HE3. Both net reproductive rate and intrinsic rate of population growth was similar among the three sibling species. At 28℃ and among the three sibling species, life expectancy at hatching, average lifespan, generation time and intrinsic rate of population growth were all similar, sibling species HE1 had the lowest net reproductive rate, sibling species HE3 produced the most mictic daughters. The responses in life table parameters to increasing temperatures were different among the three sibling species. Temperature, sibling species and their interactions all significantly influenced generation time, average lifespan, life expectancy at hatching and percentage of mictic females in the produced offspring. Both temperature and sibling species affected markedly the net reproductive rate and intrinsic rate of population growth, but their interactions did not appear to be significant.
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