Abstract
Life-history parameters of Tetranychus viennensis ZACHER were investigated at 25 .+-. 1.degree. C and 15L-9D. The total developmental time was 12.1 (.female.) and 11.9 (.male.) days. The intrinsic rate of natural increase (rm), net reproductive rate (RO) and mean generation time (T) were 0.172, 32.32 and 22.14, respectively. These parameters are compared with data on Tetranychus urticae KOCH.