Qureshi, S.A., Oatman, E.R., Fleschner, C.A., 1969.
Biology of the spider mite, Tetranychus evansi. Annals of the Entomological Society of America, 62: 898-903.
Abstract
The biology of T. evansi Baker & Pritchard (Acarina: Tetranychidae) was studied in the laboratory at 23.3 ± 1°C and 40–50% relative humidity, using Solarium douglasii Dunal as the host plant. The different life stages are briefly described, illustrated, and their measurements are given. The incubation period averaged 65.2, larval period 42.8, protonymph 42.7, and deutonymph 64.2 hours. The total time from egg to adult averaged 8.9 days. Time spent in copulation averaged 1¼ min. The preoviposition period averaged 21 hr and 37 min. Oviposition began the day after copulation and reached a peak on the 4th day with an average of 18.1 eggs per female. Fertilized females averaged 163.7 eggs in 26.7 days. Virgin females averaged 105.1 eggs in 33.1 days; only males emerged. Fertilized females lived an average 26.2 days, unfertilized females 34.5 days, and males 24.7 days. Females laid 86.8% of their eggs on the lower leaf surface. Leaf pubescence and relative humidity affected oviposition; fewer eggs were deposited on lightly pubescent leaves, and eggs were more evenly distributed on both leaf surfaces when the relative humidity was increased to 100%.
