RESUMO
The scale mealybug, Diaspis echinocacti (Bouché, 1833) (Hemiptera: Diaspididae), is one of the main pests of the cactus pear in Brazil. The objective was to study biological aspects of D. echinocacti at the constant temperatures of 25, 28, 30, 33 and 35 °C with relative humidity of 60 ± 10% and photoperiod of 12 hours in the laboratory on the cactus pear cultivar, "Orelha de Elefante Mexicana", Opuntia stricta [Haw.] Haw. The development period (22 to 35 days) and survival in the egg (92 to 100%) and nymph (21.8 to 100%) stages and of the egg-adult cycle (20 to 100%), longevity (34.1 to 59.6 days) and fecundity (33 to 112 eggs) of D. echinocacti females with the different temperature and absence of males at the highest temperatures (> 30°C), indicated that the range between 25 °C and 30°C is the most favorable for this scale mealybug. This information may help to improve integrated management programs for D. echinocacti, in areas subject to seasonal temperature changes in the Brazilian regions where cactus pear is cultivated.