Nymphal Development of Acanthosoma denticauda and A. haemorrhoidale angulata (Heteroptera, Pentatomidae) under Natural and Laboratory Conditions

In the field, the developmental period from the 1st ecdysis to the adult emergence was about 45 days in Acanthosoma denticauda and the new adults emerged in mid-August, while in A. haemorrhoidale angulata, the period was about 35 days and the new adults appeared early in August. In the laboratory, the egg period and the 1st instar period of these two species were between 5 and 6 days. Mortality in their nymphal stages was extremely higher at 30±1℃ than at 25±1℃. The sensitivity to high temperature was stronger in A. haemorrhoidale angulata than in A. denticauda. In A. denticauda, the 3rd and 4th instar periods were longer at 30±1℃ than at 25±1℃, while in A. haemorrhoidale angulata, the 2nd instar was shorter and the 3rd instar was longer at 30±1℃ than at 25±1℃. Difference in humidity had no or little influence on the developmental periods and the mortalities of these two species.