Ontogenesis of the Cricket Gryllus argentinus Sauss.(Orthoptera, Gryllidae)

摘要

The development of Giyllus argentinus Sauss. was studied under stable laboratory conditions: the temperature of 26°C, the air humidity of 60%, and the photoperiod of 12h light : 12 h dark. The life cycle of Gryllus argentinus includes four stages: egg, pronymph, nymph, and adult. The duration of embryonic development is 18 days. The depth of egg bedding in the peat is 9.63 ± 0.12 mm (n =145), the clutch containing 2-4 eggs. A female can lay over 1100 viable eggs during the entire oviposition period. Nymphal development includes 9 instars and lasts 97 days. The duration of nymphal instars (days) is: I—5; II—6; III—6; IV—6; V—8; VI—10; VII—13; VIII—14; IX—29. The duration of the adult life is 51 days in males and 69 days, in females. In theimaginal ontogenesis of males and females, three periods can be distinguished: pre-reproductive, reproductive, and post-reproductive. Males start to emit the aggressive signal on the 6th (5-8th) day (the pre-reproductive period). They enter the reproductive period (start to emit the calling song) on the 9th (8-13th) day. Females enter the reproductive period (become capable of responding to the calling song and of copulation) on the 9th (8-10th) day. Oviposition starts on the day after the first copulation. The reproductive period lasts about 40 (15-59) days in males and 58 (21-70) days in females. The post-reproductive period starts in females at the moment of finishing the egg laying period and in males, with disappearance of reproductive behavior.The period ends in the animal's death.