Abstract
The female reproductive system of Diplonychus rusticus (Fabricius, 1781), Family Belostomatidae, consists of paired ovaries, paired oviducts, a common oviduct, a median genital chamber, and a median spermatheca. The male reproductive system consists of a pair of unequally lobed testes, each with seven testicular lobes, paired vasa deferentia, rod-shaped seminal vesicles, and a median bulbus ejaculatorius. Hatching duration shows a mean ±SD value of 8.4 ± 1.55 days and life cycle takes 52.1 ± 4.96 days. This species exhibits unilateral paternal care, which provides the female with time for foraging. The males shed the egg cluster after the nymphs emerge. There is less competition for food, as group feeding seems to be the strategy for this species, and optimal food size changes with intense hunger. Diplonychus rusticus feeds upon and thereby controls mosquito larvae, the nymphs doing so more effectively than the adults.References
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