Template-Type: ReDIF-Article 1.0 Author-Name: Annu Kumari Author-Workplace-Name: Research Scholar, Jai Prakash University, Chapra, Bihar, India Title: Reproductive Biology of the Predatory Water Bug, Diplonychus annulatum (Fabricius) (Hemiptera: Belostomatidae) on Anopheles Mosquito as Prey Under Laboratory conditions Abstract: The biology of the predatory water bug, Diplonychus annulatum (Fabricius) (Hemiptera: Belostomatidae), was studied under laboratory conditions using Anopheles (Diptera: Culicidae) wrigglers as prey. D. annulatum exhibits paurometabolous type of development passing through egg, nymph, and adult stages. An adult female lay about 6-14 egg batches with an average of 55.95±2.36 eggs per batch. Incubation period ranges from 8-11 days with a mean of 9.28±0.06 days and 79.63 % hatchability. The nymph passed through five instars before reaching the adult stage. The mean durations of the different instars were: 4.62±0.16, 4.22±0.15, 5.24±0.24, 8.06±0.58, and 15.86±0.61 days, respectively. The developmental period was 28-54 days (x̅=38.14±0.85 days). Longevity of females ranged from 110-283 days (x̅=196.76±12.53 days) while that of males was from 115-282 days (x̅=212.38±14.04 days). D. rusticus was found to be a voracious predator of Anopheles in the laboratory. The mean consumption rates for the respective instars were 10.0±0.35, 17.22±0.31, 36.48±0.73, 98.18±2.89, and 171.88±4.23 individual wrigglers per day. Keywords: Aedes aegypti, Belostomatidae, Diplonychus annulatum, Hemiptera, life history, water bug Journal: Inventum Biologicum: An International Journal of Biological Research Pages: 22-27 Volume: 6 Issue: 1 Year: 2026 File-URL: https://journals.worldbiologica.com/ib/article/view/201 File-Format: text/html File-URL: https://journals.worldbiologica.com/ib/article/view/201/369 File-Format: Application/pdf Handle: RePEc:adg:ibijbr:v:6:y:2026:i:1:p:22-27