The biology of Sticholotis marginalis Kapur (Col.:Coccinellidae).
Sticholotis marginalis Kapur has been observed preying on several species of Coccids in West Pakistan, including Quadraspidiotus perniciosus (Comst.). It was fairly common among both light and heavy infestations of Leucaspis coniferarum Hall & Williams on Pinus spp. in the hills, but was found only rarely in association with other Coccids. The egg, larva and pupa of the Coccinellid are described.During rearing in the laboratory at about 75 deg F and 54% R.H., the females paired 6-9 days after adult emergence and began to oviposit after a further 5-7 days. They laid 31-75 (average 61) eggs each during 25-47 days. When Aonidiella orientalis (Newst.) was provided as prey, the egg stage, four larval instars and pupal stage averaged 8.6, 5.7, 4.3, 5.8, 7.8 and 8.4 days, respectively; adult males lived for 31-55 days and females for 42-76 days. When L. coniferarum was provided as prey, the daily consumption by first- and second-instar larvae averaged 12.5 and 24 eggs, or 6.8 and 13 crawlers, respectively. Third-instar larvae consumed an average of 4 second-instar nymphs daily, and fourth-instar larvae consumed daily 7 adult females or 18 first-instar nymphs. The adults consumed daily 8 adult females or 23 first-instar nymphs. The feeding rate was slightly lower when A. orientalis or Lepidosaphes sp. was provided.In the Murree Hills, adults of S. marginalis overwintered in cracks in the bark of P. roxburghii and oviposition began in March. The larvae and adults preyed actively on eggs and nymphs of L. coniferarum in April-May, and larvae of a second generation were present in June-July. Populations of the predator were highest on the most heavily infested trees.