Life Cycle. Systematic position: Insecta, Holometabola, Coleoptera, Curculionidae.. Common names: Rice weevil, greater grain weevil and lesser grain weevil. The powder was passed through one mm mesh sieve. Besides, its length is a bit longer and it is capable of flying. After copulation, adult female bores a hole in the grain with the help of its powerful jaws and deposit a single egg in the grain cavity. A male-produced aggregation pheromone which attracts both sexes occurs in Sitophilus spp. S. zeamais causes qualitative and quantitative damage to stored products, with grain weight loss ranging between The appearance of the Sitophilus Zeamais (also part of the four weevils) resembles the rice weevil (Sitophilus Oryzae), except that, the spots marked on the wing surfaces are more distinct. These insects are known as internal feeders or primary pests. Life History: The life span of the adult weevil is 4-5 months. Life cycle: Optimal conditions are 120 days at 25-27 ºC. Distribution: Cosmopolitan, especially in the warmer parts of the world.. Morphology: The larvae of both species are apodous, whitish, with brown heads, about 3-4 mm long. The egg is oval in shape but they are elastic enough to fit in the hole made by the mother, who thereafter covers the egg with gelatinous fluid. Eleven grain protectants of diverse classes were tested for their ability in reducing the populations of Sitophilus zeamais. The habits and life cycle are similar to the rice weevil. Sitophilure, 5-hydroxy-4-methyl-3-heptanone, was reported to be the aggregation pheromone common for S. oryzae and S. zeamais, and Levinson et al. The larvae are mobile, and are external feeders. Tests were done to determine the exposure time required to kill all the life stages of maize weevils, Sitophilus zeamais, and the larvae of khapra beetles Trogoderma granarium. Adults are … The maize weevil, Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae), is one … Sitophilus zeamais which is an important species amongst the most destructive insect pests in the storage of Maize grains, the present experiment was conducted. The beetles convert approximately 400 sticky eggs on the breeding ground of the larvae. (1990) confirmed the activity of 4S,5R sitophinone and 2S,3R-sitophilate for Sitophilus spp. e maize weevil, Sitophilus zeamais Motschulsky (Coleop-tera: Curculionidae), is one of the most destructive stored product pests of grains, cereals, and other processed and unprocessed stored products in sub-Saharan Africa [ ]. The larval stage lasts 1 to 1.5 years and overwinter as larvae. They were carried out in airtight minisilos of 0.65 m 3 capacity, in the environment produced by maize of 13.5% moisture content stored under near to pure nitrogen. Sitophilus zeamais (Motschulsky) and Sitophilus oryzae (L.). The results