BIOLOGY OF CATHARTUS-QUADRICOLLIS GUERIN-MENEVILLE (COLEOPTERA, SILVANIDAE) ON SOME SELECTED FOOD MEDIA

The life cycle of Cathartus quadricollis (Guerin-Meneville) was studied under ambient laboratory condition on maize, sorghum, wheat, cowpea and melon. Egg hatchability was found to be 95.5% with an incubation period of 3-7 days. Five larval instars were recorded based on head-capsule width measurements. The growth ratio of the head-capsule width ranged from 1.05-1.20 with a grand mean of 1.12. This range falls within the acceptable range in Dyar's rule. The mean growth rate of C. quadricollis after 2 weeks of rearing on maize, sorghum, melon, wheat and cowpea, ranged from 22.4 to 1.6. While the mean developmental periods of C. quadricollis on the selected food media ranged from 18.80 days on cut maize to 30.70 days on cut cowpea.