Callosobruchus Maculatus: Highly Harmful To Humans

Callosobruchus maculatus are not considered directly harmful to humans; although, as an insect pest they damage millions of tons of human food crops in the form of legumes every year (Torres et al. 2016). Physically, they are small beetles, approximately 3.5 mm long. Because Callosobruchus maculatus larvae feed and develop exclusively on the seeds of legumes, the beetles are commonly referred to as "bean beetles." Adult Callosobruchus maculatus have a very short lifespan of 6 to 14 days (Fox et al. 2006). During this short lifespan, adults do not eat or drink; instead, they spend all their time mating and laying eggs. Following mating, adult female Callosobruchus maculatus oviposit individual fertilized oval-shaped eggs on legumes, such as mung beans (Vigna radiata) (Torres et al. 2016). The females use glue produced inside their abdomen to attach their approximately 0.7 mm long, oval-shaped eggs to the legumes. Depending upon the environment, adult females can lay over 100 eggs. …show more content…
When a larva hatches from the egg, it does not leave the bean to which its egg was glued. In fact, the larva does not even leave the egg and explore the surface of the bean; instead, without moving outside the protection of its egg, it burrows through the seed's outer layer and into its endosperm. The larva then spends its entire juvenile lifetime inside the bean on which its egg was deposited. Depending upon the temperature, humidity, and other factors, the larva, eats, molts and following pupation and the completion of metamorphosis, an adult Callosobruchus maculatus emerges in 2 to 4 weeks. At that time, the adult Callosobruchus maculatus finally leaves the bean to which its egg was affixed and begins its short adult lifespan of 6 to 14