Featured Insect

Taxonomy: Class Hymenoptera, Family Braconidae,

Genus Aphidius, Species Colemani

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Biology: Aphidius colemani or the parasitoid wasp, is an organism that feeds off a living host during part of its development, which inevitably leads to the host’s death. This is unique from other parasites, which usually leave the host alive. This species female uses her antennae to seek out aphids, then lands on the back of one. Using her ovipositor, she lays her egg and flies off. The egg hatches and the larva feeds off the host until it break out, killing the aphid. The larva then wraps a silk around the aphid, mummifying it as the larva turns into a pupa. The adult wasp eventually emerges to mate (if needed), and the cycle starts again. These insects have become essential in biological pest control for farmers and gardeners because of their singular goal of killing crop-destroying aphids.

 

Range: The only way for a parasitoid wasp to pass on its genetics is to mate and lay its eggs in the aphids. So really, it’s difficult to determine their flight range since they’ll go as far as they need to for reproduction. As far as host range, Aphidius colemani attacks only select species of aphids to parasitize.

 

Habitat: Aphidius colemani prefer temperatures of 64⁰ – 75⁰ F so temperate zones are best. They can survive indoors as well as outdoors, as they are not affected by day length. They are mostly used in vegetable crop production. They are most effective against aphids in the spring and early summer.

 

Diet: Aphidoidea- aphids and their honeydew.

 

Life Cycle: Egg – larva – pupa – adult. Complete life cycle takes 14 days, 10 of which are spent in development from egg to adult. (Some adults can live another 7 days after that.) The female can lay between 100 - 300 eggs in her short adult stage.

 

Interesting behaviors: Females emerge from fertilized eggs while males emerge from non-fertilized eggs. The female: male ratio is 2:1.

 

Relevant Information to Critical Issue: Aphids cost farmers hundreds of millions of dollars annually in crop loss. Many species have adapted to sprays and new methods are needed. Biological control with a natural predator like the parasitoid wasp is a great way to combat the problem.