Aphidius colemaniGreen Peach Aphids? Melon Aphids? This Wasp Has a Plan. If youve already IDd the culpritgreen peach, melon, black bean, or lettuce aphidsthen you dont need another spray cycle. You need a predator that can find what you miss, and multiply while doing it. Aphidius colemani is a specialist parasitoid wasp that targets small bodied aphids. Each female injects one egg per aphid. Days later, youll start seeing swollen, tan colored aphid mummiesevidence