Lesser Mealworm
Alphitobius diaperinus
The lesser mealworm, Alphitobius diaperinus, is a small darkling beetle whose larvae are also sold as buffalo worms, mini mealworms, or small feeder worms. It is smaller than the common yellow mealworm and has a narrow brown larva that pupates into a dark, oval adult beetle. The species thrives in warm, protein-rich environments, especially poultry litter, spilled feed, manure, and cracks around animal housing. In commercial poultry houses it is better known as a pest than as a feeder insect, because large populations can persist between flocks.
People manage lesser mealworms in two very different ways. Feeder insect producers culture them in clean grain-based substrates and gut-load larvae before feeding them to reptiles, amphibians, fish, or birds that need small prey. Poultry farms try to suppress them through litter management, sanitation, structural maintenance, and targeted controls, since beetles can damage insulation and may carry pathogens or parasites mechanically. They are hardy escape artists, so cultures need smooth-sided containers and secure lids. Unused larvae or beetles should not be dumped outdoors, where they may enter barns, stored feed, or waste areas.