Answer: Delphastus has recently become widely available, and is definitely a beneficial insect. The tiny predaceous beetles work best at high population levels of whitefly as the adults must feed on at least 10 whitefly eggs per day in order to continue their own egg production. Both the adult and larval stages feed on whiteflies. I suspect that the smaller insects you're seeing are the offspring of your original release of delphastus.
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