Mealy bugs are a type of aphid surrounded by a sweet, sticky, fuzzy exudate that protects them from most preditors. They are found stuck solidly to the plants and do not go about freely. And no, since they don't appear to move, dart frogs won't even try to eat them. If this is what you have, either remove the plants they are on, as suggested, or you could conscientiously and (endlessly) touch each of them with a cotton swab dipped in rubbing alcohol. They are persistent little buggers.
All in all, I think you are relatively safe as far as the frogs are concerned. If it's not mealies, the population will diminish. Look carefully and see if your frogs are eating them. If so, consider it just another food variety. I introduce leaves of aphids (not the mealies) occasionally. The frogs love them as a kind of sweet dessert plate. They've never gone on to infect my tropical plants in the vivariums. There are several reasons for this, one being that the various species of aphids are relatively plant specific-- i.e. some infect fruit trees, some beans and peas, or others specialize in the cabbage family. So they won't usually go for what you have planted in a tropical terrarium even if the frogs don't get to them first.
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Patty
Lost River, Idaho
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