This is obviously a difficult question to ask. Try talking to a local university, zoo or nature center for people who can ID insects.
Toads are known to do well on domesticated crickets, I say stick with those. You HAVE to assume that these insects have defensive mechanisms that allow them to survive, or else their species would have gone extinct a long time ago.
>>Ok, I got a perplexing question. Would an American Toad be able to eat these insects without poisoning it?
>>BoxElder Bugs
>>Ladybird Beetles
>>JuneBeetles
>>Mayflies
>>All of these insects are in abundance this time of year, and need to know if they are safe if caught from a chemical free area. I know that lightning Bugs are generally toxic, and I wouldn't feed them to anything. Thanks alot.
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*Humans aren't the only species on earth... we just act like it.
".the oldest task in human history: to live on a piece of land without
spoiling it."
Aldo Leopold (1938)