There are many snakes that eat insects, but a plentiful(also inexpensive),pretty, and easy to keep one, would be a Rough Green Snake(Opheodrys aestivus). When I was a kid(waaay back)in the 60's - 70's I had several that ate crickets, roaches,grasshoppers,ect.......I see them in pet stores from time to time............................................Doug

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Better to be silent and thought a fool, than to open mouth and remove any doubt!