hi, i don't know about conventional wisdom, but i do mix species, at my own judgement. i set my tanks as ecosystems, so i have climbers with borowers and so on. i would say that if one could not fit into the other's mouth, and they don't occupy the same strata of your enclosure, you might try it. but remember that it is always at your risk, simply because their space of escape is limited. good luck A.
I was wondering if I could keep my sandfish and armadillo lizard in the same tank? They are about the same size. :Justin