Dermestids / Cleaner Crews

[JeffreH]

These all look like darkling beetles to me, either Tenebrio molitor or Tenebrio obscurus. The easier way for you to make a quick reference to tell if you have dermestid beetles is by the tips of the antennae; your dermestids will have what appear to be little clubs while darkling beetles have very thin uniform antennae.

Personally, I've never heard of using mealworms as a cleanup crew. I'd imagine they'd simply use the same resources as the roaches like you suggest. Dermestids may nibble on old scraps and moisture sources, but mealworms will be feeding almost exclusively on the same stuff as the roaches. I could maybe see them being useful in bins that have a lot of food debris scattered throughout the entire bin, making things smellier and increasing the odds of flies and whatnot setting up residence, but I've never actually used them. I think Dermestids, isopods, and springtails are the best cleaner crews you'll ever find for most purposes.

The beetles are "okay" to feed to some herps - and beetles have an important role as a food source in nature for many species, but they are very heavily scleritized and can be a burden on the animal as a result of all of that armor. I would only feed them to a larger herp who could readily crush them up; they are certainly an impaction risk in smaller frog species who will fare better feeding on the larvae.