I think they can digest mealworms, its more of a matter of Meal worms being bad feeders, as they are not very nutritious.
Folklore, adds to it like this post myth that supers/meal worms eat their way out of the animal.
Mealworms are a common feeder for beardies ect. They don't have much issue, a well hydrated healthy animal shouldn't.
There is still the argument for Chameleons, that they would not eat either in the wild. If that matters to you. Its something I would like to push for personally. For beardies and ground lizards Mealworms, roaches, worms, crickets would be on the menu. For chameleons they really are not.
Beetles are, and Mealworm beetles fed fruit and pollens, may be viable for that reason. Flies are by a large margin, bees / wasps, hard for many folks to obtain. Katydids, and Leaf insects and of course Sticks are also likely on the menu.
Now if we look at the breakdown, I am on my phone atm, but we have a few long threads on this topic. The feeders, the majority is Bees(wasps) / Flies / Beetles. That should be where we as hobbyist keepers should be focusing IMO. Add in whatever sticks or what not we can, for more variety surely.
In doing that, a large portion of the diet is softbodied (see flies) and some is fibrous (see beetles) which should take care of the impaction issues.
Chameleons in nature, are never going to eat most of the "Loved" feeders. See Hornworms, Silkworms, Wax Worms, Superworms, Crickets, ect. The majority of what we feed is unnatural, and could be exaggerating the issues of impaction.
Not to knock Natalie's work, but this gives us a perfect example. Her common feeders in the hobby guide that Beman posted, is prime example. I have highlighted in Green, the Prey Items that Wild Chameleons ACTUALLY eat. As you can see, there is a stark difference from what we feed them, to what they actually eat.
Ladybugs, are said to be toxic, to all herps always heard that myself as well. Fun fact, of the prey studies, beetles make up 30% of the diet, and a very large portion of the beetles, is ladybugs.
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