Hi Melissa,
This could be a little tricky...for those who have been here a while they know that I raise giant silks and sphinx moths - not for feeders but as a hobby, education and presentations that I do with them (you know, circus tricks and stuff - just kidding
) and that I will not even feed my cham a hornworm for this reason - hey, her name, Luna, is from one of the giant silks!
So the reason I am picky is not so much if they are OK or not but rather ones that I can feed to her and still sleep at night. I fed her a Drexel's Datana (see link below) the other day and had to look away. It was larger than the ones I will usually give her and they have very "furry" heads. Are you sorry you asked me this question yet?? So now that you know my weird hobbies...anything you can collect at lights at night are probably OK.
HOWEVER, what you need to keep in mind is where they have been. If they do not feed as adults chances are they are OK, but only Lepidoptera geeks like me would have any inkling as to what those might be. If a feeding adult has dinner at a flower (most feeding adult moths sip nectar) that has been sprayed with pesticide the moth will possibly contain some amount of it even if only residual. Some caterpillars can feed on leaves that have been sprayed, pupate, make it to adulthood OK if their cycle is short and still have residual toxins. I will not go any further with the biology lesson, that's if you are even still reading this.
So the type of moth is not quite as important as the frequency. If you continually feed your cham wild caught insects of any type, and they all contain residual toxins from human applied chemicals, they could build up to an unsafe level.
OK. Done with that. But here is what you HAVE TO READ: you must steer clear of ANY insects that sport warning attire - this wardrobe consists of combinations of reds, orange and yellow such as the monarch & lightning bugs are two commonly known insects. These insects naturally contain chemicals that make your cham ill - or worse (there was a study done with monarchs and blue jays to see if all the jays would puke - they did! LOL!). Since moths do not usually wear these bright colors, knowing the caterpillar color and food plant is important. If you find a caterpillar or moth and you are not sure what it is there are a few sites you can check out. One is moths of NA and you can check by state:
http://www.npwrc.usgs.gov/resource/distr/lepid/moths/mothsusa.htm
A companion site is Caterpillars of Eastern Forests and even if you do not live in the NE there are many crossovers http://www.npwrc.usgs.gov/resource/2000/cateast/families.htm
or you can post to the Butterfly/Moth forum here. I frequent it and do lots of i.d.ing
You may have decided this isn't worth it all - and frankly that would make me happy b/c you may feed it some moth species that I spend an entire year raising from egg to adult - or you can collect an occasional moth at your light and feed it. I am sure many other keepers think I am nuts and feed their cham wc insects all the time with no problem, but hey, you asked me...so NOW are you sorry?? ;-/
lele and her Lepidoptera
drexel's datana
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0.1 veiled - Luna
0.2 house geckos - Gaia & Tia (MIA 
0.2 felines - Kyndra and Líta