Kwik-Key to Common Families of Lepidoptera
Answer for your specimen:
If you have reached this part of the key, your specimen should be a small to medium-size moth with a stout body and a dense covering of hairs and scales. Front wings are triangular and held tent-like over the body. Each hind wing should have three anal veins (unbranched).
The two likely families are:
Front wings are usually dark brown with an irregular spot of contrasting color. Antennae of male are bipectinate. Larvae are fleshy and slug-like with stinging hairs. They move by gliding on sucker-like prolegs.
Front wings are usually white, yellow, or brown with few distinctive markings. Antennae of male are bipectinate. Larvae are densely hairy and have stinging spines hidden among the hairs.