This is a a family of Lepidoptera with new world distribution with only 11 species distributed in North America. The family consists of 23 Genera. Adult flannel moths are stout-bodied, and very hairy. Larvae are called puss caterpillars and, with their long hairs, resemble cotton balls. They have venomous spines that can cause a painful sting and inflammation lasting for several days, and in some cases, the sting may cause headache, nausea, and shock-like symptoms.