The Arctiidae tend to be a colorful, charismatic lineage. Over 11,000 species have been described. Arctiids represent roughly 6% of lepidopteran species diversity worldwide (Watson and Goodger, 1986; Goodger and Watson, 1995) and are an important component of Neotropical communities (Conner 2008). Their bright colors most likely function in predator defense, warning of the moths’ unpalatability. Many species are protected by compounds they produce themselves (e.g. histamines) or by compounds they acquire from their larval host plants (e.g., cardiac glycosides, pyrrolizidine alkaloids). Some chemically protected arctiids participate in Müllerian mimicry rings and may resemble other poisonous Lepidoptera or wasps. Some species are nearly identical with their wasp models (Simmons and Weller, 2006) and even mimic wasp behaviors (Blest, 1964). Arctiid larvae typically have secondary setae arranged on verrucae on all segments except the head, hence their common name “wooly bears.” The caterpillar of *Pyrrharctia isabella* (J.E. Smith) is familiar to many North Americans. Not all caterpillars, though, have secondary setae.