Members of the family Arctiidae possess many intriguing life history traits, including the use of ultrasonic signals or pheromones for communication during courtship. Most arctiid genera exhibit one of these behaviors, but both of these signals can be found in the same genus, Syntomeida Harris, making it useful for studying the evolution of these traits. Historically, the monophyly of Syntomeida has been questionable. Sixty-six Syntomeida and twenty-four outgroup specimens were examined. We scored twenty-three morphological characters from the head, thorax, and genitalia from these preparations. We then used this information to perform parsimony analyses, examining the monophyly and composition of Syntomeida. Our results suggest that Syntomeida is not monophyletic, containing members of the sister group Phoenicoprocta and two other unrelated lineages. We revised the current taxonomy of Syntomeida to reflect this phylogenetic information. Additionally, our data suggest that the use of ultrasound during courtship differs from current evolutionary hypotheses.