The scarlet tiger moth is a colorful moth belonging to the tiger moth subfamily, Arctiinae. The species was first described by Carl Linnaeus in his 1758 10th edition of Systema Naturae.

The Arctiinae are a large and diverse subfamily of moths with around 11,000 species found all over the world, including 6,000 neotropical species. This subfamily includes the groups commonly known as tiger moths, which usually have bright colours, footmen, which are usually much drabber, lichen moths, and wasp moths. Many species have "hairy" caterpillars that are popularly known as woolly bears or woolly worms. The scientific name Arctiinae refers to this hairiness. Some species within the Arctiinae have the word "tussock"' in their common names because they have been misidentified as members of the Lymantriinae subfamily based on the characteristics of the larvae.