Red-spotted Purple

Limenitis arthemis astyanax

The Red-spotted Purple is a common butterfly in the southern half of Wisconsin. Throughout central Wisconsin, this subspecies and the White Admiral are both present, and sometimes they hybridize. The offspring can have characteristics anywhere between the two subspecies. This butterfly is often found taking nutrients from gravel roads, roadsides, or scat. One year I had not seen any of this species flying, but found more than five dead along a roadside, apparently road-kills. They also commonly hilltop, and I can reliably find them at my favorite local hill, along with a Black or Eastern Tiger Swallowtail.

Identifying characteristics

Above, the Red-spotted Purple is mainly a black butterfly with iridescent blue, that is most impressive in fresh specimens and good light, where the red spots that are obvious from below can sometimes be seen. This butterfly is a mimic of the Pipevine Swallowtail and as such looks like a miniature swallowtail, but with no tail. There are a few white spots near the apex of the forewing. Below, this butterfly is black with blue spots in the wing margins, but obvious submarginal red spots in both the forewing and hindwing and some red spots nearer the body.

Similar species

This species, the Eastern Tiger Swallowtail, black female, the Black Swallowtail, and the Spicebush Swallowtail all mimic the Pipevine Swallowtail and so look somewhat like it, but all the Swallowtails are much larger than the Red-spotted Purple and have very obvious tails.

Habitat

Forest edges and openings, and roadsides and trails through wooded areas.

Flight

Two broods. Late May through July and then late July into August.

Abundance

Not usually seen in great abundance. Seen on 13 of the 32 NABA counts in Wisconsin in 2004 and 2005 with six being the greatest number of individuals observed.

Locations