Anise Swallowtails are widespread and numerous in the west and are so-named for the caterpillars’ penchant for feeding on plants in the parsley family, including the introduced sweet fennel, or anise. These are some of the first swallowtails we see in the spring, flying from late April to July among bare hills, mountains, gardens, fields, vacant lots, and roadsides. They are very easy to mistake for the Old World Swallowtail (Papilio machaon). To tell the two species apart, you need to focus on the “eyespot” on the hindwing. On the Anise, the black spot is centered or circled with orange. The black eyespot on the Old World touches the inner edge of the hindwing. Definitely tough to see unless you get a photo.
Size: Caterpillars grow to around 5 cm in length
Photo by: Barb Lancaster on 7/15/22 in Columbia Falls, MT