The Anise Swallowtail, Papilio zelicaon, is a North American species and is primarily found west of the Rocky Mountains. In the East, the Eastern Black Swallowtail, Papilio polyxenes, is predominant and feeds on the same host plants. The caterpillars feed on plants in the carrot family such as parsleys and parsnip, fennel and dill.
The adults are active and skittish, making them difficult to photograph. I stalked this nectaring butterfly for several minutes and only got a few good glimpses. The weather in Utah was cool and overcast, not very good weather for insect flight. Hopefully, the weather will improve and I can get some better photos.