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May 16, 2020 09:00 am

These beautiful spring days are made even better by the late May rains. The many green colors are vibrant and refreshed by the coolness and water. It seems there are at least seven or more different shades and hues. As I am taking in this verdant carpet, a vibrant yellow butterfly lazily flits by. This is the elegant Anise Swallowtail, Papilio zelican, which can be easily confused with two other swallowtails it is related to. The Western Swallowtail, Papilio rutulus and the Pale swallowtail, Papilio eurymodon, also occur in Little Lake Valley.

How do we tell these three species apart? The Western swallowtail and the Pale swallowtail are very similar with four vertical black stripes on the upper side of the wings. However, the Western has its stripes against a yellow background and the Pale (as its name suggests) has those stripes against an off-white pale cream-colored background.

The Anise swallowtail is also black and yellow, but the top of the front wing has rectangles of yellow surrounded by black areas on both sides. This butterfly appears to have black shoulders.

All three species have forked hind wings near their rear which resembles antennae. This tricks bird predators into thinking they are going for the head of the butterfly. In addition, the hind wings have brilliant red spots surrounded by iridescent blue that are misconstrued as “eye spots.” Therefore, swallowtails are often missing these beautiful “tails.” I have photos of all three species nectaring on wildflowers. The Anise Swallowtail is on the flower called Blue Dicks, a Western Swallowtail is on the plant called Ocean spray, and the Pale Swallowtail is on a wild lilac.

In the book, Common Butterflies of California, the author Bob Stewart talks about the different host plants these butterflies use. These are plant species that butterflies lay their eggs on and its larvae will eat upon hatching. The Western Swallowtail is a riparian species that uses Willows and Alders to lay its eggs. The Anise Swallowtail uses many carrot family species such as Queen Anne’s lace, Poison hemlock, fennel, Hog fennels, and Yampah. The Pale Swallowtail prefers Ocean spray, California Coffeeberry, and the Hollyleaf cherry. 

As I am walking around in Little Lake Valley, I often see these large resplendent swallowtails flying and exploring the vegetation. Although there is a lack of the Monarch butterflies, these showy butterflies seem to be everywhere.