Chlosyne californica

California Patch

This is a spring flying desert butterfly for the most part, but with summer rains it can be common later in the year and even abundant. In September, 2022 - a year with good summer rainfall in the deserts - I saw at least a thousand of these in the Mojave Desert Preserve. This butterfly can have varying amounts of orange and dark brown on the dorsal side of the wings. California Patches resemble Bordered Patches somewhat but are easy to distinguish from them, and the amount of variation in the wings is much greater in Bordered Patches. In the places I tend to visit, this butterfly seems to be a "boom or bust" species, barely seen some years and ubiquitous others, no doubt depending on desert rains. The host is Bahiopsis parishii, Parish viguiera, which is an aster of the deserts. Females lay their eggs on the underside of leaves of the host plant, and the spiny caterpillars are gregarious.

California Patch - Chlosyne californica
At Cottonwood Spring in Joshua Tree National Park. March 30, 2009.
California Patch - Chlosyne californica
California Patches were fairly common at Horsethief Creek and along Cactus Spring Trail on September 20-21, 2013, and they were the most common butterfly taking nectar on yellow roadside composites at Scissors Crossing on Sept. 28th. This photograph is from Scissors Crossing.
California Patch - Chlosyne californica
Chlosyne californica, Cactus Spring Trail, September 20th, 2013.
California Patch - Chlosyne californica
Chlosyne californica, same hike as above.
Caterpillar of the California Patch - Chlosyne californica
Here's a caterpillar of Chlosyne californica on the larval food plant Bahiopsis parishii. These looked like third instars to me. This was at Joshua Tree National Park, October 2, 2022. Note the characteristic feeding damage on the leaves, which can help you find the larvae.
Chlosyne california desciption by W.G. Wright
W.G. Wright named this butterfly (as Synchloe Californica) in 1905, with a typically-vague locality: the Colorado Desert.
Chlosyne california designation of lectotype
J.W. Tilden designated a lectotype in this 1975 paper. His description of his task in working with Wright's text is interesting.

©Dennis Walker