Pontia sisymbrii sisymbrii
Spring White
The spring white is not as common as either Becker's white or the checkered white, and unlike those other Pontia species, it flies in a single spring brood. For its larval food plants it seems to favor Boechera species perennans (perennial rockcress) and pulchra (beautiful rockcress). Gordon Pratt says it uses Caulanthus hallii (Hall's caulanthus) around his home in Anza. Larvae feed on these mustards, pupate, and diapause in the chrysalis. They wait years for good conditions before emerging as adults.
A female spring white at Valyermo, L.A. Co., April 10, 2008.
Female Pontia sisymbrii at Sugarloaf Mountain, Big Bear. May 25, 2007.
Same spring white as above, Sugarloaf Mountain, Big Bear. May 25, 2007.
Another spring white at Valyermo, April 2, 2009.
Male spring white at Valyermo, April 2, 2009.
I found this larva of sisymbrii on Descurainia pinnata on April 27, 2017.
Boisduval's 1852 description of Pontia sisymbrii based on Lorquin's captures during the gold rush. The Parisian journal is Annales de la Société entomologique de France.
©Dennis Walker