Found from sea level to tree-line in a great variety of habitats; often common. An early-spring species, probably single-brooded but with hints of a second generation at the lowest elevations (which might be due to staggered emergence on different slopes). Males are territorial perchers. Both sexes visit flowers, including those of Redbud early in the season and Yerba Santa later. There is so much variation in habitat, host-plant association, and ventral color and pattern that this may actually be more than one biological species; it is by no means clear that it (or some components of "it") is actually conspecific with the eastern I. augustinus. Host plants include Dodder (Cuscuta)(!), Soap Plant or Amole (Chlorogalum, Liliaceae!), and flower buds or young fruit of Ceanothus and Arctostaphylos species - a bizarre mix indeed, though there is nothing to suggest any local population uses more than one of them. Late January or February to July, depending on locality.
Incisalia augustinus iroides
Western Brown Elfin