Zerene eurydice, the California dogface butterfly, belongs to the family Pieridae and is a sister genus to Colias. The Zerene eurydice and the Colias both share the "characteristic of having yellow-orange and black wing coordination." Additionally the,"Colias and Zerene eurydice males have bright UV patterns on their wings." This species is endemic to California, and is California's state insect. The California dogface butterfly varies in its wing color and pattern.
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Description
The California dogface butterfly, gained its name as a result of the coloring of the wings of the butterfly, especially in the males. "The Zerene eurydice only has UV patterns on its dorsal forewings." The female mostly has yellow wings, with two black dots or dashes on each forewing, while the male has black on the outer edges of the forewing, usually enclosing a yellow-orange color and two black dots. Male Z. Eurydice butterflies have an iridescent pigment found in their dorsal forewings due to light reflecting chitin structures and this has been associated with mating success. The wing span of Zerene Eurydice measures on average 5.1 to 6.3 cm. The wings are covered with scales to assist "flight aerodynamics and heat insulation" and the overall body contains "setae hairs that sense vibration and touch." During the larva and pupal stages, the Zerene eurydice are greenish yellow(same colors as family Fabaceae), and depend on Amorpha californica and Amorpha fruitcosa for camouflaging from predators. Z. Eurydice butterflies usually begin their flights around 7 a.m. and fly until the afternoon. This is not continuous and the butterflies will often roost in bushes. The females usually depart in flight an hour or two after the males.
Threats
Threats towards the species Zerene eurydice include, "fire suppression which results in closure of habitat openings and may result in eventual overly intense fires that could eradicate populations." Zerene eurydice are also locally threatened by livestock grazing. For global status-most recently updated in 2019-classifies Zerene eurydice as G4, indicating "apparently secure."