Glaucopsyche piasus umbrosa
Smoky Arrowhead Blue
Another subspecies named in the 1998 Systematics publication (pp.172-3). The types were collected by John Emmel in the mid-1980s on a slope two-tenths of a mile east of Big Laguna Lake in the Laguna Mountains. He found them associated with Lupinus formosus. What sets these apart from other arrowhead blues is the darker ventral ground color, with the white "arrowheads" less developed. They fly in a single brood in the spring, with most records from April to about mid-May. As with the others in this species, the eggs are placed in the lupine flower buds, larvae emerge and feed to pupation, and overwinter as chrysalises. Eggs are easily found as shown below.