Mission blue butterfly

In the male Mission blue, the dorsal surface of the wings gradate from ice blue in the center to deep sky blue towards the outside of the wings. Photography tends to misregister the blue on the wings as purplish due to light scattering. The margins of the upper wing are black and sport "long, white, hair-like scales". The male butterfly also has small circular gray spots in the submargins on the ventral surface of the whitish ventral wing surface. In the post-median and submedian areas of the ventral surface black spots mark the upper and lower wing. The male's body is a dark-blue/brown color. In females the upper wings are dark brown, but otherwise mirror males. The larvae feed exclusively on the leaves of their hostplants, Lupinus albifrons, Lupinus formosus, and Lupinus variicolor. ==Range==

I. i. missionensis is federally endangered and found in only a few locations. The butterfly depends solely on three species of perennial lupine for its reproduction, the varied lupine, silver lupine, and the summer lupine. The Mission blue requires the lupine to lay their eggs and nourish the larvae. Without these species, it cannot reproduce and thus cannot survive. Much of the area that the Mission blue once inhabited has been destroyed. The coastal sage and chaparral and the native grassland habitats have seen unnatural human development in much of the region. The San Mateo County town of Brisbane lies in what may once have been the prime habitat for the butterfly. Near Brisbane, an industrial park and rock quarry have proved damaging to the Mission blue habitat. Generally, the most negative impact is that of residential and industrial development. Aside from development, other human activities have negatively affected the butterfly's habitat. Those activities include cultivation and grazing as well as the oft human assisted abundance of invasive exotic species. Some of the more impactful exotics include the European gorse and pampas grass. The Mission blue was first collected in the Mission District of San Francisco in 1937. Today, a small colony occurs on Twin Peaks; the subspecies has also been found in Fort Baker, which is in Marin County. However, the majority of today's Mission blue colonies is found on San Bruno Mountain. Besides those on the mountain, other colonies have been found in San Mateo County. Those colonies have been located at elevations of . Some colonies have been found in the "fog belt" of the coastal mountain range. The Mission blue colonies in the area prefer coastal chaparral and coastal grasslands which are the predominant biomes where they are found. ==Status==

The Mission blue was added to the Federal Endangered Species List in 1976. ==Life cycle==

Only one generation occurs per year. The butterfly lays its eggs on the leaves, buds, and seed pods of L. albifrons, L. formosus, and L. variicolor. The eggs are usually laid on the upper side of new lupine leaves. Eggs generally hatch within 6 to 10 days and the first- and second-instar larvae feed on the mesophyll of the lupine plants. The caterpillars, extremely small, feed for a short time and then crawl to the plant base, where they enter a dormant state, known as diapause, until the late winter or the following spring. Diapause usually begins about three weeks after eclosion and begins about the same time as the host plant shifts its energy to flower and seed production. The adult Mission blue lives about a week; during this time, the females lay the eggs on the host plants. The complete Mission blue butterfly life cycle lasts one year. ==Host plants==

File:Lupinus variicolor (varied lupine).JPG|The varied lupine, Lupinus variicolor File:Lupinus albifrons.jpg|The silver lupine, Lupinus albifrons File:Lupinus formosus.jpg|The summer lupine, Lupinus formosus ==Predators==

In the 1983 study "Six Ecological Studies of Endangered Butterflies", R. A. Arnold found that about 35% of eggs collected in the field were being parasitized by an unknown encyrtid wasp. Other parasitic Hymenoptera have been taken from the eggs of various Icarioides species. As far as predator-prey relationships, rodents are probably the primary predator of both the larvae and pupae. ==Taxonomy==

The trinomial name of the Mission blue is Icaricia icarioides missionensis, since it is a subspecies of Boisduval's blue (Icaricia icarioides). However, since that species used to be classified in the genus Plebejus, some authors use the trinomial name Plebejus icarioides missionensis. ==Habitat conservation==

The U.S. Fish and Wildlife Service (USFWS) has a number of habitat conservation programs in effect which includes lands traditionally inhabited by the Mission blue butterfly. A recovery plan, drawn up by the USFWS in 1984, outlined the need to protect Mission blue habitat and to repair habitat damaged by urbanization, off-highway vehicle traffic, and invasion by exotic, non-native plants. An example of the type of work being done by governmental and citizen agencies can be found in the Marin Headlands at Golden Gate National Recreation Area. In addition, regular wildfires have opened new habitat conservation opportunities, as well as damaging existing ones. ==References==