Pheres Blue (Aricia icarioides ssp. pheres)
Boisduval’s Blue (Aricia icarioides (Boisduval)) was described in the year 1852, the species is currently split into about 17 subspecies which are distributed nearly over all of North America, several of them being highly endangered.
The photo below shows one of the endangered subspecies, the Mission Blue (Aricia icarioides ssp. missionensis (Hovanitz)), a form that is highly restricted to a few localities in the San Francisco Bay Area.
The caterpillars of all subspecies feed on various lupine species (Lupinus spp.).
***
The Pheres Blue was restricted to sand dunes which once dominated much of what is now the city of San Francisco in Marin County, California.
The habitat of this local endemic was destroyed due to urban development, and the last Pheres Blues were finally seen in the year 1974 (?). [2]
***
A population of Boisduval’s Blue, morphologically close to the Pheres Blue, yet most probably not identically with it, was found in 1974 on the dunes at Point Reyes in Marin County, California. (see: Robert L. Langston: Extended flight periods of coastal and dune butterflies in California. Journal of Research on the Lepidoptera 13: 83-98. 1974). [1]
*********************
References:
[1] Robert L. Langston: Extended flight periods of coastal and dune butterflies in California. Journal of Research on the Lepidoptera 13: 83-98. 1974
[2] Edward F. Connor; John Hefernik; Jacqueline Levy; Vicki Lee Moore; Jancy K. Rickman: Insect conservation in an urban biodiversity hotspot: The San Francisco Bay Area. Journal of Insect Conservation 6: 247-259. 2002
*********************
Photo: Patrick Kobernus; National Digital Library of the United States Fish and Wildlife Service
(public domain)
*********************
edited: 06.03.2017