SMITH'S BLUE BUTTERFLY

Along the shore of Monterey Bay, from Seaside north through Ft. Ord to Marina is a set of coastal dunes. These have been coveted by developers for years; many are degraded by sand mining, or covered with non-native ice-plant, or heavily used as rifle ranges when Ft. Ord was operational. But where the wild, native buckwheat (genus Eriogorum) flowers (below left), for a short time in mid-to-late summer the tiny Smith's Blue Butterfly  Euphilotes enoptes smithi emerges from its chrysalis and flies from buckwheat to buckwheat (below right). The flight usually lasts only 4-6 weeks, and each individual adult butterfly lives only for about a week, during which time it must find a mate and, if female, lay eggs for the next generation. This taxon is listed as Endangered under the Federal Endangered Species Act.

Males are a vivid blue color above; both sexes are similarly patterned in white with black-and-orange spots below. This photograph of a male (right) is about 4 times life-size. Even the photo above is about 150% of life size for these tiny butterflies. In life, the wingspan is only ~1 inch across.
Females are brown above with a thin white fringe and an orange bar across the hind wing. Males emerge first in summer, followed by females a week later. After mating, females lay eggs on buckwheat plants. These hatch into caterpillars later in the summer, which feed on the flowers as they grow. Some species of ants protect the caterpillars from predators and parasites, and receive a sugary liquid in return. The caterpillars then pupate, and that remain dormant for the winter, until the buckwheats flower again the next summer. Only then do the new adults emerge (Arnold 1983).
This butterfly was discovered in 1948 at the mouths of Buck and Dolan creeks, on the Big Sur coast, by two U.C. Berkeley undergraduates, Rudi Mattoni and Claude Smith. It appeared to be a butterfly they had never seen before, so Mattoni collected some for future study. A few years later, Claude Smith was swept to sea and perished while fishing at Half Moon Bay. He had not yet finished his dissertation of the day-flying moth genus Annaphila. When Rudi Mattoni formally described the butterfly to science (Mattoni 1955) as a subspecies of the widespread Dotted Blue Philotes enoptes he named this butterfly in tribute to his friend Claude Smith. In 1975, this butterfly was reclassified this butterfly as Shijimiaeoides enoptes smithi, and that was the name used during the Endangered Species Act (ESA) listing process in 1976. Soon after, Mattoni (1977) revised the tribe Scolitantidini and transferred S. e. smithi to the genus Euphilotes.
The butterfly has two different lifestyles in Monterey County, both tied closely to two species of buckwheat (E. latifolium and E. parviolium). One population lives in the coastal dunes on Monterey Bay these are the ones photographed here. The other population exists in patches of coastal chaparral near the Big Sur coast, but extending slightly inland and upslope to Palo Corona. This latter population is the one originally discovered by Mattoni & Smith [more on this below].
Smith's Blue Butterfly always had a restricted range, but development and invasive plants decimated coastal dunes and chaparral habitats until less than half of those habitats remained locally (Powell 1981). After several Monterey County plants, lizards, and insects were listed as Endangered under the federal ESA, the U.S. Army under pressure from the local chapter of the Native Plant Society created a dozen of so small reserves on Ft. Ord. One of these was Reserve #10 (left or above), created for Smith's Blue Butterfly. This was the first federal preserve for an insect. In the 1980s, the Youth Conservation Corps uprooted invasive ice-plant and other exotics in the preserve (although there is still plenty of non-natives present in these dunes). During the decommission of Ft. Ord in 1990s, the coastal dunes were assigned for transfer to California State Parks. This transfer should be accomplished sometime in the not-too-distant future (this is written in July 2006). Another Threatened species, Black Legless Lizard Anniella pulchra nigra, also lives in these dunes [both the lizard and the butterfly are shown on the reserve sign; ironically, almost no one sees these signs because the area is not yet open to the public).
IDENTIFICATION: The taxonomy of Smith's Blue Butterfly is unsettled. As noted above, it is currently considered a subspecies of Dotted Blue Euphilotes enoptes. The identification of the blue butterflies can be complex and difficult. David Styer, however, explained to us the key features separating Smith's Blue from its most similar species, Acmon Blue Icaricia acmon and Lupine Blue  I. lupini (both occur on Ft. Ord). In Acmon/Lupine Blue, the underwings are patterned in white or light gray and dotted with black and orange (below left). On Smith's Blue (below right) the pattern is similar but (a) the base of the underwings are washed with dusky and (b) the outer edge of the forewing has a black-and-white checkerboard pattern (all-white outer edge of forewing in Acmon/Lupine; these latter two species are separable on upperwing pattern). The Smith's Blue in this photo is shown on a buckwheat and thus not enlarged as much as the other shot; they are both approximately the same size.
Recently, Pratt & Emmel (1998) proposed splitting the Monterey County populations into two subspecies based on their host plant preference. The originally discovered population in coastal chaparral uses only Seacliff Buckwheat Eriogorum parvifolium; they proposed this population be restricted as E. e. smithi. In 2002, new populations of this taxon were discovered on recently acquired U.S. Forest Service land near the Monterey/San Luis Obispo county line. The authors proposed a new subspecies, E. e. arenacola called the Marina Blue which they said feeds solely on Seaside Buckwheat Eriogorum latifolium, found in coastal sand dunes. This proposal is not yet widely adopted. For one thing, both buckwheat species occur on the Ft. Ord dunes and the butterflies there use the both! Indeed, the buckwheat shown in these photos is E. parvifolium, according to David Styer. For the moment, the ESA continues to protect all Monterey populations, although, if split, it would be the "Marina Blue" that is seriously endangered. But given the blue's use of both plants on the Ft. Ord dunes, it seems best at this time to continue to call them all Smith's Blue Butterfly.

The final photo (right) shows a worn and tattered female, presumably near the end of her week-long life as a full adult. Whatever the eventual taxonomy, the major threat to our coast dune butterfly is loss of habitat. These areas have been under intense pressure from development, but the creation of Fort Ord Dune State Park is a hopeful development for the future.

Acknowledgments: I thank David Styer for showing Rita Carratello and me these delightful little butterflies; I also thank David and Rita for pointing out good photographic opportunities. I also thank Dave Dixon of California State Parks for access to this restricted locale. Some of the information herein is summarized from a more complete account by Black & Vaughn (2005). David Styer provided useful comments on an earlier version of this page, and Dan Singer pointed out various grammatical errors. 
 

Literature cited:
Arnold, R.A., 1983. Ecological studies of six endangered butterflies (Lepidoptera: Lycaenidae): Island biogeography, patch dynamics, and design of habitat preserves. Univ. Calif. Publ. Entomology 99: 1-161.

Arnold, R.A., P. Couch, and K.H. Osborne. 1994. "Smith's Blue Butterfly," pp. 424-425 in Life on the Edge: A Guide to California's Endangered Natural Resources (C.G. Thelander & M. Crabtree, eds.). BioSystems Books, Santa Cruz, CA.

Black, S.H., and D.M. Vaughan. 2005. "Species Profile: Euphilotes enoptes smithi", in Red List of Pollinator Insects of North America (M.D.Shepherd, D.M. Vaughan & S.H. Black, eds). CD-ROM Version 1 (May 2005). The Xerces Society for Invertebrate Conservation, Portland, OR:

Mattoni, R.H.T. 1955. Notes on the genus Philotes: I. Descriptions of three new subspecies and a synoptic list. Bull. S. Calif. Academy Sciences 53:157-165. 

Mattoni, R.H.T. 1977. The Scolitantidini. Part 1. Two new genera and generic rearrangement (Lycaenidae). J. Research Lepidoptera 16:223-242. 
(Available from http://www.doylegroup.harvard.edu/carlo/JRL/16/table_16D.html) 

Powell, J.A. 1981. Endangered habitats for insects: California coastal sand dunes. Atala 6:41-55. 

Pratt, G. F. and J. F. Emmel. 1998. "Revision of the Euphilotes enoptes and E. battoides complexes (Lepidoptera: Lycaenidae), pp. 207-270 in Systematics of Western North American Butterflies (T.C. Emmel, ed). Mariposa Press, Gainsville, FL.

PHOTOS: All photos are © 2006 Don Roberson; all rights reserved.

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