Family:Lycaenidae
Family
Description:
Alternate Common Names:Orange-Bordered
Blue, Karner Blue.
Note: This species is referred to with the
genus name Plebejus by some authors.
Range:
This species ranges from central Canada, south through most of the western half
of the U.S., and east through the Great Lakes states to New Hampshire. It occurs
throughout Idaho.
Habitat:
In the west it occurs in open areas such as meadows and prairies;
in the east, it occurs in sandy habitats.
Diet:
Caterpillar:
Caterpillars feed on the new leaves and flowers of a variety of legumes, including
lupines (Lupinus spp.), alfalfa (Medicago spp.), and milkvetch
(Astragalus spp.).
Adult:
Butterflies drink flower nectar.
Ecology:
The caterpillar is equipped with a honey gland, also known as a dorsal nectary
organ, which emits a sugary solution agreeable to ants. The ants feed on
the solution and in turn protect the caterpillar from predators. Also for protection,
the caterpillar bears a pair of everscible tubercles or tentacles
on the eighth segment. These tubercles are usually housed within the body, but
when the caterpillar feels threatened by the approach of a potential predator,
they can be pushed out to release a chemical which mimics an ant alarm pheromone. This scent causes the ants to become
frenzied and aggressive, and the potential predator takes leave or is eaten
by the ants. There are two generations of caterpillars each summer in the east,
and three in the west. Each caterpillar undergoes four stages of growth, called
instars. Either the egg overwinters, or
the newly hatched caterpillar overwinters in a physiological state called diapause. Adults generally
fly from April to
November.
Reproduction:
Males actively patrol
in search of receptive females. Females lay eggs by walking down the stem of
a host plant, ovipositing along the way and at the base
of the plant. The eggs are green with white ridges.
Conservation:
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Global Rank: | G5; most populations are widespread, abundant, and secure. One subspecies in New York, the Karner Blue (L. melissa samuelis), is ranked as T2, imperiled and vulnerable to extinction, and is protected. |
Ferris, C. D. and F. M. Brown. (eds.) 1981. Butterflies of the Rocky Mountain States. Univ. of Oklahoma Press, Norman, Oklahoma, USA, 442 pp.
Opler, P. A., H. Pavulaan, and R. E. Stanford. 1995. Butterflies of North America. Jamestown, North Dakota, USA: Northern Prairie Wildlife Research Center Home Page. http://www.npwrc.usgs.gov/resource/distr/lepid/bflyusa/bflyusa.htm (Version 05Nov98).
Opler, P. A. and A. B.Wright. 1999. A Field Guide to the Western Butterflies. Second Edition. Peterson Field Guide Series. Houghton Mifflin Company, New York, New York, USA, 540 pp.
Pyle, R. M. 1981. National Audubon Society Field Guide to North American Butterflies. Alfred A. Knopf, Inc., New York, New York, USA, 924 pp.
Scott, J. A. 1986. The Butterflies of North America. Stanford University Press, Stanford, California, USA, 583 pp.
Stanford, R. E. and P. A. Opler. 1993. Atlas of Western U.S.A. Butterflies (Including Adjacent Parts of Canada and Mexico). Published by authors, Denver, Colorado, USA, 275 pp.