Family:Lycaenidae
Family
Description:
Alternate Common Name: Tailed Blue.
Range:
This species is found east of the Rockies, from southern Canada to Central America.
It may also occur in patches in the intermountain west and southwestern U.S.
Eastern-tailed blues occur in isolated sections of northern and west central
Idaho.
Habitat:
Adults occur in open areas, particularly those recently disturbed.
Diet:
Caterpillar:
Caterpillars feed on the buds, flowers, seeds, and sometimes leaves of legumes, including
species of clover (Trifolium spp.), alfalfa (Medicago spp.), pea
(Lathyrus spp.), vetch (Vicia spp.), and bean (Phaseolus
spp.).
Adult:
Butterflies obtain nectar from relatively short plants with open, shallow
flowers, such as wild strawberry (Fragaria spp.) and white sweet clover
(Melilotus alba).
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. Caterpillars overwinter within
the pods of host plants
in a physiological state called diapause,
and pupate in the
spring. Each year, there are three generations in the northern part of its range
and many generations in the south; in the case of multiple generations during
a given summer, only the caterpillars of the last generation overwinter. Each
caterpillar undergoes four stages of growth, called instars.
Adults generally fly
from March to December. This is one of the few members of the family Lycaenidae
that can be found resting with its wings open.
Reproduction:
Males patrol
near host plants for receptive females. Females lay eggs on flower buds and
stems.
Conservation:
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Global Rank: | G5; populations are widespread, abundant, and secure. |
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.