Geographic Range
Blue dotted butterflies are found in the United States west of the Mississippi River
and in Canada (Miller 1992). Populations tend to occur sporadically in conjunction
with their host plant,
Eriogonum compositum
, a wild buckwheat (Peterson 1997).
Habitat
Euphilotes enoptes
is intimately associated with its host plants, where both it and the plants live
in different elevations of the same geographic region (Peterson 1995). Within this
region they tend to live in sun-exposed rocky or sandy flats or slopes in foothills,
mountains, desert, and along coast (Opler, 2001).
- Habitat Regions
- temperate
- Terrestrial Biomes
- desert or dune
- chaparral
- mountains
Physical Description
Eggs – The eggs are a pale bluish-green color that eventually turns white.
Larvae – The larvae vary among the subspecies in color from ivory white to yellow to brown.
Pupa – Among the subspecies the pupa also vary in color, ranging from brown to yellowish-brown to translucent yellow. (Scott 1986)
Adults – The appearance of adults varies with the geographic region. The upperside
of the male is lilac blue surrounded by darker borders while the female tends to be
brown with an orange spot or patch on the hindwing. Both sexes have similar undersides,
typically off-white with brown spots. The black dots on the forewing are predominantly
larger and more square-like than those of the hindwing with an orange band on the
hingwing separated into dashes. (Opler, 2001)
- Other Physical Features
- ectothermic
- heterothermic
- bilateral symmetry
- Sexual Dimorphism
- sexes colored or patterned differently
Development
The development of blue dotted butterflies contains four main stages. The first stage
is the egg, which is laid on the host plant. The second stage is the larvae that
hatch from the eggs. The larvae then eat the flowers and developing seeds of the
host plant in order to prepare for the formation of the pupa.
Euphilotes enoptes
leave the host plant and pupate at the base of the plant, usually in the soil or
litter below it. When they emerge as adults, they continue the life cycle on and
around the host plant (Peterson 1995).
- Development - Life Cycle
- metamorphosis
Reproduction
The host plant is central to the reproduction process as males search around the host
plant for females. During courtship males land after females, and both contact each
other and flutter their wings before they copulate (Scott 1986). The female then
oviposits, or lays, the eggs on the flowers and buds of newly opened inflorescences,
where they will hatch into larvae that will then eat the flowers and their developing
seeds. It is because of this that the window for reproduction is so small; if there
were no flowers for the larvae to eat they would die and the attempt at reproduction
would be unsuccessful (Peterson 1995).
- Key Reproductive Features
- seasonal breeding
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
- fertilization
- oviparous
Lifespan/Longevity
Adults have a short life span that is typically two to nine days long (Peterson 1995).
Behavior
Males tend to "patrol" the host plant to seek females with whom they mate (Scott 1986).
Food Habits
The larvae feed on the developing seeds, young fruit, and flowers of the host plant
(Peterson 1995). Adults sip the nectar of flowers (esp. host flowers) and mud (Scott
1986). It is obvious that the host plants are essential to the feeding habits of
blue dotted butterflies.
- Plant Foods
- seeds, grains, and nuts
- fruit
- flowers
Ecosystem Roles
The caterpillars have a honey gland which secretes a sugary solution that
ants
eat.
Conservation Status
Due to the destruction of its habitat in California, the subspecies
Euphilotes enoptes smithi
was placed on the Endangered Species List in 1984 (Sbordoni and Forestiero 1998).
Additional Links
Contributors
Matthew Wund (editor), University of Michigan-Ann Arbor.
Sarah Raison (author), Southwestern University, Stephanie Fabritius (editor), Southwestern University.
- Nearctic
-
living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- temperate
-
that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).
- desert or dunes
-
in deserts low (less than 30 cm per year) and unpredictable rainfall results in landscapes dominated by plants and animals adapted to aridity. Vegetation is typically sparse, though spectacular blooms may occur following rain. Deserts can be cold or warm and daily temperates typically fluctuate. In dune areas vegetation is also sparse and conditions are dry. This is because sand does not hold water well so little is available to plants. In dunes near seas and oceans this is compounded by the influence of salt in the air and soil. Salt limits the ability of plants to take up water through their roots.
- chaparral
-
Found in coastal areas between 30 and 40 degrees latitude, in areas with a Mediterranean climate. Vegetation is dominated by stands of dense, spiny shrubs with tough (hard or waxy) evergreen leaves. May be maintained by periodic fire. In South America it includes the scrub ecotone between forest and paramo.
- mountains
-
This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.
- ectothermic
-
animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature
- heterothermic
-
having a body temperature that fluctuates with that of the immediate environment; having no mechanism or a poorly developed mechanism for regulating internal body temperature.
- bilateral symmetry
-
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
- metamorphosis
-
A large change in the shape or structure of an animal that happens as the animal grows. In insects, "incomplete metamorphosis" is when young animals are similar to adults and change gradually into the adult form, and "complete metamorphosis" is when there is a profound change between larval and adult forms. Butterflies have complete metamorphosis, grasshoppers have incomplete metamorphosis.
- seasonal breeding
-
breeding is confined to a particular season
- sexual
-
reproduction that includes combining the genetic contribution of two individuals, a male and a female
- fertilization
-
union of egg and spermatozoan
- internal fertilization
-
fertilization takes place within the female's body
- oviparous
-
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
- motile
-
having the capacity to move from one place to another.
- sedentary
-
remains in the same area
- herbivore
-
An animal that eats mainly plants or parts of plants.
- folivore
-
an animal that mainly eats leaves.
- frugivore
-
an animal that mainly eats fruit
- granivore
-
an animal that mainly eats seeds
References
Miller, J. 1992. The Common Names of North American Butterflies . Washington: Smithsonian Institution Press.
Opler, P.A., 2004. "Butterflies of North America -- Euphilotes Enoptes" (On-line). Accessed October 4, 2001 at http://www.npwrc.usgs.gov/resource/distr/lepid/bflyusa/usa/236.htm .
Peterson, M. 1997. Host Plant Phenology and Butterfly Dispersal: Causes and Consequences of Uphill Movement. Ecology , V. 78: 167-180.
Peterson, M. 1995. Phenological Isolation, Gene Flow, and Developmental Differences Among Low- And High-Elevation Populations of *Euphilotes enoptes* (Lepidoptera: Lycaeidae). Evolution , V. 49: 446-455.
Sbordoni, V., S. Forestiero. 1998. Butterflies of the World . Buffalo: Firefly Books.
Scott, J. 1986. The Butterflies of North America A Natural History and Field Guide . Stanford: Stanford University Press.
2002. "euphilot enoptes frames" (On-line). Accessed 12/13/04 at http://imnh.isu.edu/digitalatlas/bio/insects/insefr.htm .