Lycaena rubidusruddy copper

Geographic Range

Lycaena rubidus is found only in the United States and Canada. It can be spotted in the region that spreads from British Colombia and east to North Dakota. It is also found in south to central California and Northern New Mexico. (Miller, 1992; Opler, 2004; Safra, 1998)


Ruddy coppers live in sandy or dry, gravelly areas such as scrub, dry fields, prairies, arid streams, and alluvial washes. (Opler, 2004; Scott, 1986)

Physical Description

Lycaena rubidus has a wingspan of 2.9 - 4.1 cm. The upperside of the male is bright red-orange, and the upperside of the female is a duller orange-brown to dark brown. The hindwings of both sometimes exhibit muted black spots. The undersides of both male and female are gray-white to gray-yellow. (Grzimek, 1972; Opler, 2004; Scott, 1986)

  • Sexual Dimorphism
  • sexes colored or patterned differently
  • Range wingspan
    2.9 to 4.1 cm
    1.14 to 1.61 in


Ruddy coppers go through four main life stages on their way to becoming a butterfly: the egg, the caterpillar (larva), the chrysalis (pupa), and finally the butterfly (adult).


Ruddy coppers go through four main life stages on their way to becoming a butterfly: the egg, the caterpillar (larva), the chrysalis (pupa), and finally the butterfly (adult). In order for this process to begin, however, the butterflies must mate. These butterflies, like all butterflies, reproduce sexually. A male Lycaena rubidus waits for the females along streams and in meadows in order to mate. The female butterfly produces white eggs that she lays singly at or near the base of the host plant, which will be a ruddy copper's food source once it enters the caterpillar stage. The mother distinguishes this host plant from others by not only the odor given off by the plant, but also by testing the leaves of the plant with receptors on her feet, antenae, or the tip of her abdomen. The eggs will hibernate there until the environmental conditions are right, then a caterpillar will emerge. The caterpillar is brown with a dark-reddish mid-dorsal band that is edged by yellow. They are shaped like pill bugs with highly arched backs, a flat ventral surface, short legs, and the head hidden beneath the thorax. After the caterpillar has obtained enough nutrients to sustain it through its next stage, it is taken by red ants to a nest in which it enters in to the chrysalis stage. Lycaena rubidus is inactive during the chrysalis stage and avoids predation by using camouflage. During the last portion of the chrysalis stage, the cocoon becomes translucent and shows the colors of the butterfly. Shortly after this, the butterfly emerges from the cocoon as a full adult, ready to mate and continue the life cycle. (Holland, 1898; O'Toole, 1986; Scott, 1986)

Beyond developing and laying eggs, butterflies give no parental care.

  • Parental Investment
  • pre-fertilization
    • provisioning


Lycaena rubidus has one flight from mid-June through July at low latitudes and from mid-July through August for latitudes.

The caterpillar secretes a sugary fluid from many small glands in its body wall. This fluid attracts red ants, which begins a mutualistic relationship between caterpillar and ant. The caterpillar provides the red ants with sugary food and the ants protect the caterpillar from predators. They also take the caterpillar to a nest, which the ants have built, where it remains, through the pupa stage, until it becomes a butterfly in the spring. (Grzimek, 1972; Scott, 1986)

Communication and Perception

Female ruddy coppers use chemical cues to find appropriate host plants on which to oviposit.

Food Habits

Lycaena rubidus eats different foods while in its different life stages. As a larvae, or caterpillar, it feeds off of petals and bracts of flowers or upon delicate terminal leaves of the Dock (Rumex) species in the buckwheat family. The adult form, the butterfly, feeds off of flower nectar. (Holland, 1898; O'Toole, 1986; Opler, 2004)

  • Plant Foods
  • leaves
  • nectar
  • flowers

Ecosystem Roles

These butterflies are pollinators, herbivores, and prey for predators.

  • Ecosystem Impact
  • pollinates

Economic Importance for Humans: Positive

Lycaena rubidus, like all butterflies, helps in the pollination process for flowering plants. Butterfly watching has also become a very enjoyable nature activity. (O'Toole, 1986)

Economic Importance for Humans: Negative

Ruddy copper butterflies do not cause any harm to humans during the butterfly stage. However, during the larval stage they do consume the leaves of plants, which some humans may consider valuable. (O'Toole, 1986)

Conservation Status

Lycaena rubidus is generally not threatened, however, it may be rare in the periphery of its range. (Opler, 2004)


Matthew Wund (editor), University of Michigan-Ann Arbor.

Loren Watt (author), Southwestern University, Stephanie Fabritius (editor), Southwestern University.



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.

World Map

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.


uses smells or other chemicals to communicate

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.


humans benefit economically by promoting tourism that focuses on the appreciation of natural areas or animals. Ecotourism implies that there are existing programs that profit from the appreciation of natural areas or animals.


animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature


union of egg and spermatozoan


an animal that mainly eats leaves.


An animal that eats mainly plants or parts of plants.


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.

internal fertilization

fertilization takes place within the female's body


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.


having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.


an animal that mainly eats nectar from flowers


reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

scrub forest

scrub forests develop in areas that experience dry seasons.


reproduction that includes combining the genetic contribution of two individuals, a male and a female


uses touch to communicate


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).

tropical savanna and grassland

A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.


A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.

temperate grassland

A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.


uses sight to communicate


Grzimek, B. 1972. Grzimek's Animal Life Encyclopedia Volume 2: Insects. New York: Van Nostrand Reinhold Co..

Holland, W. 1898. The Butterfly Book. New York: Doubleday, Page and Company.

Miller, J. 1992. The Common Names of North American Butterflies. Washington and London: Smithsonian Institute Press.

O'Toole, C. 1986. Encyclopedia of Insects. New York: Facts on File Publications.

Opler, P. 2004. "Butterflies of Utah-- Lycaena rubidus" (On-line). Accessed 12/21/04 at

Safra, J. 1998. Encyclopedia Britannica Volume 2. Chicago: Encyclopedia Britannica Inc..

Scott, J. 1986. The Butterflies of North America. Stanford, California: Stanford University Press.