[3] Lycaena rubidus is found in only North America, spanning from British Columbia and California to South Dakota,[5][6] which is similar to the Blue copper.

While it is originally camouflaged to avoid predation, the chrysalis becomes transparent by the end of the cycle, and the colors of the butterfly can be seen through the membrane.

[5] After mating, female L. rubidus spend the rest of their lives (about two weeks) searching for the correct food plants and laying eggs.

[4] They use scent, as well as the receptors on the tips of their feet, abdomen, and antennae to ensure that they are laying their eggs on the correct plant.

[4] Females are not territorial, and will not care for their young beyond laying them on a host plant that will be the larval food source once the eggs hatch.

[5] The ruddy copper's eyes, like their wings, are sexually dimorphic, and females can see a broader range of color than males.

[10] The dorsal region on the female ruddy copper eye contains pigments P360, P437, and P568, which are sensitive to ultra-violet, blue, and red wavelengths respectively.

[4] The ventral eye of both sexes lacks the blue-sensitive P437 pigment, but contains P360, P500 (green), and P568, all of which are colors that are important for ruddy coppers to see on the ground.

[4] Male L. rubidus are selectively territorial, and will defend perches around streams and meadows where they will wait for females.

[9][4] The dorsal region of female L. rubidus eyes are trichromatic, containing P568, which allows them to judge the red-orange of the male's wing color.

[5] The caterpillars secrete a fluid through glands in the body wall that has a high sugar concentration, which attracts the red ants.