Explanation of Names
The proper name for this butterfly is debated. The name hyllus is the older name, but it was originally described as from Smyrna, Turkey, meaning it can not be the same species as found in North America (out species is not found there, and no similar species native to Turkey is found also in North America). The name Lycaena thoe was given to a North American insect originally, and was used for many years for out insects. However, the name L. hyllus was occasionally thought perhaps the same, and F. Martin Brown and W.D. Field "officially" replaced the name L. thoe with the name L. hyllus in 1970. Since that time the name L. hyllus has been more often (though not always used), and this use has been considered to be incorrect, improper, and "illegal" by several authors. In 2010, Calhoun reinforced the American usage of the name hyllus by designating a "neotype" to define (or redefine) the name Papilio hyllus; using a female specimen collected in Brooklyn, New York. This is the usage followed by most current authors, but it may yet be overturned, and the name Lycaena thoe may eventually become the "winner" in this debate.
European authors consider the name Papilio hyllus Cramer, to be an invalid (preoccupied) name, and a synonym of the Eurasian species Lycaena thersamon (Esper), 1784 [but, preoccupied by what?].
One of the easiest Coppers to recognize. Size is large for a Copper. Underside of all wings is scattered with prominent small rounded black spots. Front wings below are light orange, paler toward the margins; hind wings below are pale gray (nearly white) with a broad orange band near the margin. The upper sides of hind wings on both males and females are dark dull brownish with the same wide orange submarginal band as below strongly developed. Above, males are entirely dark, and when fresh have a reflective brassy sheen (looks purple from some angles). Females have the front wings above light brownish orange with prominent black spots and a wide dark outer borders. On both surfaces, the lowermost black pair of spots (may be fused into one elongate spot) in the postmedian series on the front wings is usually distinctly offset toward the base as compared to spots above it (occasionally almost in line).
Widespread from the east base of the Rocky Mountains, to the Atlantic across southern Canada and the United States. Mostly absent from southern/coastal regions from North Carolina to Texas. Also recorded from lower elevations along the Pacific Slope of the Rockies in Utah, Colorado, Wyoming, Idaho, and Montana.
Moist open sunny areas, often low-lying pockets, near water, where larval host plants, Docks and/or Knotweeds (Rumex and Polygonum species) are common.
Through most of range there are two adult flights, one in late spring/early summer and one in late summer/autumn. In coolest northern areas there may be only one flight, in summer. In mildest southern areas there are three flights, roughly in spring, summer, and autumn.
Butterflies and Moths of North America
live adult images, US distribution map, and species account
'A Catalogue of the Butterflies of the United States and Canada'
by Jonathan P. Pelham, 2011 [see discussion under entry number 415]
Butterflies of Canada
pinned adult images, Canadian distribution map, and species account