Page 166 - The Book of Caterpillars: A Life-Size Guide to Six Hundred Species From Around the World

BUTTERFLY CATERPILLARS

FAMILY Lycaenidae
DISTRIBUTION Northwestern United States, from Washington State to California
and east to Colorado and Montana
HABITAT Montane meadows and roadsides
HOST PLANTS Knotweed and smartweed (Polygonum spp.), and docks and sorrels
(Rumex spp.)
NOTE Slow-moving, cryptic caterpillar that produces fast-moving,

dazzling butterfly
CONSERVATION STATUS Not evaluated, but common

ADULT WINGSPAN
1–1³∕₁₆ in (25–30 mm)
CATERPILLAR LENGTH
¾ in (20 mm)
LYCAENA EDITHA
EDITH’S COPPER
164
(MEAD, 1878)

Edith’s Copper caterpillars hatch in late spring from
overwintering eggs and feed voraciously, completing their
development through four instars within three weeks. The
larvae feed only on leaves, grazing mostly on the lower surfaces,
eventually eating holes through them and later feeding on leaf
edges. No nests are built. The green caterpillars depend on
camouflage for protection, and attendance by ants is common,

aiding defense from predators and parasitoids. The pupae hatch
Actual size
in early summer, and there is a single generation annually.

The range of hosts used by Edith’s Copper is uncertain, and it
is possible that many other species in the Polygonaceae family

are utilized. The adults are strongly attracted to flowers such as
Yarrow (Achillea millefolium) and aster (Asteraceae), and males
aggressively guard low perches. Lycaena editha can be abundant

The Edith’s Copper caterpillar is bright green locally and may be expanding its range northward into Canada.
with small, white spots peppering the body. A It is related to a number of similar Lycaena species occurring in
distinct, middorsal, red line is present. There is
a dense covering of short, orange-brown setae high-elevation habitats.
on the body and the green head. The spiracles
are pink orange encircled in brown. Prior to
pupation the red stripe fades.