Page 273 - The Book of Caterpillars: A Life-Size Guide to Six Hundred Species From Around the World

BUTTERFLY CATERPILLARS

FAMILY Nymphalidae
DISTRIBUTION Canada (southern Yukon, Northwest Territories, and British
Columbia), and northern and western United States
HABITAT Many habitats, from sea level up to 8,200 ft (2,500 m) elevation,
including canyons, open deciduous woodlands, watercourses,
parks, and gardens
HOST PLANTS Nettle (Urtica spp.) and hop (Humulus spp.)
NOTE Spiny, white caterpillar that builds an open-ended leaf nest
CONSERVATION STATUS Not evaluated, but common

ADULT WINGSPAN
2–2⅛ in (50–55 mm)
CATERPILLAR LENGTH
1 ⁄ –1⅜ in (30–35 mm)

POLYGONIA SATYRUS
SATYR COMMA 271
(W. H. EDWARDS, 1869)

Satyr Comma eggs are laid on the underside of nettle leaves—
sometimes up to seven eggs may hang down in a string from

one leaf. The young caterpillars emerge after ve to seven days,
and early instars are usually solitary, resting in the open on the
underside of a leaf. The larvae build individual nests by folding
the edges of a nettle leaf and loosely silking them together. The
ends are left partially open, so the caterpillar is visible inside.
Caterpillars feed either from the leaf edge or at midleaf, making
deep, jagged holes.

Concealment is this species’ principal means of defense, although
natural enemies such as small predatory bugs—for example,
Anthocoridae—may enter the nests. Caterpillar development
is rapid, taking just 23 days to reach pupation. Only nine days
are spent as a pupa, and the adults overwinter and may live for

up to 12 months. Both sexes visit owers for nectar, but males
may also feed on animal scat and mud.

The Satyr Comma caterpillar is almost
entirely white dorsally, and most of the spines
are white. The anterior horns are small, black,
and antler-like. Black chevrons interrupt the
white dorsum, one per segment. Laterally,
Actual size the caterpillar is black, and the black spiracles
are encircled in white.