Page 489 - The Book of Caterpillars: A Life-Size Guide to Six Hundred Species From Around the World

MOTH CATERPILLARS

FAMILY Geometridae
DISTRIBUTION North America, Europe, and across Asia
HABITAT Deciduous and mixed woodlands
HOST PLANTS Various trees, including Alder (Alnus glutinosa), birch (Betula
spp.), elm (Ulmus spp.), maple (Acer spp.), walnut (Juglans spp.),
and willow (Salix spp.)

NOTE Superbly camou aged caterpillar that is often overlooked
CONSERVATION STATUS Not evaluated

ADULT WINGSPAN
1⅜–2⅜ in (35–60 mm)

CATERPILLAR LENGTH
2⅜–2¾ in (60–70 mm)
BISTON BETULARIA
PEPPERED MOTH 487

LINNAEUS, 1758

The female Peppered Moth lays up to 600 yellow eggs, singly,
either in bark crevices or on leaves. The caterpillar is a twig
mimic; the slender shape and colors of green and brown provide

it with excellent camou age when at rest during the day. The
caterpillars move to the ground to pupate, and they overwinter
within a cocoon in the soil or in leaf litter. The adults emerge in
late spring and early summer. There is usually one generation,
with the adults on the wing from April to September.

This is a polymorphic species that has been the subject of
research into natural selection, as there are two main adult The Peppered Moth caterpillar looks like a
color forms. The mottled form offers camouflage when the stick. The head is chestnut brown, as are the
legs. The body is mostly green, broken up with
moth rests on bark covered with lichens and mosses, while regular bands of gray brown. The spiracles are
the melanic or black form equips the moth with camouflage also edged in brown. There are small warts and
projections to enhance its twiglike appearance.
when resting on pollution-darkened bark—an adaptation
known as industrialized melanization. However, with decreases
in air pollution, the melanic form is now rare.

Actual size