Page 535 - The Book of Caterpillars: A Life-Size Guide to Six Hundred Species From Around the World

MOTH CATERPILLARS

FAMILY Notodontidae
DISTRIBUTION North America
HABITAT Deciduous woodlands and forests, parks, and gardens
HOST PLANTS Various trees and shrubs, including Alder (Alnus glutinosa),
birch (Betula spp.), hawthorn (Crataegus spp.), poplar
(Populus spp.), and willow (Salix spp.)

NOTE Cleverly camou aged caterpillar that squirts acid if disturbed
CONSERVATION STATUS Not evaluated

ADULT WINGSPAN

⁄ –1⅜ in (24–35 mm)
CATERPILLAR LENGTH
1 ⁄ in (30 mm)
SCHIZURA UNICORNIS
UNICORN CATERPILLAR 533

(J. E. SMITH, 1797)

Female Unicorn moths lay small, round eggs on the underside
of leaves of the host plant. They hatch into odd-looking
caterpillars that are active from May to October. The larvae
then drop to the ground, where they spin a protective cocoon
in the leaf litter. This species overwinters as a caterpillar and
pupates within its cocoon in spring. The adult moths are on the
wing from February to September in the more southerly zones
of their range and May to August in the north. There is a single
generation each year.

The Unicorn gets its name from the appearance of the caterpillar.

It has a large horn on the rst abdominal segment, and is also
equipped with a cervical gland from which it squirts formic acid,
if disturbed. The horn, together with the disruptive coloration
created by the green band across the thorax, provide excellent

camou age. The adult moth also relies on camou age, wrapping
its wings around its body to form a tube that looks like a piece
of broken twig.

The Unicorn Caterpillar has a mottled brown
body with two bright-green thoracic segments
and two faint, dark lateral lines. There is a Actual size
conspicuous, hornlike dorsal hump on the rst
abdominal segment and a much smaller one
on the eighth abdominal segment.