Page 556 - The Book of Caterpillars: A Life-Size Guide to Six Hundred Species From Around the World

MOTH CATERPILLARS

FAMILY Erebidae
DISTRIBUTION North America, from southern Canada and Maine,
south to Florida, and west to Texas
HABITAT Fields and roadside edges
HOST PLANTS Milkweed (Asclepias spp.) and dogbane (Apocynum spp.)
NOTE Gregarious caterpillar commonly encountered throughout
most of its range
CONSERVATION STATUS Not evaluated, but globally secure, although possibly rare
at the peripheries of its range

ADULT WINGSPAN
1¼–1 ⁄ in (32–43 mm)
CATERPILLAR LENGTH

1⅜ in (35 mm)
EUCHAETES EGLE
MILKWEED TUSSOCK
554
(DRURY, 1773)

The Milkweed Tussock caterpillar, which hatches from a mass
of eggs laid on the underside of leaves, is visually unique. While
early instars are slightly hairy and gray, later instars, at first
glance, look more like a dust mop or pile of discarded yarn than
a life form. The larvae are social feeders until the end of the
third instar. Early instar larvae feed by skeletonizing leaves, and
older caterpillars have developed the trait of pre-severing leaf

veins to reduce the sap ow of toxic glycosides. A large colony
of these caterpillars can quickly defoliate an entire milkweed
(or dogbane) plant and, unlike Monarch caterpillars (Danaus
plexippus) and other milkweed feeders, prefer mature plants over
younger, more succulent plants.

As a defense when threatened, the caterpillars freeze in place,
then slightly curl their bodies and drop from the host plant into
the leaf litter below. In addition, both caterpillars and adult
The Milkweed Tussock caterpillar is densely Milkweed Tussock moths are also chemically protected by
tufted. Its blackish-gray abdomen sports multiple the milkweed toxins the larvae ingest. Two generations per year
white and black lashes, predominantly along the
thoracic and anterior regions. Orange-brown are typical throughout all but the far northern fringe of their
tufts of setae on the dorsum are curled upward
and meet along the centerline. The head is black. range. The species is also known as the Milkweed Tiger Moth.

Actual size