Page 639 - The Book of Caterpillars: A Life-Size Guide to Six Hundred Species From Around the World

MOTH CATERPILLARS

FAMILY Noctuidae
DISTRIBUTION North America, South America, Europe (except northern
Scandinavia), much of Africa, and across Asia to China, Japan,
Southeast Asia, and Malay Archipelago
HABITAT Diverse, including tropical, subtropical, and temperate
agricultural land
HOST PLANTS Crucifers such as Cabbage (Brassica oleracea) and relatives; Beet
(Beta vulgaris); cucurbits, such as watermelon (Citrullus lanatus);
and solanaceous plants, such as Potato (Solanum tuberosum),
Tomato (Solanum lycopersicum), and Tobacco (Nicotiana tabacum)
NOTE Looper caterpillar with distinctive vestigal prolegs on two
abdominal segments
CONSERVATION STATUS Not evaluated, but common

ADULT WINGSPAN
1 ⁄ –1½ in (33–38 mm)
CATERPILLAR LENGTH
1 ⁄ –1 ⁄ in (30–40 mm)
TRICHOPLUSIA NI
CABBAGE LOOPER 637

(HÜBNER, [1803])

Cabbage Looper caterpillars hatch from yellowish-white or
greenish eggs laid singly or in small groups on either side of a
leaf. In early instars, they feed on the lower leaf surface but in

the fourth and fth instars make large holes in the center of host
plant leaves. In cabbage, they can bore into the developing head,
damage seedlings, or feed on wrapper leaves. They can consume
three times their body weight daily, growing from egg to pupa in
as little as 20 days; in some locations, there are seven generations
per year. The fragile white cocoons are found under leaves,
in leaf litter, or in soil.

Adults may migrate as far as 125 miles (200 km) from their
breeding site; this, together with their polyphagous feeding,
accounts for the species’ extensive range. The caterpillars
damage cruciferous crops and may occasionally attack many
others. In addition to pesticides, their spread can be controlled
by their natural enemies—wasp parasitoids, such as Copidosoma
truncatellus, and tachinid ies, such as Voria ruralis. A nuclear

polyhedrosis virus can also kill more than 40 percent of a
caterpillar population.

The Cabbage Looper caterpillar is mostly
green but usually marked with a distinct white
stripe on each side. It is thin and long throughout
its development but becomes rather stout
posteriorly approaching pupation, although
remaining tapered toward the front end. It can
be distinguished from other loopers by the
Actual size vestigial prolegs located ventrally on abdominal
segments three and four (the fully developed
prolegs are on the fth, sixth, and last segments).