looper, name for caterpillars that move with a looping motion, including the inchworm and the cabbage looper.

cabbage looper, moth larva, Trichoplusia ni, that feeds by night on the leaves of cabbage and related plants and is a serious agricultural pest. Like the inchworms (of another moth family), cabbage loopers lack walking appendages in the middle of the body and progress by drawing the rear end up to the front end and then straightening. A cabbage looper has a smooth green body with a white stripe along each side and reaches a length of 11/4 in. (3.2 cm). It pupates in a cocoon on the underside of a leaf. The adult moth is brown with a white spot on each wing. Cabbage loopers are classified in the phylum Arthropoda, class Insecta, order Lepidoptera, family Noctuidae.

or cankerworm or inchworm

Larva of any member of a large, widespread group (mostly in the family Geometridae, with some in the family Noctuidae) of moths. Loopers move in a characteristic “inching” or “looping” gait by extending the front part of the body and bringing the rear up to meet it. Resembling twigs or leaf stems, they feed on foliage, and can seriously damage or destroy trees.

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Distinctive green, white-lined larva, or caterpillar (Trichoplusia ni), of the owlet moth family (Noctuidae). Like other loopers, it moves in an “inching” motion. It is an economic pest of cabbages and associated crops, particularly in the U.S. and Europe. The adults, known as Ni moths, migrate considerable distances. They are mottled brown with a pale Y-shaped mark on each forewing. The typical adult wingspan is about 1 in. (25 mm).

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