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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The cabbage looper (Trichoplusia ni) is a member of the moth family Noctuidae. The caterpillar, a measuring worm, is smooth and pale green with white stripes and is one of a many species called cabbage worm. It is called a "looper" because it arches its body as it crawls, inchworm-style. This species is very destructive to plants due to its voracious consumption of leaves. It is not restricted to cole crops; other plant hosts include tomato, cucumber and potato. The adult of the species is a nocturnal brown moth.
Trichoplusia ni is also used as an expression system in the field of molecular biology.