Bug Identifier

Bug Encyclopedia

Search and identify bugs & insects — beetles, butterflies, moths, ants, bees, spiders and more — with size, habitat, danger, behavior, and how to tell them apart.

Cutworm

A plump, dull gray-brown caterpillar that hides in soil by day and emerges at night to sever young seedlings at the base, curling tightly into a C-shape when disturbed.

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Armyworm

Armyworm

A striped, greenish-brown caterpillar that gets its name from its habit of migrating in dense, destructive groups across grass and grain fields.

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Gypsy Cutworm Moth

A plain, mottled grey-brown night-flying moth whose stout, soil-dwelling larvae are known as cutworms for their habit of severing young plant stems near ground level.

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Fall Armyworm

Fall Armyworm

A brownish-green caterpillar marked with a pale inverted "Y" on its head, notorious for rapid, large-scale outbreaks that devastate corn and other grass crops across the globe.

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Armyworm Moth

Armyworm Moth

A plain tan to reddish-brown moth whose caterpillars are famous for marching in large groups across fields, stripping grasses and grain crops as they move.

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Caterpillar

The soft-bodied, segmented larval stage of butterflies and moths, recognized by its worm-like shape, multiple pairs of stubby legs, and voracious appetite for leaves.

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Tent Caterpillar

A social, blue-striped caterpillar that builds a conspicuous silken tent in the fork of a tree branch, sheltering large colonies of siblings that emerge together to feed on leaves.

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Saddleback Caterpillar

Saddleback Caterpillar

An unmistakable stout caterpillar with a bright green saddle-shaped patch on a brown back, bristling with clusters of spines along its stocky body.

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Puss Caterpillar

Puss Caterpillar

A caterpillar disguised as a tuft of soft fur, its dense coat of silky hairs conceals rows of spines beneath, making it one of the most deceptively harmless-looking stinging caterpillars in North America.

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Monarch Caterpillar

A boldly banded caterpillar in white, yellow, and black stripes, unmistakable as it munches its way through milkweed leaves before transforming into North America's most famous migratory butterfly.

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Woolly Bear Caterpillar

Woolly Bear Caterpillar

A densely bristled caterpillar banded in black at both ends with a rusty-orange middle section, famous in folklore for supposedly predicting winter severity and for rolling into a tight ball when touched.

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Stinging Rose Caterpillar

Stinging Rose Caterpillar

A boldly striped slug caterpillar in candy-like tones of yellow, orange, and purple, crowned with tufted spine clusters that can sting on contact.

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Tussock Moth Caterpillar

A boldly tufted caterpillar bristling with dense brush-like hair tussocks and long dark pencil plumes that give it an almost punk-rock silhouette.

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Tiger Swallowtail Caterpillar

A smooth green caterpillar with a swollen thorax marked by two large fake eyespots, giving it an uncanny resemblance to a tiny snake's head.

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Question Mark Caterpillar

A spiny, variably colored caterpillar named for the silver question-mark-shaped mark on the underside of the adult butterfly's wings.

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Polyphemus Moth Caterpillar

A plump, apple-green giant silk moth larva with rows of silvery spots that swells to the size of a large finger before spinning a papery brown cocoon.

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Mourning Cloak Caterpillar

A gregarious, velvety black caterpillar speckled with white dots and a striking row of brick-red spots down its back, often seen feeding in clusters on willow branches.

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Luna Moth Caterpillar

Luna Moth Caterpillar

A large, plump, apple-green caterpillar with faint yellow side stripes and rows of small red-orange tubercles, the larval form of one of North America's most beautiful giant silk moths.

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Gulf Fritillary Caterpillar

Gulf Fritillary Caterpillar

A vivid burnt-orange caterpillar bristling with rows of branched black spines that specializes almost exclusively on passionflower vines.

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Forest Tent Caterpillar

Named for the silk mats rather than tents it spins, this blue-gray caterpillar sports a row of pale keyhole- or footprint-shaped spots down its back and can appear in outbreak numbers that strip entire stands of trees bare.

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Grape Leaffolder Caterpillar

Grape Leaffolder Caterpillar

This small green caterpillar stitches grape leaves together with silk into a rolled shelter, feeding hidden inside its own leafy tube and leaving skeletonized patches behind.

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Io Moth Caterpillar

Io Moth Caterpillar

A bright lime-green caterpillar bristling with clusters of branching, stinging spines and thin red and white racing stripes along its sides.

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Buck Moth Caterpillar

Buck Moth Caterpillar

A dark, spiny caterpillar covered in branched spines that marches across oak-lined sidewalks in dense groups each spring.

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Black Swallowtail Caterpillar

A striking green caterpillar banded with black and dotted with yellow spots, famous for the bright orange, forked osmeterium it flicks out when disturbed.

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