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.

Flea

Flea

A tiny, wingless, laterally flattened insect built for moving swiftly through fur, famous for its powerful hind legs that allow it to leap many times its own body length.

other
Water Flea

Water Flea

Despite the name, the water flea is not an insect at all but a tiny, jerky-swimming crustacean whose transparent body and single dark eye make it one of the most recognizable members of freshwater plankton.

other
Flea Beetle

Flea Beetle

A tiny, shiny beetle that springs away like a flea when disturbed, leaving characteristic small round holes peppered across the leaves it feeds on.

beetle
Springtail

Springtail

A minuscule, wingless hexapod best known for its spring-loaded tail-like structure that flicks it into sudden, erratic hops when disturbed, often found in huge numbers in damp soil and leaf litter.

other
Caterpillar

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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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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Tent Caterpillar

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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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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Monarch Caterpillar

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.

caterpillar-larva
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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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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Gypsy Moth Caterpillar

Gypsy Moth Caterpillar

A hairy, mottled gray caterpillar marked with rows of paired blue and red dots down its back, notorious for periodic outbreak years that can strip entire forests bare.

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Forest Tent Caterpillar

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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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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Spiny Oak-slug Caterpillar

Spiny Oak-slug Caterpillar

A tiny, flattened slug-shaped caterpillar in shades of green, orange, or purple, bristling with clusters of branched spines that can deliver a sting if handled.

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Cabbage White Caterpillar

Cabbage White Caterpillar

A velvety, bright green caterpillar with a faint yellow stripe down its back, the larval stage of the common white butterfly seen fluttering around vegetable gardens.

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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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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

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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Cecropia Moth Caterpillar

Cecropia Moth Caterpillar

North America's largest native caterpillar, a bulky blue-green giant studded with rows of bright red, yellow, and blue knobby tubercles resembling tiny coral formations.

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Eastern Tent Caterpillar

Eastern Tent Caterpillar

A fuzzy, blue-flecked caterpillar with a pale stripe down its back, famous for spinning large communal silk tents in the forked branches of cherry and apple trees each spring.

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Painted Lady Caterpillar

Painted Lady Caterpillar

A spiky, mottled caterpillar that spins loose silk webbing over thistle or mallow leaves and hides inside its own protective tent while feeding.

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Mourning Cloak Caterpillar

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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Question Mark Caterpillar

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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