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.

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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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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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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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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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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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
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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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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American Dagger Moth Caterpillar
A pale, sulfur-yellow to cream fuzzball bristling with dense tufts of hair and long black 'pencils' projecting from both ends, the American dagger moth caterpillar is one of the most recognizable hairy caterpillars on hardwood trees in fall.
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Gypsy Moth Caterpillar (Spongy Moth)
A bristly, blue-and-red-spotted caterpillar that can strip entire hardwood forests bare during major outbreak years.
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Giant Leopard Moth Caterpillar
A jet-black, bristly caterpillar that curls into a tight ball to reveal bright red-orange bands between its segments when disturbed.
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Southern Flannel Moth (Puss Caterpillar Moth)
A small, densely furred tan-to-orange moth best known for its unusual larva, a soft-looking, cat-tailed caterpillar whose fluffy coat hides rows of venomous spines.
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Hag Moth Caterpillar (Monkey Slug)
One of the strangest caterpillars in North America, with curling, hair-covered arm-like projections that make it look uncannily like a tiny tuft of matted fur or a miniature spider monkey.
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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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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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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
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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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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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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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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Milkweed Tussock Caterpillar
Rows of dense orange, black, and white hair tufts run down the back of this milkweed specialist, whose young larvae feed in tight groups that skeletonize milkweed leaves before dispersing to feed alone.
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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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Pipevine Swallowtail Caterpillar
A dark, velvety caterpillar studded with fleshy orange-tipped tubercles that feeds exclusively on pipevine, storing its host plant's chemistry for later defense as a butterfly.
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Spicebush Swallowtail Caterpillar
A bulging-eyed green caterpillar that lives folded inside its own silk-stitched leaf tent, looking every bit like a miniature snake peering out from cover.
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