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.

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
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
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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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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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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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
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
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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Zebra Longwing Caterpillar
A creamy-white caterpillar dotted with black spots and armed with branching black spines, feeding exclusively on passionflower vines whose chemistry it stores for defense.
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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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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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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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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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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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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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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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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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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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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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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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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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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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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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