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.

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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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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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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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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Eastern Black Swallowtail Caterpillar
A striking green-and-black banded caterpillar dotted with yellow spots that flashes a bright orange forked horn when disturbed.
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Bird Mite
A minute, pale to reddish mite that lives among feathers and nesting material of wild and domestic birds, sometimes dispersing into nearby buildings when nests are abandoned.
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Puss Moth
A stout, furry gray-and-white moth named for its dense, cat-like coat of hair, best known for its bizarre green caterpillar with a hump-backed, face-like front end and forked tail filaments used in defensive displays.
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Maggot
A pale, legless, tapering grub that wriggles through rotting food and organic waste, the larval stage of a fly.
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Firebrat
A fast, wingless, mottled gray-brown insect with long antennae and tail bristles that thrives in the warm, humid corners near ovens, boilers, and pipes.
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Common House Fly
A dull gray fly with four dark stripes down its back, the house fly is one of the most familiar insects on Earth, following people and their food waste to every continent.
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House Fly
A gray, fuzzy-bodied fly with four dark stripes on its thorax and large reddish compound eyes, famous for its erratic buzzing flight and tendency to land repeatedly on food and surfaces.
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Common Housefly
A dull gray fly with four dark stripes on its thorax and large reddish eyes, one of the most widespread insects on Earth thanks to its close association with human food and waste.
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Silverfish Firebrat
Two closely related, wingless, silvery or mottled insects with fish-like darting movements and three long tail bristles, one favoring damp basements and the other thriving near warm ovens and furnaces.
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Underwing Moth
A master of camouflage whose bark-patterned forewings hide brightly colored, banded hindwings that flash into view only when the moth is disturbed in flight.
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Fall Webworm
A pale, hairy caterpillar that spins loose, messy silk webs enclosing entire leaf clusters at the tips of tree branches, becoming especially noticeable in late summer and fall.
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