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.

Horse Fly Larva

Hidden in the wet mud along pond and stream margins, the horse fly larva is a tapered, tough-skinned predator that hunts other small soil and mud-dwelling invertebrates before eventually transforming into the familiar biting fly.

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Dobsonfly Larva (Hellgrammite)

A large, fierce-looking aquatic larva with strong pinching jaws and fringed side gills, spending years hunting under stream rocks before becoming a giant winged dobsonfly.

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Crane Fly Larva

Thick-skinned and worm-like, the crane fly larva, often called a leatherjacket, burrows through wet mud and decaying vegetation at the edges of ponds and streams, breaking down plant material as it grows.

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Black Fly Larva

Black Fly Larva

Anchored to submerged rocks in fast-flowing streams by a silken thread, the black fly larva bends into the current and combs the water for drifting particles with a pair of delicate, fan-shaped feeding brushes.

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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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Non-Biting Midge Larva (Bloodworm)

Wriggling through soft bottom mud in dense colonies, the bloodworm gets its striking red color from a specialized blood pigment that lets it survive in oxygen-poor water where few other insects can.

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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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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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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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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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Mourning Cloak Butterfly

Mourning Cloak Butterfly

A deep maroon-brown butterfly bordered with a cream-yellow band and a row of iridescent blue spots, unusual among butterflies for overwintering as an adult and being one of the first to appear in early spring.

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Cabbage White Butterfly

Cabbage White Butterfly

A small, plain white butterfly with one or two black spots on each forewing and dark wingtips, one of the most common and widespread garden butterflies in the world.

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Blue Morpho Butterfly

Blue Morpho Butterfly

A dazzling, hand-sized rainforest butterfly whose wings flash brilliant metallic blue in flight, an effect created not by pigment but by microscopic light-bending scales.

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Monarch's Milkweed

Monarch's Milkweed

A boldly orange-and-black true bug that shares milkweed plants with Monarch butterfly caterpillars, often clustering in large groups on seed pods and stems.

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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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