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.

Fall Armyworm
A brownish-green caterpillar marked with a pale inverted "Y" on its head, notorious for rapid, large-scale outbreaks that devastate corn and other grass crops across the globe.
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Armyworm
A striped, greenish-brown caterpillar that gets its name from its habit of migrating in dense, destructive groups across grass and grain fields.
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Armyworm Moth
A plain tan to reddish-brown moth whose caterpillars are famous for marching in large groups across fields, stripping grasses and grain crops as they move.
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Fall Webworm Moth
A plain white (sometimes lightly speckled) moth whose caterpillars are far more familiar than the adult, spinning large communal silk webs over the ends of tree branches in late summer and early autumn.
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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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Fireflies Larvae Glowworm
The larval form of fireflies, often called glowworms, are flattened, segmented crawlers that glow with a steady greenish light. These little predators hunt slugs, snails, and worms in damp ground.
beetle
Fishfly Larva
A flattened, armor-plated predator of stream bottoms, the fishfly larva spends one to three years underwater seizing prey with sickle-shaped jaws before briefly taking wing as a short-lived winged adult.
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Caddisfly Larva
A soft-bodied aquatic larva famous for building a portable protective case from sand, gravel, or plant debris bound together with silk.
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Alderfly Larva
Fringed with feathery gill filaments along its sides, the alderfly larva crawls through soft pond and stream sediments hunting smaller invertebrates before eventually leaving the water entirely to pupate on land.
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Mosquito Larva
A wriggling, comma-shaped aquatic larva that hangs from the water's surface to breathe before transforming into a flying adult mosquito.
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Codling Moth Larva
The classic 'worm in the apple,' this pinkish-white caterpillar tunnels straight to the core of apples and pears, leaving a telltale frass-plugged entry hole behind.
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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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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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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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Soldier Fly Larva
Flattened, leathery, and tapered at both ends, the soldier fly larva drifts just beneath the surface film of ponds and marshes, filtering algae and organic debris while breathing through a fringe of water-repellent hairs at its tail.
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Phantom Midge Larva
Almost invisible in open water, the phantom midge larva is a slender, transparent predator that drifts through the water column, using a pair of internal gas-filled sacs to hover at precise depths while hunting tiny prey.
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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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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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Diving Beetle Larva (Water Tiger)
Nicknamed the water tiger, the larva of a predaceous diving beetle is an elongated, sickle-jawed hunter that stalks the shallows and seizes prey many times its own size.
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Milkweed Bug (Large Milkweed Bug)
A boldly patterned orange-and-black true bug found clustering on milkweed seed pods, sporting an elongated body with a distinctive black band across the wings.
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Brown Marmorated Stink Bug
An invasive, mottled brown stink bug identified by alternating light and dark bands on its antennae and abdomen edges, well known for gathering in large numbers on and inside buildings each fall.
true-bug
Field Cricket
A stout, dark cricket whose loud, rhythmic chirping is one of the most familiar summer and fall night sounds in fields and lawns across much of the world.
grasshopper-cricket
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.
caterpillar-larva
Caddisfly
A moth-like insect whose larvae are famous for constructing portable protective cases out of silk and whatever sand, twigs, or debris they can find.
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