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.

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.
caterpillar-larvaSpiny 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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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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Bristly Rose Slug
Despite its caterpillar-like, slug-shaped body covered in fine bristles, this pale green larva is actually the offspring of a small sawfly and feeds on rose leaves by skeletonizing them from the underside.
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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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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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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.
mothSlug
A soft-bodied, shell-less land mollusk that glides on a muscular foot, leaving a silvery mucus trail as it forages across damp ground and vegetation.
otherCaterpillar
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.
caterpillar-larvaTent Caterpillar
A social, blue-striped caterpillar that builds a conspicuous silken tent in the fork of a tree branch, sheltering large colonies of siblings that emerge together to feed on leaves.
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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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Buck Moth Caterpillar
A dark, spiny caterpillar covered in branched spines that marches across oak-lined sidewalks in dense groups each spring.
caterpillar-larvaTussock 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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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.
caterpillar-larvaForest 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.
caterpillar-larvaCecropia 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.
caterpillar-larvaMonarch 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.
caterpillar-larvaMourning 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.
caterpillar-larvaQuestion 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
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.
caterpillar-larvaPolyphemus 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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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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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.
caterpillar-larvaCabbage 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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