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.

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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Slug

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.

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Hag Moth Caterpillar (Monkey Slug)

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

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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Chinese Oak Silkmoth

Chinese Oak Silkmoth

A large, rust-brown silkmoth with prominent transparent eyespots on all four wings, native to oak forests of China and long cultivated there for coarse tussah silk production.

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Spiny Flower Mantis

Spiny Flower Mantis

A small, boldly patterned mantis whose wing markings resemble a pair of eyespots, flashed open in a startling display whenever a predator ventures too close.

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Spiny Orb Weaver

Spiny Orb Weaver

A small, hard-shelled orb weaver shaped like a tiny crab, with six sharp spines projecting from a brightly colored abdomen suspended in a neat wheel-shaped web.

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Caterpillar

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.

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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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Tent 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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Saddleback Caterpillar

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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Puss Caterpillar

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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Monarch 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.

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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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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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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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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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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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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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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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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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