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.

Spined Soldier Bug
A predatory stink bug identified by the sharp, pointed spines projecting from its shoulders, valued in gardens and farm fields for hunting caterpillars, beetle larvae, and other pest insects.
true-bug
Metallic Wood-boring Beetle
The North American common name for jewel beetles, emphasizing the wood-tunneling habits of their larvae, which leave telltale flattened, D-shaped exit holes in bark of stressed or dying trees.
beetle
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.
caterpillar-larva
Rootworm
Working unseen below ground, rootworm larvae chew tunnels through the root systems of corn and other crops, the underground counterpart to the small, often striped or spotted beetles seen on leaves and flowers above.
beetle
Pine Sawyer Beetle
A large, long-antennaed longhorn beetle of pine and spruce forests, mottled gray-brown to black, that produces a rasping sound when handled and whose larvae tunnel deep into dead or dying conifer wood.
beetle
Bess Beetle
A large, glossy jet-black beetle that lives in family groups inside rotting logs, communicating with fellow beetles through squeaks and cooperating to raise larvae, an unusually social lifestyle for an insect of its kind.
beetle
Mediterranean Flour Moth
A small, pale grey moth with fine dark wavy lines on its forewings, whose larvae spin webbing through flour, grain, and other stored dry food products, making it a well-known pest of mills and pantries.
moth
Ailanthus Silkmoth (Cynthia Moth)
A very large silkmoth with broad, tan-brown wings crossed by white, crescent-moon-shaped bands, closely associated with the fast-spreading tree-of-heaven that both feeds its larvae and carried the species around the world.
moth
Isabella Tiger Moth (Woolly Bear)
Famous chiefly in its larval stage as the banded woolly bear caterpillar, this tiger moth's fuzzy black-and-rust-colored caterpillar is a familiar autumn sight, while the adult is a soft, tawny-orange moth with a stout, furry body.
moth
Pine Processionary Moth
An unremarkable grey-brown moth known almost entirely through its larvae, which build large silken nests in pine trees and travel to feed in long, head-to-tail processions covered in fine defensive hairs.
moth
Cellar Spider
A pale, long-legged spider that builds loose, irregular webs in dark corners and is famous for rapidly vibrating in its web when disturbed, causing it to blur into an indistinct shape.
spider
Rosy Apple Aphid
A small, dusty pink to purplish-gray aphid that clusters on apple foliage in spring, causing distinctive curled, reddened leaves that make its presence easy to spot even before the insects themselves are seen.
true-bug
Bogong Moth
A modest brown, mottled moth famous for its extraordinary mass seasonal migration across thousands of kilometers to cool alpine caves in the Australian mountains, forming one of the largest known insect migrations by biomass.
moth
Bot Fly
A stocky, bumblebee-mimicking fly whose adults never feed and live only long enough to mate and locate a rodent or rabbit burrow for their eggs. Despite their harmless, buzzing adult stage, bot flies are best known through the larvae that develop as internal parasites of small mammals.
fly
Pillbug
A gray, armor-plated land crustacean that curls into a tight ball at the slightest touch, earning it the playful nickname "roly-poly."
other
Marsh Fly
A slender, unassuming fly best known for larvae with a remarkable diet: nearly every species in the family feeds on aquatic or terrestrial snails and slugs, making marsh flies natural specialists in wetland food webs. Adults are often found resting quietly on sedges and other marsh vegetation near the water's edge.
fly
Screwworm Fly
A metallic blue-green blowfly whose larvae are unusual among maggots for feeding on living tissue rather than carrion, drawn to even small open wounds on warm-blooded animals. The species has been the target of one of the most successful large-scale insect eradication campaigns in history across much of North America.
fly
Long-Legged Fly
A jewel-bright little fly that flashes metallic green, blue, or bronze in the sunlight as it darts across leaves on comically long, stilt-like legs, pausing to perform quick territorial displays. Both adults and larvae are active hunters of even smaller insects, making this tiny fly a useful predator in gardens and wetlands alike.
fly
Pill Bug
A gray, segmented, armor-plated crustacean that curls into a tight ball when disturbed, commonly found under rocks, logs, and damp garden debris.
other
Tachinid Fly
A bristly, house-fly-like insect that looks unremarkable at a glance but hides one of the most important ecological roles among flies: its larvae develop as internal parasites of caterpillars, beetles, and other insects, quietly regulating populations across the landscape. Gardeners often welcome tachinid flies as natural allies against crop-damaging pests.
fly
Flat-backed Millipede
A slow, armor-plated decomposer whose body segments flare into flat, wing-like keels, giving it a distinctly ribbed, tank-like silhouette compared to rounder millipedes.
myriapod
Tick
A small, flattened, oval arachnid with a hard shield-like plate on its back that waits on vegetation and attaches to passing hosts to feed on blood, swelling considerably once fed.
arachnid
Sowbug
A slate-gray, oval, armor-plated crustacean that shuffles through damp leaf litter on seven pairs of legs, recognizable by its overlapping segmented shell and pair of trailing tail-like appendages.
other
Goliath Birdeater
The heaviest spider in the world, the Goliath birdeater is a massive, hairy tarantula from the South American rainforest whose leg span can rival a dinner plate, though despite its name it primarily hunts insects and other invertebrates rather than birds.
spider