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.

Flesh Fly
A bristly gray fly marked with three dark thoracic stripes and a checkerboard-patterned abdomen, often spotted hovering near carrion or garbage.
fly
Maggot
A pale, legless, tapering grub that wriggles through rotting food and organic waste, the larval stage of a fly.
caterpillar-larva
Root Maggot
A small, legless white grub that lives hidden in the soil, tunneling into the roots of cabbage-family vegetables where it feeds unseen.
fly
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.
aquatic-insect
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.
aquatic-insect
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.
aquatic-insect
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.
aquatic-insect
Rat-Tailed Maggot
Named for its long, thin, telescoping breathing tube, the rat-tailed maggot is the aquatic larva of the drone fly, thriving in stagnant, low-oxygen water where few other insects can survive.
aquatic-insect
Caddisfly Larva
A soft-bodied aquatic larva famous for building a portable protective case from sand, gravel, or plant debris bound together with silk.
aquatic-insect
Onion Fly
A slender gray fly closely related to houseflies whose white legless larvae bore into onion bulbs, feeding in clusters within a single rotting bulb.
fly
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
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
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.
aquatic-insect
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.
caterpillar-larva
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.
aquatic-insect
Mosquito Larva
A wriggling, comma-shaped aquatic larva that hangs from the water's surface to breathe before transforming into a flying adult mosquito.
aquatic-insect
Fruit Fly (Vinegar Fly)
A tiny tan fly with bright red eyes that seems to appear from nowhere the moment a piece of fruit begins to overripen or a splash of wine is left uncovered.
fly
Horse Fly
A stout, fast-flying fly with large iridescent eyes and a heavy, robust body, known for its persistent, buzzing pursuit of large mammals on warm summer days.
fly
Blow Fly
A brilliant, metallic green fly that gleams like a jewel in sunlight, quickly locating decaying material with an acute sense of smell.
fly
Deer Fly
A small but aggressive fly with strikingly patterned, dark-banded wings and bright green or gold eyes, often circling the head and shoulders while hunting for a blood meal.
fly
Stable Fly
A gray fly that looks almost identical to the common house fly, but carries a rigid, forward-pointing proboscis built for piercing skin rather than sponging up liquids.
fly
Drain Fly
A tiny, fuzzy gray-tan fly with broad, moth-like wings held tent-fashion over its body, often seen resting motionless on bathroom walls near drains.
fly
Sand Fly
A tiny, densely hairy fly that holds its wings erect in a distinctive V-shape and travels in short, silent hops rather than sustained flight.
fly
Phorid Fly
A tiny, hump-backed fly best known for scuttling erratically across countertops and floors rather than taking flight, drawn to anything rotting or moist.
fly