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.

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
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
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
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
Wolf Spiderling
A tiny, fast-moving juvenile wolf spider, often seen riding in dozens on its mother's back before dispersing to hunt on its own across open ground.
spider
Cottonwood Borer
A large, boldly patterned longhorn beetle in black and chalky white checkerboard markings, often found clinging to the trunks of cottonwood and poplar trees near its larvae's root tunnels.
beetle
Zebra Longwing
A slow-flying, long-winged black butterfly striped boldly with yellow, unusual among butterflies for feeding on pollen as an adult, which extends its lifespan to several months.
butterfly
Familiar Bluet
One of the most widespread and abundant damselflies in North America, the Familiar Bluet's slender sky-blue and black body is a near-constant sight over ponds and lakes in warm months.
other
March Fly
A stout, all-black fly that emerges in sudden, dense swarms during the first warm days of spring, often dangling its long hind legs conspicuously in slow, low flight over grass. Its name comes from its habit of appearing reliably around the start of the month, sometimes on cue near a particular saint's feast day in the traditional European calendar.
fly