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.

White Admiral
A large, dark butterfly crossed by a bold white band on both wings, the northern form of the same species that produces the iridescent blue Red-spotted Purple farther south.
butterfly
Eastern Pondhawk
A bold, ground-perching dragonfly whose bright green females and powdery blue males look almost like different species, and which readily preys on other dragonflies.
dragonfly
Planthopper
A varied group of sap-feeding true bugs known for their sideways-held wings, jumping ability, and, in some tropical species, exaggerated head projections used for display.
true-bug
Devil's Flower Mantis
One of the largest mantis species on Earth, this striking insect can suddenly rear up and fan out vividly colored wings and legs into a dramatic, flower-like threat display.
mantis-stick
Four-spotted Skimmer
A brown, sturdily built dragonfly marked with a single dark spot on each wing, this holarctic species is famous for occasional mass emergences and long-distance swarming flights.
dragonfly
Cotton Bollworm
A variably colored caterpillar, ranging from green to brown to nearly pink, that burrows into cotton bolls, corn ears, and tomato fruit, feeding concealed inside the very structures it damages.
caterpillar-larva
Bollworm
One of the most economically significant caterpillars in North American agriculture, the bollworm changes color from green to brown to pink across its life and bores into cotton bolls, corn ears, and tomato fruit alike.
caterpillar-larva
Dobsonfly Larva (Hellgrammite)
A large, fierce-looking aquatic larva with strong pinching jaws and fringed side gills, spending years hunting under stream rocks before becoming a giant winged dobsonfly.
aquatic-insect
Corn Earworm Moth
A tan to olive-colored moth whose caterpillar, the corn earworm, is one of the most economically significant crop pests in North America, feeding inside corn ears, tomatoes, and cotton bolls.
moth
Daddy Longlegs (Harvestman)
A leggy, one-piece-bodied arachnid that scurries through leaf litter and garden beds on impossibly long, spindly legs, easily mistaken for a spider despite belonging to an entirely different arachnid order.
arachnid
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
Corn Earworm
A color-variable caterpillar, ranging from pale green to reddish-brown, that burrows headfirst into corn ears and is one of the most economically significant crop pests in North America.
caterpillar-larva
Pearl Crescent
A small, orange-and-black checkered butterfly that is one of the most abundant and widespread species in open fields across the continent, easily recognized by its crescent-shaped pale marking on the hindwing underside.
butterfly
Human Bot Fly
A stout, dark-bodied fly from the American tropics famous for an unusual reproductive trick: it captures a blood-feeding mosquito mid-flight and glues its own eggs to the mosquito's body before releasing it to carry them to a future host. The adult itself is rarely seen, spending most of its short life in shaded forest understory.
fly
Giant Water Bug
A massive, flattened oval true bug with powerful grasping front legs, the giant water bug is North America's largest aquatic insect and an ambush predator lurking just below the surface of still water.
aquatic-insect
Deer Tick
A small, dark-legged tick with a reddish-brown, teardrop-shaped body, noticeably smaller than many other common tick species and often found questing in wooded or grassy edge habitats.
arachnid
Cicada
A stout, big-eyed insect best known for the loud, buzzing chorus of song produced by males, and for periodical species that emerge from the ground by the millions after living underground for over a decade.
true-bug
Green Peach Aphid
A small, pale yellow-green aphid with an exceptionally broad host range, recognized as one of the most widespread and adaptable aphid species found on garden vegetables, ornamentals, and stone fruit trees.
true-bug
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
Fork-tailed Bush Katydid
Slimmer and greener than its treetop relatives, the fork-tailed bush katydid lives among shrubs and garden plants, with males identified by the distinctive forked appendages at the tip of the abdomen that give the species its name.
grasshopper-cricket
Viceroy Butterfly
An orange-and-black butterfly closely resembling the monarch, distinguished by a smaller size and a distinctive black line crossing the veins of the hindwing, and long cited as a classic example of mimicry between two unrelated species.
butterfly
Picture-Winged Fly
A small fly whose clear wings are decorated with bold bands, spots, or intricate patterns, often waved and flicked in slow, deliberate displays that give the impression of a tiny fan being opened and closed. Some species even raise their patterned wings above the body and walk sideways in courtship displays reminiscent of a strutting peacock.
fly
Louse Fly
A flattened, leathery-bodied fly that clamps onto fur or feathers with stout claws and scuttles sideways like a tiny crab rather than taking flight when disturbed. Several species shed their wings for good once they settle on a permanent host, spending the rest of their lives buried in fleece or plumage.
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