45 insects containing the letter O — each with origin, classification, and notes.
Below are insects that contain the letter O anywhere in the name. Each of the 45 insects below opens to a full profile.
A metallic blue-green fly whose larvae (maggots) are the primary decomposers of carrion — ecologically vital as recyclers of dead matter, useful in forensic entomology, and controversial as both medical tool and livestock pest.
The sulphur-yellow butterfly that heralds spring — males are an unmistakable lemon-yellow, females a paler greenish-white; one of the longest-lived British butterflies, spending the winter as an adult hibernating among ivy and evergreen leaves, then emerging on warm February days to become the first butterfly many people see each year.
One of Britain's most extraordinary camouflaged insects — at rest, the buff-tip moth is almost indistinguishable from a broken birch twig, with its pale yellow-buff wing tips and grey middle aligned to mimic a stub of birch; the hairy, yellow-and-black larvae are gregarious and can strip a tree of leaves in days.
A brilliantly coloured day-flying moth of chalk downland and coastal grassland — the six-spot burnet has six vivid red spots on metallic blue-black forewings, a warning colouration that advertises its toxicity; burnet moths produce hydrogen cyanide from their own tissues as a chemical defence, making them poisonous to predators; conspicuous in sunshine on downland flowers, flying weakly but apparently without concern for predators.
Moths with transparent wings that convincingly mimic wasps and bees — the hornet moth looks exactly like a hornet; other species mimic bumblebees or wasps so precisely that even experienced naturalists hesitate; adults are active by day and fly fast; larvae bore in tree trunks, stems, and roots for 2–3 years.
A large, fast, exceptionally hardy insect that has been on Earth for 200+ million years and is now a near-universal urban pest, the species behind most "cockroach" stories.
The world's most destructive potato pest — a striped yellow-and-black beetle native to the Rocky Mountains that spread across North America and then Europe by the early 20th century, capable of stripping entire potato fields bare; Britain has so far kept it out through strict biosecurity controls.
A ragged-winged butterfly of woodland edges and hedgerows — named for the small white comma-shaped mark on the underside of its hindwing; the scalloped, jagged wing outline gives roosting adults a dead-leaf appearance of startling realism; common in England and Wales, the comma has expanded its range northward in recent decades.
The soil-dwelling caterpillar larvae of noctuid moths — one of the most destructive garden and agricultural pests, cutting seedlings off at soil level overnight, yet the adult moths are harmless and often beautiful.
A common name applied to several different long-legged arachnids — including harvestmen (which aren't spiders), cellar spiders, and crane flies (an actual insect) — none of which are dangerous to humans despite persistent myths.
A large, prehistoric-looking aquatic insect with enormous sickle-shaped jaws (in males) whose larvae spend up to three years in clean streams before emerging for a brief, non-feeding adult life of 3–7 days.
A large, fast-flying dragonfly that migrates thousands of kilometers across North America in a multi-generational journey, an ancient predator with extraordinary aerial agility.
Britain's only day-flying member of the silk moth family — the male emperor moth is one of the most spectacular insects on British heathland, with large owl-like eyespots on all four wings; the male can detect a female's pheromone from up to 11 km away; the caterpillar is a vivid green and black jewel, and the silk cocoon was once harvested.
The world's greatest jumper relative to body size — the common froghopper can jump 70 cm straight up, accelerating at 400 g, which is greater than the force experienced by a fighter pilot in a dogfight; the larvae are hidden inside "cuckoo spit" — the white froth seen on plant stems each spring.
A bioluminescent insect larva (or wingless adult female of certain beetles) that produces a steady greenish glow to attract prey or mates — including the New Zealand cave-dwelling species that creates one of the world's most spectacular natural light displays.
The heaviest insect on Earth — a male goliath beetle in its larval stage can weigh up to 100 grams, more than a small bird; the adults are strikingly patterned in black and white and can reach 110 mm in length; found in the tropical rainforests of Africa, they are popular in the insect-keeping hobby.
A jumping insect with powerful hind legs and short antennae, eaten across many human cultures and capable, in certain species, of transforming into devastating swarming locusts.
A large, fast-moving, predatory beetle that hunts at night — one of the gardener's best allies, consuming slugs, aphids, and other pests by the thousand, and a key component of healthy soil ecosystems.
The largest moths in the world — powerful fliers with streamlined wings, capable of hovering in front of flowers like hummingbirds while feeding with enormously long tongues; the deaths-head hawk-moth has a skull-pattern on its thorax and squeaks when disturbed.
A flying social insect that pollinates roughly a third of human food crops and produces honey from the nectar of flowers.
A large social wasp with a particularly painful sting — including the European hornet that builds paper nests in tree hollows and the notorious Asian giant hornet, the "murder hornet" that decimates honeybee colonies.
A large biting fly with painful blood-feeding females — capable of cutting through skin with scissor-like mouthparts, leaving wounds that bleed freely and persist for hours, with major impacts on livestock and outdoor activities.
The master mimics of the insect world — hoverflies are entirely harmless flies that mimic the yellow-and-black warning patterns of bees and wasps with remarkable accuracy; they hover motionless mid-air and visit flowers as important pollinators; the larvae include important aphid predators and the bizarre "rat-tailed maggot" that breathes through a snorkel tube while living in polluted water.
The caterpillar of geometer moths, distinguished by its looping "measure-the-cloth" gait — pulling rear feet up to front feet, then arching forward — and famous in nursery songs.
A grasshopper that has transformed into the swarming phase — physiologically distinct from its solitary form, capable of forming billion-strong swarms that devastate agriculture across continents.
Beetles whose antennae are often longer than their entire body — the larvae bore through wood for years before emerging as adults; some of the most destructive tree pests in the world, while others are important wood-decay specialists in old-growth forests.
A wingless parasitic insect — head lice are particularly common among schoolchildren, body lice can transmit serious diseases including epidemic typhus, and pubic lice are a sexually transmitted parasite.
A small, blood-feeding fly responsible for more human deaths annually than any other animal, the primary vector for malaria, dengue, yellow fever, and Zika.
A large, pale-green silk moth of eastern North America with long curved hindwing tails — adults that don't eat at all, living only a week to mate and die.
A tiny biting midge so small it slips through standard window screens, leaving disproportionately painful itchy welts — the bane of summer evenings in coastal and wetland areas.
A strange, flightless beetle with a swollen, soft abdomen and a fascinating life history — females lay thousands of eggs, the tiny larvae (triungulins) climb flowers and hitch a ride on mining bees back to their burrows, where they feed on the bee's pollen stores and develop through multiple larval stages; when threatened, the beetles exude a blistering oil (cantharidin) from their leg joints.
A delicate white butterfly of spring hedgerows — males have vivid orange wingtips that give the species its name, while females are white with black tips, easily mistaken for other whites; the underside of both sexes is marbled green and white, providing perfect camouflage on cow parsley flowers where they roost.
A dragonfly-like insect with massive owl-like compound eyes and clubbed antennae, related to lacewings, that hunts mosquitoes and small flying insects on the wing at dusk.
A large, furry, pale grey moth whose caterpillar is one of the most extraordinary in Britain — vivid green with a dark saddle, a fierce face-like pattern, and two whip-like tails that it waves when threatened; adults are beautifully marked with grey and cream patterning and are among the most striking moths of woodland edges and riverside willows.
The small, light-brown cockroach species responsible for nearly all kitchen-pest cockroach infestations worldwide — fast-breeding, hard to eliminate, and the bane of restaurants and apartment buildings.
The apex predators of the insect world — powerfully built flies that hunt other insects on the wing, seizing prey mid-air with spiny legs and injecting a paralysing venom, then sucking the prey dry; they tackle prey larger than themselves including wasps, bees, and dragonflies.
A large family of beetles with characteristically short wing covers that expose most of the abdomen — the most species-rich beetle family, playing crucial roles as predators, scavengers, and even ant-colony infiltrators.
An ancient arachnid with venomous tail and pincered front claws — among the oldest land animals on Earth (430 million years), with surprising longevity and bizarre fluorescence under UV light.
A bizarre-looking woodland insect named for the male's upturned, scorpion-like tail — actually the genitalia, not a sting; scorpionflies have a long, beak-like rostrum, mottled brown and yellow wings, and a peculiar habit of stealing prey from spider webs; they are significant scavengers of dead insects and small animals, and are among the oldest winged insect lineages.
A soft-bodied, colourful beetle named for its scarlet-and-black colour reminiscent of a British redcoat soldier — an important pollinator that visits flowers for pollen while hunting smaller insects.
An ancient aquatic insect whose larvae are the gold standard of clean water — stonefly larvae require highly oxygenated, cold, unpolluted streams to survive, making them invaluable biological indicators of water quality; adults are drab, flat-winged insects that rest on bankside stones and vegetation, rarely flying far from the stream where they developed; one of the most ancient insect orders, with fossils over 300 million years old.
Small, bell-shaped moths whose caterpillars are among the most damaging to gardens and orchards — they roll leaves into shelters bound with silk and eat the enclosed tissue; the codling moth (apple's worst enemy) and the light brown apple moth are tortrix moths, and European vine moth damages grapevines worldwide.
A large nocturnal moth with cryptic gray-brown forewings camouflaged like tree bark, concealing brilliantly colored hindwings flashed in startle displays to confuse predators.
A small white moth bound to yucca plants in an obligate mutualism — the only insect that pollinates yucca, while yucca seeds are the only food its larvae can eat.
A tiny, obscure insect in the small order Zoraptera — sometimes called "angel insects" — known mostly to specialists, with a strange dimorphism and a phylogenetic position that has long puzzled entomologists.
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