Occasional Invader / role
18 entr(ies)
Boxelder Bug
A black-and-red true bug that feeds on female boxelder trees in summer and gathers on and inside warm buildings in fall, making it a harmless cool-season nuisance pest.Brown Marmorated Stink Bug
A shield-shaped, mottled-brown invasive stink bug from East Asia that crowds into homes in fall to overwinter and releases a foul odor when disturbed, but does not bite, breed indoors, or damage the structure.Brown Recluse
A shy, venomous brown spider of the south-central United States, known for six eyes in three pairs and a violin-shaped mark, whose bite can occasionally cause a slow-healing skin wound.Camel Cricket
A wingless, humpbacked cricket with long legs and antennae that lives in cool, damp, dark places like caves and crawl spaces, wandering into basements and garages when it seeks shelter and moisture.Clover Mite
A tiny reddish-brown plant-feeding mite, recognized by an extra-long front pair of legs, that lives on lawns and ornamentals and pours into buildings in large numbers during spring and cool spells, harmless but prone to leaving red stains when crushed.Cluster Fly
A sluggish, slightly oversized relative of the house fly whose larvae are parasites of earthworms outdoors, and whose adults pile into attics and wall voids of homes in fall to wait out the winter.Common Pillbug
A small, gray, land-dwelling crustacean that rolls into a tight ball when disturbed, lives in damp soil and leaf litter, and feeds harmlessly on decaying plant material.European Earwig
A reddish-brown, nocturnal insect best known for the pincer-like forceps at the tip of its abdomen; it shelters in damp, dark spots by day and sometimes wanders into homes in large numbers.Fruit Fly
A tiny tan-to-brown fly with red eyes that breeds in overripe, fermenting, or damaged fruit and the moist residue in drains, found around kitchen counters and trash.House Centipede
A fast, long-legged centipede with a dirty-yellow striped body that lives in damp, dark corners of homes and hunts insects and spiders at night; alarming to look at but harmless, and actually a beneficial predator.House Cricket
A light yellowish-brown cricket with three dark bands across its head that lives outdoors in warm weather and moves into buildings when it turns cool, best known for the male's chirping and for being raised as fishing bait and pet food.Millipede
A slow, worm-like, many-legged arthropod that lives in damp soil and leaf litter eating decaying plant matter, and wanders indoors by mistake when the ground outside turns too wet or too dry.Smokybrown Cockroach
A large, uniformly dark mahogany-brown peridomestic cockroach of the warm southern U.S. that breeds outdoors in mulch, woodpiles, and tree holes and flies indoors, especially into attics, on warm humid evenings.Springtail
A tiny, wingless soil arthropod, smaller than a grain of rice, that jumps with a spring-loaded fork under its body and shows up indoors in damp spots like bathrooms, basements, and overwatered houseplants.Striped Bark Scorpion
A slender, yellowish-tan scorpion marked with two broad dark stripes down the back and a dark triangle on the head, common across the south-central U.S., that climbs well and often turns up in attics and living areas of homes.Western Black Widow
A shiny black, web-bound spider of the western United States, the female marked underneath with a red hourglass; medically significant but timid, living low to the ground in dark, undisturbed clutter around buildings.Wolf Spider
A large, hairy, ground-dwelling hunting spider that chases down prey on foot instead of spinning a web, sheltering under boards, stones, and siding and sometimes wandering indoors near ground level.Yellow Sac Spider
A small, pale yellow-to-cream spider that hunts at night and rests by day in a silken tube tucked into wall and ceiling corners or outdoor cover, and that bites defensively when accidentally pressed against skin.
A black-and-red true bug that feeds on female boxelder trees in summer and gathers on and inside warm buildings in fall, making it a harmless cool-season nuisance pest.Brown Marmorated Stink Bug
A shield-shaped, mottled-brown invasive stink bug from East Asia that crowds into homes in fall to overwinter and releases a foul odor when disturbed, but does not bite, breed indoors, or damage the structure.Brown Recluse
A shy, venomous brown spider of the south-central United States, known for six eyes in three pairs and a violin-shaped mark, whose bite can occasionally cause a slow-healing skin wound.Camel Cricket
A wingless, humpbacked cricket with long legs and antennae that lives in cool, damp, dark places like caves and crawl spaces, wandering into basements and garages when it seeks shelter and moisture.Clover Mite
A tiny reddish-brown plant-feeding mite, recognized by an extra-long front pair of legs, that lives on lawns and ornamentals and pours into buildings in large numbers during spring and cool spells, harmless but prone to leaving red stains when crushed.Cluster Fly
A sluggish, slightly oversized relative of the house fly whose larvae are parasites of earthworms outdoors, and whose adults pile into attics and wall voids of homes in fall to wait out the winter.Common Pillbug
A small, gray, land-dwelling crustacean that rolls into a tight ball when disturbed, lives in damp soil and leaf litter, and feeds harmlessly on decaying plant material.European Earwig
A reddish-brown, nocturnal insect best known for the pincer-like forceps at the tip of its abdomen; it shelters in damp, dark spots by day and sometimes wanders into homes in large numbers.Fruit Fly
A tiny tan-to-brown fly with red eyes that breeds in overripe, fermenting, or damaged fruit and the moist residue in drains, found around kitchen counters and trash.House Centipede
A fast, long-legged centipede with a dirty-yellow striped body that lives in damp, dark corners of homes and hunts insects and spiders at night; alarming to look at but harmless, and actually a beneficial predator.House Cricket
A light yellowish-brown cricket with three dark bands across its head that lives outdoors in warm weather and moves into buildings when it turns cool, best known for the male's chirping and for being raised as fishing bait and pet food.Millipede
A slow, worm-like, many-legged arthropod that lives in damp soil and leaf litter eating decaying plant matter, and wanders indoors by mistake when the ground outside turns too wet or too dry.Smokybrown Cockroach
A large, uniformly dark mahogany-brown peridomestic cockroach of the warm southern U.S. that breeds outdoors in mulch, woodpiles, and tree holes and flies indoors, especially into attics, on warm humid evenings.Springtail
A tiny, wingless soil arthropod, smaller than a grain of rice, that jumps with a spring-loaded fork under its body and shows up indoors in damp spots like bathrooms, basements, and overwatered houseplants.Striped Bark Scorpion
A slender, yellowish-tan scorpion marked with two broad dark stripes down the back and a dark triangle on the head, common across the south-central U.S., that climbs well and often turns up in attics and living areas of homes.Western Black Widow
A shiny black, web-bound spider of the western United States, the female marked underneath with a red hourglass; medically significant but timid, living low to the ground in dark, undisturbed clutter around buildings.Wolf Spider
A large, hairy, ground-dwelling hunting spider that chases down prey on foot instead of spinning a web, sheltering under boards, stones, and siding and sometimes wandering indoors near ground level.Yellow Sac Spider
A small, pale yellow-to-cream spider that hunts at night and rests by day in a silken tube tucked into wall and ceiling corners or outdoor cover, and that bites defensively when accidentally pressed against skin.