Centruroides sculpturatus
Look for Slender pincers and a long, thin tail. Color runs from pale to dark, sometimes striped.
Lives Block walls, cracks, bark and wall voids. Climbs walls and crosses ceilings.
Watch for Glows under UV light at night, often several together. The only U.S. scorpion of medical concern.
Hadrurus arizonensis
Look for Heavy body and thick pincers; dark back with pale sides and legs.
Lives Low, sandy ground in the Mojave and Sonoran deserts.
Watch for The largest U.S. scorpion, but its venom is mild. It even eats bark scorpions.
Vaejovis confusus
Look for Slim, delicate pincers and a wider, bulkier tail.
Lives Sandy soil under rocks and other objects, in short burrows or scrapes.
Watch for A mild sting that usually doesn’t need medical care.
Latrodectus hesperus
Look for Shiny black with a round abdomen and a red hourglass underneath, sometimes faint or missing.
Lives Low, dark, undisturbed spots: foundations, rock piles, meter and irrigation boxes, garage doors and vents.
Watch for A messy, very strong web near the ground and yellowish teardrop egg sacs. Bites are rare but need medical care.
Loxosceles deserta
Look for Six eyes in three pairs, a plain abdomen with fine hairs, and a violin mark that’s faint or missing.
Lives Native to the Mojave and Sonoran deserts. Hides in cracks under rocks and debris, sometimes indoors.
Watch for Its venom is considered as potent as the brown recluse’s. Bites are rare.
Family Lycosidae
Look for Hairy and gray-brown to gray-black, with large forward-facing eyes. Builds no web.
Lives Mulch, rock and wood piles, and under objects around the yard.
Watch for Females carry an egg sac, then their young on their backs. Bites only if handled.
Blattella germanica
Look for Light brown with two dark stripes on the shield behind the head.
Lives Kitchens and bathrooms: warm, dark gaps near food and water.
Watch for Each egg case holds about 30 young. Droppings and shed skins can trigger asthma.
Blatta lateralis
Look for Males tan with full wings and cream edges; females dark with short, cream-edged wing pads.
Lives Water meter and irrigation boxes, block-wall cracks, compost, leaf litter and sewers.
Watch for Wanders in for water but can’t survive or breed indoors. Replacing the oriental roach in Southwest cities.
Periplaneta americana
Look for Reddish brown, with a pale band around the shield behind the head.
Lives Sewers, storm drains and water meter boxes: warm, humid spots, usually above 82°F.
Watch for Brown egg cases about 3/8 inch long that turn black, glued in hidden corners. Can carry germs onto food.
Blatta orientalis
Look for Shiny and almost black. It doesn’t fly; the males’ wings stop short.
Lives Garages, water meter boxes and drains: cool, dark, damp places.
Watch for Losing ground to the Turkestan roach, whose females have cream wing edges this one lacks.
Solenopsis xyloni
Look for Mixed sizes in one nest. Red head and thorax with a dark abdomen, or all dark.
Lives Native to Southern Nevada’s hot desert: bare, sunny soil near water and under stones.
Watch for Bites to hold on, then stings again and again. Comes indoors for crumbs, pet food and spills.
Pogonomyrmex spp.
Look for Black, brown or red. Nests in a bare, cleared circle of soil up to 12 feet across.
Lives Yards, empty lots and desert landscaping. They gather seeds and don’t invade homes.
Watch for Stings feel like a bee sting, so take care if you’re allergic. Swarms gather on roofs.
Tapinoma sessile
Look for Dark brown to black. Smells rotten, like coconut, when crushed.
Lives Mulch and under rocks or slabs; indoors near insulation or damp wood.
Watch for Many queens and linked nests make it slow to clear. Baits work but take days to weeks.
Tetramorium immigrans
Look for Small and dark brown, trailing from cracks along slabs, patios and driveways.
Lives Pavement cracks and edges, mulch beds, and under rocks or concrete.
Watch for One queen per nest, so it’s easier to control than the odorous house ant.
Solenopsis invicta
Look for Reddish-brown ants, darker on the abdomen, that pour out and sting when a mound is disturbed.
Lives Not established here. Nevada has found and destroyed colonies that came in on plants.
Watch for Stings hurt more than native fire ants’. Report suspect mounds to the Nevada Department of Agriculture.
Rattus rattus
Look for Slim and dark, with big ears and a tail longer than its body.
Lives Palms, thick shrubs, attics and wall voids. Gets in from trees and along power lines.
Watch for In the valley since 1990. Gnawed fruit, droppings, greasy rub marks and scratching overhead.
Mus musculus
Look for Gray-brown, with large ears, small black eyes and a nearly hairless tail.
Lives Slips under a 1/4-inch gap and nests in shredded paper in sheltered spots.
Watch for Droppings, gnawing, and up to 10 litters a year. Can carry salmonella and leptospirosis.
Peromyscus spp.
Look for Brown above with a white belly and feet, big eyes, and a furred tail that’s dark on top.
Lives Sheds, garages, trailers and cabins, especially ones closed up for the winter.
Watch for Carries hantavirus; infected mice were found near Cold Creek in Clark County. Never sweep or vacuum its droppings.
Culex quinquefasciatus
Look for Plain brown, with narrow pale bands across the abdomen.
Lives Dirty standing water: green pools, catch basins, old tires and bird baths.
Watch for The most common mosquito in Southern Nevada traps. It carried West Nile virus here in 2023.
Aedes aegypti
Look for Dark, with white lyre-shaped markings and white-banded legs.
Lives Lays eggs just above the waterline in pots, saucers, buckets, tires and gutters.
Watch for First trapped in Clark County in 2017 and in 43 ZIP codes by 2023. Tip out standing water weekly.
Gryllodes sigillatus
Look for Light yellowish brown or tan, with darker bands and spots.
Lives Gathers at foundations and doors. The one cricket that can live and breed indoors.
Watch for Droppings, and in large numbers it chews fabric and drywall. It doesn’t bite.
Gryllus spp.
Look for Dark brown to shiny black.
Lives Yards and planting beds. Comes inside to hide but doesn’t breed indoors.
Watch for Chews wool, cotton, silk and carpet, especially stained clothes. Turning off outdoor lights at night helps.
Forficula auricularia
Look for Reddish brown. Pincers are curved on males and straight on females.
Lives Under pavers, rocks, planters and mulch in watered beds.
Watch for Ragged holes in seedlings and soft fruit. Comes in when it’s too hot or dry; pinches only if handled.
Ctenocephalides felis
Look for Reddish brown and wingless, flattened side to side.
Lives The usual flea on cats and dogs alike. Larvae live in carpet and pet bedding.
Watch for Cocooned fleas can wait months, then hatch when someone walks in. Pets can get tapeworms.
Lepisma saccharinum
Look for Shiny silver-gray and carrot-shaped, with three long tail bristles.
Lives Damp, warm rooms like laundry rooms and bathrooms. Often stuck in tubs and sinks.
Watch for Scraped, irregular holes in paper, book bindings and wallpaper, with scales nearby.
Thermobia domestica
Look for Shaped like a silverfish but mottled gray and brown.
Lives Hot, dry spots over 90°F: attics, ovens, heaters, fireplaces and hot-water pipes.
Watch for The same paper and starch damage as silverfish. Lives about 2 years.
The brown recluse’s native range runs from Nebraska and Ohio south to Texas and Georgia. The recluse of the Mojave Desert is the desert recluse, which hides in cracks under rocks and debris. Many wounds blamed on recluse bites turn out to be skin infections such as MRSA, so have a doctor look at any wound that spreads.
The Southern Nevada Health District traps mosquitoes from March to September, and most breeding happens April through October. West Nile virus turned up in local mosquitoes in 2023, mostly southern house mosquitoes, and two people in Clark County caught it. The day-biting yellow fever mosquito has spread to dozens of ZIP codes since 2017, so empty saucers, buckets and pet bowls every week.
Most are outdoor roaches living in water meter and irrigation boxes, block walls and sewers. Turkestan roaches wander in looking for water but can’t survive or breed inside. A small, light-brown roach with two dark stripes behind its head in your kitchen is a German cockroach, which breeds indoors and needs a different plan.
Open doors and windows for 30 minutes first, and don’t sweep or vacuum. Wear gloves and a well-fitted N95 mask, spray droppings and nests with a 10% bleach solution, wait 5 to 10 minutes, then wipe up with paper towels and bag them. Nevada health officials urged extra care after two hantavirus cases in 2025.
