Idaho Pest Library

Tetramorium caespitum

Pavement ants are small, dark brown to black ants measuring 2.5-4mm. They have parallel grooved lines on their head and ...

Camponotus species

Carpenter ants are among the largest ants in North America, measuring 6-13mm. Most are solid black, though some species ...

Tapinoma sessile

Odorous house ants are small, brown to black ants that produce a distinctive "rotten coconut" smell when crushed. They'r...

Monomorium pharaonis

Pharaoh ants are extremely small (1.5-2mm), light yellow to reddish-brown ants with darker abdomens. They're almost tran...

Cimex lectularius

Bed bugs are flat, oval, reddish-brown insects about the size of an apple seed (4-7mm). After feeding, they become more ...

Blattella germanica

German cockroaches are small, light brown roaches with two distinctive dark parallel stripes running from head to wing b...

Lepisma saccharina

Silverfish are distinctive, carrot-shaped insects covered in silvery scales. They have two long antennae and three tail-...

Culicidae family

Mosquitoes are small, slender flies with long legs and a distinctive proboscis for feeding. Females are the biters—they ...

Ctenocephalides felis/canis

Fleas are tiny, wingless insects with laterally compressed bodies designed for moving through fur. They're dark reddish-...

Ixodidae family

Ticks are not insects but arachnids related to spiders. They have oval, flat bodies (when unfed) that become engorged an...

Culicoides spp.

Biting midges, commonly called no-see-ums, are tiny flying insects barely visible to the naked eye. They look like minia...

Anthrenus spp., Attagenus spp.

Adult carpet beetles are small, oval, and often have colorful mottled patterns. Common species include varied carpet bee...

Plodia interpunctella

Indian meal moths are easily identified by their distinctive wings: the inner half is creamy-white and the outer half is...

Psychodidae family

Drain flies (moth flies) are small, fuzzy flies with large, leaf-shaped wings held roof-like over their body. They look ...

Drosophila melanogaster

Fruit flies are tiny tan flies with distinctive bright red eyes. They hover around ripening fruit, vegetables, and ferme...

Musca domestica

House flies are medium-sized gray flies with four dark longitudinal stripes on the thorax. They have large reddish-brown...

Latrodectus hesperus

Female black widows are shiny jet-black with a distinctive red hourglass marking on the underside of their globular abdo...

Eratigena agrestis

Hobo spiders are medium-sized brown spiders measuring 10-14mm. They have a distinctive chevron (V-shaped) pattern on the...

Lycosidae family

Wolf spiders are large, hairy spiders ranging from 10-35mm. They're typically brown, gray, or tan with darker markings o...

Eratigena atrica

Giant house spiders are among the largest spiders in Idaho, with leg spans up to 75mm (3 inches). They're brown with mot...

Cheiracanthium species

Yellow sac spiders are small (5-10mm) pale yellow to light green spiders with slightly darker jaws. They build small sil...

Pholcus phalangioides

Cellar spiders have small tan bodies (6-9mm) with extremely long, thin legs that can span 50mm or more. They build loose...

Loxosceles reclusa

Brown recluse spiders are identified by the distinctive dark violin-shaped marking on their cephalothorax (head region),...

Mus musculus

House mice are small rodents with dusty gray to light brown fur, large ears relative to body size, and long scaly tails ...

Rattus norvegicus

Norway rats are large, robust rodents measuring 7-10 inches with tails shorter than their body length. They have brown o...

Rattus rattus

Roof rats are sleek, agile rodents with tails longer than their body length. They have dark brown to black fur, large ea...

Microtus spp.

Voles (meadow mice) are small, stocky rodents with short tails, small ears, and blunt snouts. They're often confused wit...

Scalopus aquaticus

Moles are easily identified by their large, paddle-like front feet designed for digging. They have pointed snouts, tiny ...

Thomomys spp.

Pocket gophers are medium-sized burrowing rodents with small eyes and ears, large front teeth, and external fur-lined ch...

Vespula species

Yellowjackets are black and yellow striped wasps, often confused with bees. Key differences: yellowjackets have smooth b...

Polistes species

Paper wasps are slender wasps with long legs that dangle during flight. They're typically brown with yellow markings and...

Dolichovespula maculata

Bald-faced hornets are large, black wasps with distinctive white markings on their face and abdomen tip. They build larg...

Sceliphron caementarium

Mud daubers are distinctive wasps with extremely thin, thread-like waists connecting thorax and abdomen. They can be bla...

Forficula auricularia

Earwigs are distinctive insects with elongated bodies and prominent pincers (cerci) at the rear. They're dark brown to r...

Halyomorpha halys

Brown marmorated stink bugs are shield-shaped insects, 14-17mm long, with mottled brown coloring. Key identifiers includ...

Harmonia axyridis

Asian lady beetles look similar to native ladybugs but have distinguishing features: a black "M" or "W" shape behind the...

Pollenia species

Cluster flies are slightly larger than house flies, with dark gray bodies covered in golden-yellow hairs. They move slug...

Boisea trivittata

Box elder bugs are black bugs with distinctive red or orange markings on their backs. Adults are about 12-14mm long with...

Arocatus melanocephalus

Elm seed bugs are small, oval insects with dark brown/black bodies and distinctive rust-red edges on their wings. They h...

Scutigera coleoptrata (house centipede) and others

Centipedes have flattened, segmented bodies with one pair of legs per segment. House centipedes have extremely long legs...

Diplopoda class

Millipedes have cylindrical, segmented bodies with two pairs of legs per segment (unlike centipedes' one pair). They cur...

Armadillidium vulgare (pillbug), Porcellio laevis (sowbug)

Sowbugs and pillbugs (roly-polies) are crustaceans, not insects—they're related to shrimp and crabs. Pillbugs roll into ...

Acheta domesticus (house), Gryllus spp. (field)

Crickets have cylindrical bodies, long antennae, and enlarged hind legs for jumping. House crickets are yellowish-brown ...

Collembola order

Springtails are tiny, wingless arthropods with a forked tail-like structure (furcula) that allows them to jump. They're ...

Bryobia praetiosa

Clover mites are tiny, oval mites with a characteristic reddish-brown color. Their front legs are much longer than other...