Alphabetical List of Critters
(A) (B) (C) (D) (E) (F) (G) (H) (I) (J) (K) (L) (M) (N) (O) (P) (R) (S) (T) (V) (W) (Y)
- Acrobat Ant
- Allegheny Mound Ant
- Ambush Bugs
- American Carrion Beetle
- American Cockroach
- American Dagger Caterpillar (see Caterpillars)
- American Dog Tick
- American Lady / American Painted Lady (very similar to a Painted Lady) (BugGuide.net)
- American Serpentine Leafminer (University of Florida)
- Annual Cicada
- Ants
- Aphids
- Apple Maggot
- Armyworms
- Ash Bark Beetles
- Asian Longhorned Beetle (invasive) (no confirmed sightings in Maine as yet)
- Asiatic Garden Beetle
- Asparagus Beetles (Common and Spotted)
- Assassin Bugs
- Aster Leafhopper
- Azalea Lace Bug
- Azalea Leafminer
- Backswimmers (UWM)
- Bald-faced Hornets
- Banded Sexton Beetle (BugGuide.net)
- Banded Tussock Caterpillar
- Banded Woollybear (BugGuide.net)
- Bark Beetles
- Barklice (and Booklice)
- Bat Bugs (Michigan State University)
- Bean Leaf Beetle
- Bed Bugs
- Bedstraw Sphinx (Galium Sphinx) Caterpillar
- Bees — some online resources available include:
- Understanding Native Bees, the Great Pollinators: Enhancing Their Habitat in Maine (UMaine Extension)
- How to Create a Bee-Friendly Landscape (UMaine Extension)
- “Bee Health“ by eXtension! (a National Cooperative Extension resource)
- Solitary Ground-nesting Bees (Penn State)
- Beetle Grubs
- Bella Moth / Beautiful Utetheisa
- Bird Mites (UMN Extension)
- Bird Tick
- Black-legged Tick/Deer Tick
- Black and Yellow Garden Spider (Penn State) – see also Ohio DNR
- Black Blister Beetle
- Black Carpet Beetle
- Black Swallowtail / Eastern Black Swallowtail (University of Florida) | Caterpillar (photo) and Butterfly (photo)
- Black Flies
- Black Vine Weevil
- Blister Beetles
- Blood-colored Checkered Beetle (Beneficial) (BugGuide.net)
- Blow Flies and Flesh Flies
- Blueberry Insect Pests (specific to Maine low-bush blueberry):
- Blueberry Flea Beetle
- Blueberry Maggot
- Blueberry Spanworm
- Blueberry Thrips
- Red-striped Fireworm
- Spotted-wing Drosophila (see Fruit Flies)
- Booklice (and Barklice)
- Bot Flies (BugGuide.net)
- Mouse Bot Fly Cuterebra fontinella (BugGuide.net)
- Rabbit Bot Fly Cuterebra buccata (BugGuide.net)
- Bot fly larvae and pupae (BugGuide.net)
- Boxelder Bugs (BugGuide.net) See also: Boxelder Bugs (Univ. of Minnesota Extension)
- Broadhorned Flour Beetle
- Broad-nosed Weevils (BugGuide.net)
- Broad Mites (Tennessee State Univ.)
- Bronze Carabid / Bronze Ground Beetle
- Brown-banded Cockroach
- Brown-hooded Owlet Caterpillar
- Brown Prionid (Beetle) (BugGuide.net)
- Browntail Moth/Caterpillar
- Brown Dog Tick
- Brown Marmorated Stink Bug
- Bumblebees (BugGuide.net) — see also How to Create a Bee-Friendly Landscape
- Butterflies and Moths
- Butterflies (The Butterflies and Moths of North America project)
- Cabbage Looper
- Cabbage Maggot
- Cabbageworm/Imported Cabbageworm
- Caddisflies (BugGuide.net)
- Camel Crickets
- Candy-striped Leafhopper
- Carpenter Ants
- Carpenter Bees (University of Kentucky)
- Carpet Beetles
- Carrion Beetles
- American Burying Beetle (Nicrophorus americanus) (endangered) (BugGuide.net)
- American Carrion Beetle (Necrophila americana)
- Banded Sexton Beetle (Nicrophorus investigator) (BugGuide.net)
- Boreal Burying Beetle (Nicrophorus vespilloides) (BugGuide.net)
- Margined Carrion Beetle (Oiceoptoma noveboracense)
- Roundneck Sexton Beetle (Nicrophorus orbicollis) (BugGuide.net)
- Tomentose Burying Beetle (Nicrophorus tomentosus) (BugGuide.net)
- Caterpillars
- Cecropia Moth
- Cellar Spiders
- Centipedes
- Charadra deridens caterpillar
- Chinch Bugs
- Cicadas
- Clavate Tortoise Beetle
- Clay-colored Weevil
- Click Beetles
- Clothes Moths
- Clouded Sulphur butterfly (BugGuide.net)
- Clover Mites (Penn State)
- Cluster Flies
- Cockroaches
- Codling Moth
- Coffin Flies (one common species indoors is Megaselia scalaris) (BugGuide.net)
- Collembola: Springtails / Snowfleas
- Colorado Potato Beetle
- Common Asparagus Beetle
- Common Ringlet (BugGuide.net)
- Common Stalk Borer
- Confused Flour Beetle
- Corn Earworm
- Corn Rootworm (Northern, Western & Southern)
- Cornfield Ant
- Crab Spiders (BugGuide.net) (Family: Thomisdae)
- Cranberry Insect Pests:
- Blackheaded Fireworm
- Cranberry Fruitworm (cranberry and highbush blueberry pest)
- Cranberry Weevil
- Cranberry Tipworm
- False Armyworm
- Redheaded Flea Beetle
- Crane Flies
- Crazy Ant
- Crickets
- Cucumber Beetle (Striped Cucumber Beetle)
- Curve-toothed Geometer (BugGuide.net)
- Cutworms
- Cyclamen Mites (Univ. of Kentucky)
- Damselflies
- Dark Fishing Spider
- Dark Paper Wasp / Golden Paper Wasp / Northern Paper Wasp (BugGuide.net)
- Dark-winged Fungus Gnats (See Fungus Gnats)
- Deer Flies
- Deer Tick
- Diamondback Moth
- Diamondback Soil Centipede
- Dobsonflies
- Dogwood Sawfly (Iowa State Univ. Extension) (additional images, including the adult stage: BugGuide.net)
- Dog Tick
- Dragonflies
- Drain Flies (also called Moth Flies)
- Drone Fly/Dronefly
- Drugstore Beetles (Univ. of Florida) | See also Drugstore Beetle (BugGuide.net) and Drugstore Beetles (Univ. of Wisconsin)
- Dusky [wood] Cockroach – Ectobius lapponicus (BugGuide.net)
- Dust Mites
- Earwigs
- Eastern Ash Bark Beetle
- Eastern Black Swallowtail (University of Florida) | Caterpillar (photo) and Butterfly (photo)
- Eastern Boxelder Bugs (BugGuide.net) See also: Boxelder Bugs (Univ. of Minnesota Extension)
- Eastern Cicada-killer Wasp (Sphecius speciosus) (Missouri Dept. of Conservation) See also: Eastern Cicada-killer Wasp (BugGuide.net)
- Eastern Hemlock Looper
- Eastern Parson Spider (Penn State)
- Eastern Subterranean Termites (PDF) (Cornell University) — Rare in Maine; mostly occur only in pocket areas in some southern and coastal locations.
- Eastern Tent Caterpillars
- Elm Sawfly
- Emerald Ash Borer (invasive)
- Euonymus Caterpillars
- European Apple Sawfly
- European Chafer
- European Corn Borer
- European Crane Fly (invasive)
- European Ground Beetle
- European Hornet
- European Pine Sawfly
- European Red Ant / European Fire Ant (invasive)
- European Red Mite
- Eyed Click Beetle (Eyed Elater)
- Fall Armyworm
- Fall Webworm
- False Black Widow Spider (Penn State)
- False Honey Ant
- Field Crickets
- Filmy Dome Spider
- Firebrats (and Silverfish)
- Fireflies (BugGuide.net)
- Fishflies
- Fishing Spiders
- Flat Bark Beetle (Penn State / New Kensington) (Maine specimen/photo)
- Flea Beetles
- Fleas
- Flesh Flies and Blow Flies
- Flour Beetles
- Flour / Grain Mites (University of Kentucky)
- Flour Moth
- Flower Flies (also called Hover Flies or Syrphid Flies)
- Forest Pests (Maine Forest Service)
- Forest Tent Caterpillars
- Four-lined Plant Bug (BugGuide.net)
- Four-lined Silverfish
- Foxglove Aphids
- Fruit Flies
- Fuller Rose Beetle (weevil) (Univ. of Florida)
- Fungus Gnats
- Fungus Moths
- Galium Sphinx Moth (BugGuide.net)
- Galium Sphinx caterpillar (photo courtesy of Ellen Lamb)
- Galium Sphinx caterpillar (staff photo)
- Galium Sphinx pupa (staff photo)
- Garden Spider (Penn State) see also Ohio DNR
- Garden Tiger Moth (Butterflies and Moths of North America Project)
- German Cockroach
- Giant Water Bug
- Golden Ground Beetle (metallic green but with gold reflections) (BugGuide.net)
- Golden Paper Wasp / Northern Paper Wasp (BugGuide.net)
- Goldenrod Crab Spider (BugGuide.net)
- Grain Beetles
- Grain / Flour Mites (University of Kentucky)
- Granary, Rice, and Maize Weevils
- Great Golden Digger Wasp (University of Wisconsin)
- Great Tiger Moth (Butterflies and Moths of North America Project)
- Green Peach Aphids
- Ground Beetles (some examples):
- Bronze Carabid / Bronze Ground Beetle
- Golden Ground Beetle (metallic green but with gold reflections) (BugGuide.net)
- Ground and Tiger Beetles (Penn State)
- Groundhog (Woodchuck) Tick
- Ground-nesting Solitary Bees (Penn State)
- Grubs (White Grubs)
- G**** Moth — find it now by its new name of Spongy Moth
- Half-Wing (geometer moth)
- Half-Wing moth (staff photo)
- Half-Wing (BugGuide.net)
- Head Lice
- Hemlock Looper
- Hemlock Woolly Adelgid (invasive)
- Hermit Flower Beetle (BugGuide.net)
- Hickory Tussock Caterpillar
- Honey bees (eXtension.org)
- Hornets/Wasps/Yellowjackets
- Horntails (Family Siricidae)
- Hornworms
- Horse Flies
- Horsehair Worm
- House Centipede
- House Crickets (most often in basements)
- House Dust Mites
- House Flies
- Hover Flies (also called Flower Flies or Syrphid Flies)
- Hummingbird Clearwing Moth (BugGuide.net)
- Humpbacked Flies (one common species indoors is Megaselia scalaris) (BugGuide.net)
- Ichneumonid wasps (Texas A&M)
- Imported Cabbageworm
- Inchworms (Loopers/Geometers) (USGS) | See also Caterpillars of Eastern Forests (PDF) (pp 69-85) (US Forest Service)
- Indian Meal Moth
- Introduced Pine Sawfly
- Japanese Beetles — includes a video: How to Get Rid of Japanese Beetles
- Jumping Spiders (University of Arizona)
- Jumping Worms (Maine’s Department of ACF would like to emphasize that this worm is relatively widespread at this point–13 counties as of August 2023–so please do not panic if you believe or know that you have some on your property.)
- Jumping/Snake (Amynthas) Worms in Maine (Maine Dept of ACF)
- Frequently Asked Questions (UMass Extension)
- If you believe you’ve found a Jumping Worm in Maine: (link recently corrected) Jumping Worm(s) Report Form (Maine Dept of ACF)
- June Beetles
- Katydids (also known as long-horned grasshoppers)
- Kennel Tick
- Lace Bugs
- Lacewings (Virginia Tech)
- Ladybugs / Ladybird Beetles
- Larder Beetles
- Large Yellow Underwing (Oregon State Univ)
- Larger Yellow Ants
- Laugher caterpillar
- Leafhoppers – see also:
- Aster Leafhopper
- Candy-striped Leafhopper
- Potato Leafhopper (part of UMaine Extension’s Potato IPM Program)
- Leafminers
- Birch Leafminers (University of Minnesota)
- Leafminers in Home Gardens (University of Minnesota)
- Leafminers of Vegetable Crops (Utah State University)
- Serpentine (American Serpentine) Leafminer (University of Florida)
- Vegetable Leafminer (University of Florida)
- Leatherjackets (Crane fly larvae)
- Leek Moth (invasive) (University of Vermont)
- Leopard Slugs
- Lesser Grain Borers
- Lesser Mealworms
- Lice / Booklice
- Lice / Head Lice
- Lily Leaf Beetle
- Little Black Ant
- Locust Borer
- Lone Star Tick
- Longhorned Beetles (and Roundheaded Borers) (Iowa State Univ.) — see also listing for Asian Longhorned Beetle
- Loopers (USGS) | See also Caterpillars of Eastern Forests (PDF) (pp 69-85) (US Forest Service)
- Lovebugs (Family Bibionidae) (BugGuide.net)
- Luna Moth (and caterpillar)
- Lymantria dispar (Spongy Moth)
- Maize, Rice, and Granary Weevils
- March Flies (BugGuide.net) | Helpful fact sheet: March Flies (NC State Extension)
- Margined Carrion Beetle
- Masked Hunter
- Mason and Potter Wasps (Solitary wasps that are capable of stinging but they are rarely aggressive) Genus Ancistrocerus (BugGuide.net)
- May/June Beetles
- Mayflies (Michigan State Univ. Extension)
- Meal Moth (BugGuide.net)
- Mealworms
- Mealybugs
- Merchant Grain Beetle
- Metallic Wood-Boring Beetle (Univ. of Minnesota Extension)
- Mexican Bean Beetle
- Microcaddisflies (BugGuide.net)
- Milkweed Tussock Caterpillar (The Butterflies and Moths of North America project)
- Millipedes
- Mites
- Bird Mites [will bite people in the absence of their bird host(s)] (University of Minnesota Extension)
- Clover Mites (Penn State)
- Dust Mites / House Dust Mites
- Mold Mites / Tyroglyphid Mites (Iowa State University)
- Grain / Flour Mites (University of Kentucky)
- Spider Mites
- Straw Itch Mites (Oklahoma State Dept of Health)
- Parasitic Mites of Humans (University of Kentucky)
- Monarch Butterfly and Caterpillar
- Moose Tick
- Mosquitoes (Maine Forest Service) see also:
- Mosquito Species Occurring in Maine (Maine Forest Service) | Curious about the risk of malaria in Maine? Maine CDC addresses this question.
- Mosquito Biology (UMaine Extension)
- Mosquito Management (UMaine Extension)
- Insect Repellents (UMaine Extension)
- West Nile Virus (CDC)
- Preventing Eastern Equine Encephalitis (EEE) Virus in Maine
- Moth Flies (also called Drain Flies)
- Moths (and Butterflies)
- Mourning Cloak Butterfly (The Butterflies and Moths of North America project)
- Mouse Tick
- Mullein Plant Bug (Cornell)
- Multicolored Asian Lady Beetle
- Non-biting Midges (NS State Extension)
- Northeastern Pine Sawyer Beetle
- Northern Corn Rootworm (includes Western & Southern also) (Univ. of Illinois)
- Northern Paper Wasp / Golden Paper Wasp (BugGuide.net)
- Northern Pearly-eye Butterfly (BugGuide.net)
- Nursery Web Spider
- Oblique-banded Leafroller (Cornell)
- Odorous House Ants (Tapinoma sessile):
- Odorous House Ant (Penn State)
- Odorous House Ants (University of Minnesota Extension)
- Oil Beetles
- One-eyed Sphinx Moth (BugGuide.net)
- Onion Maggots
- Onion Thrips (Cornell)
- Orbweaver spiders (visit our Spiders page)
- Oriental Beetle (NC State Extension)
- Painted Lady (Butterflies and Moths of North America Project)
- Pantry pests:
- Paper Wasps/Yellowjackets/Hornets
- Parson Spider
- Parthenice Tiger Moth
- Pavement Ants
- Pennsylvania Wood Roach
- Pharaoh Ant (Univ. of Minnesota Extension)
- Phorid Flies (one common species indoors is Megaselia scalaris) (BugGuide.net)
- Picnic Beetles (Univ. of Minnesota Extension)
- Pillbugs (Univ. of Maryland / UMD Cooperative Extension)
- Pine Needle Scale (US Forest Service)
- Plant Diseases
- Plum Curculio (Cornell)
- Polyphemus Moth (Butterflies and Moths of North America Project)
- Pond Skaters (Water Striders)
- Potato Pests (UMaine Extension’s Potato Pest Control Guide)
- Aphids (Green Peach Aphids and Potato Aphids)
- Armyworms
- Cabbage Looper
- Clavate Tortoise Beetles
- Colorado Potato Beetle
- Cutworms
- European Corn Borer
- Flea Beetles
- Leafhoppers
- Leafminers
- Leafminers in Home Gardens (University of Minnesota)
- Leafminers of Vegetable Crops (Utah State University)
- Vegetable Leafminer (University of Florida)
- Potato (and other) Aphids (part of UMaine Extension’s Potato IPM Program)
- Potato Leafhopper (part of UMaine Extension’s Potato IPM Program)
- Tarnished Plant Bug
- Three-lined Potato Beetle [pdf] (UNH) (uncommon on potato and less damaging than the Colorado Potato Beetle)
- Tortoise Beetles
- Wireworms
- Yellowstriped Armyworm (Univ. of Florida)
- Potter and Mason Wasps (Solitary wasps that are capable of stinging but they are rarely aggressive) Genus Ancistrocerus (BugGuide.net)
- Powderpost Beetles
- Praying Mantids (Univ. of Kentucky)
- Predaceous Diving Beetles (BugGuide.net)
- Predatory Stink Bugs (Univ. of Maryland)
- Pseudoscorpions (BugGuide.net)
- Rabbit Tick
- Raspberry Insect Pests:
- Raspberry Cane Borer (PDF) (Univ. of New Hampshire Cooperative Extension)
- Raspberry Cane Maggot (PDF) (Univ. of New Hampshire Cooperative Extension)
- Raspberry Crown Borer (Univ. of New Hampshire Cooperative Extension)
- Raspberry Fruitworm (Univ. of Minnesota Extension) | Photo of Raspberry Fruitworm Adult (Beetle) (scroll to bottom of page once there) (Univ. of New Hampshire Cooperative Extension)
- Red-necked Cane Borer (NC State Extension)
- Raspberry Weevil
- Spotted-wing Drosophila (see Fruit Flies)
- Red Admiral (butterfly) (BugGuide.net)
- Red-banded Leafhopper
- Red-banded Leafroller (Cornell)
- Red-headed Ash Borer (BugGuide.net)
- Redheaded Flea Beetle (part of UMaine Extension’s Cranberry IPM Program)
- Red-headed Pine Sawfly (BugGuide.net)
- Red-humped Caterpillars (UMass)
- Red-necked Cane Borer (NC State Extension)
- Red-shouldered Pine Borer (BugGuide.net)
- Red Flat Bark Beetle (Penn State / New Kensington) (Maine specimen/photo)
- Red Flour Beetle
- Rhododendron Pests:
- Azalea Leafminer
- Black Vine Weevil and Raspberry Weevil (both weevil species feed during the night)
- Lace Bugs
- Mealybugs (NC State Extension)
- Rhododendron Leafhopper (BugGuide.net)
- Rhododendron Whiteflies (Dialeurodes chittendenl) (UMass)
- Rice, Granary, and Maize Weevils
- Roaches / Cockroaches
- Robber Flies (NC State Extension)
- Rose Chafer
- Rose Leafhopper (Univ. of Washington)
- Rose Sawflies (three foliage-feeding species) (Univ. of Minnesota Extension)
- Roundheaded Apple Tree Borer (Cornell)
- Rove Beetles (University of Wisconsin-Madison)
- San Jose Scale (Cornell)
- Sap Beetles (Univ. of Minnesota Extension)
- Sand Wasps (Missouri Dept of Conservation)
- Sawflies | See also: Sawflies (Univ. of Wisconsin Extension) | Sawflies (UMN Extension)
- Birch Sawfly (BugGuide.net)
- Elm Sawfly
- Dogwood Sawfly (Iowa State Univ Extension) (additional images, including the adult stage: BugGuide.net)
- Dusky Birch Sawfly (BugGuide.net)
- European Apple Sawfly
- European Pine Sawfly
- Horntails (Family Siricidae)
- Introduced Pine Sawfly
- Red-headed Pine Sawfly (BugGuide.net)
- Sphacophilus cellularis (hosts: plants in the Convolvulaceae family; bindweed/morning glory)
- Striped Alder Sawfly (hosts include red alder, paper birch and willow)
- Tenthredo grandis (feeds on turtleheads/Chelone) (BugGuide.net)
- White Pine Sawfly
- Yellow-headed Spruce Sawfly (BugGuide.net)
- Sawtoothed Grain Beetles
- Sawyer Beetles
- Scarab Beetles (see also White Grubs)
- Examples
- Asiatic Garden Beetles
- European Chafers
- Hermit Flower Beetles (BugGuide.net)
- Japanese Beetles
- May/June Beetles
- Oriental Beetles (NC State Extension)
- Rose Chafers
- Examples
- Scorpionflies (Univ. of Kentucky)
- Scuttle Flies (one common species indoors is Megaselia scalaris) (BugGuide.net)
- Seabird Tick
- Seedcorn Maggot (Univ. of Minnesota Extension) | see also Delia platura (BugGuide.net)
- Silverfish (and Firebrats)
- Six-spotted Tiger Beetle (BugGuide.net)
- Slug Caterpillars (BugGuide.net)
- Slugs
- Small-headed Fly
- Snails
- Snowfleas
- Sod Webworm (Penn State)
- Solitary Ground-nesting Bees (Penn State)
- Southern Corn Rootworm (includes Western & Northern) (University of Illinois)
- Southern Pine Beetle (Dendroctonus frontalis) (invasive) — Detected in Waterboro, Maine in October, 2021 (Maine Forest Service) | Some Photos of the Southern Pine Beetle (BugGuide.net)
- Sowbugs (Univ. of Maryland / UMD Cooperative Extension)
- Spider Beetles (people sometimes mistake these for spiders, bed bugs, or ticks)
- Spiders
- Spider Mites
- Spongy Moth
- Spotted Asparagus Beetle
- Spotted Lanternfly (planthopper) (find it on our Invasive Species page)
- Spotted Tentiform Leafminer (Cornell)
- Spotted Tussock Caterpillar
- Spotted Wing Drosophila (invasive) (see Fruit Flies)
- Springtails / Snowfleas
- Spruce Budworm
- Squash Beetles / Squash Lady Beetles
- Squash Bugs
- Squash Vine Borer (University of Minnesota) (larva photo) (adult photo)
- Squirrel Tick
- Stable Fly (University of Florida)
- Stalk Borer / Common Stalk Borer
- Stink Bugs
- Stoneflies (BugGuide.net)
- Straw Itch Mites (Oklahoma State Dept of Health)
- Strawberry Clipper Weevil (also called Strawberry Bud Weevil) (Anthonomous signatus Say) (Cornell)
- Strawberry Root Weevil (Otiorhynchus ovatus)
- Strawberry Root Weevil (Oregon State University Extension)
- Home-invading Weevils (University of Minnesota Extension)
- Strawberry Rootworm
- Strawberry Seed Beetle
- Striped Cucumber Beetle
- Sugar Maple Borer (BugGuide.net)
- Sweat Bees (BugGuide.net)
- Syrphid Flies (also called Hover Flies or Flower Flies)
- Tachinid Flies (University of Wisconsin)
- Tachinid Fly (Hystricia abrupta) (BugGuide.net)
- Tachinid Fly (Juriniopsis adusta) (BugGuide.net)
- Tachinid Fly (genus Cylindromyia) (BugGuide.net)
- Tanbark Borer / Violet Tanbark Beetle (BugGuide.net)
- Tarnished Plant Bug
- Tawny Garden Slug
- Tent Caterpillars: Eastern Tent Caterpillars and Forest Tent Caterpillars
- Termites (NC State Extension) — Rare in Maine; mostly occur only in pocket areas in some southern and coastal locations.
- ‘The Laugher’ caterpillar
- Thief Ant (University of Minnesota Extension)
- Thread-waisted wasps (Family Sphecidae):
- Gold-marked Thread-waisted Wasp (BugGuide.net)
- Great Golden Digger Wasp (Univ. of Wisconsin)
- Three-lined Potato Beetle [pdf] (UNH)
- Thrips (vectors of tospoviruses including Tomato Spotted Wilt Virus and Impatiens Necrotic Spot Virus)
- Ticks
- Tiger Beetles (Texas A&M)
- Tiger Beetles of Vermont (iNaturalist)
- Maine IF&W: Rare Tiger Beetles
- Ground and Tiger Beetles (Penn State)
- Six-spotted Tiger Beetle (BugGuide.net)
- Tobacco Hornworm
- Toe-Biter (also called Giant Water Bug)
- Tomato Hornworm
- Tomentose Burying Beetle (BugGuide.net)
- Tortoise Beetles
- Tussock Caterpillars
- Two-Spotted Spider Mites
- Varied Carpet Beetle
- Vegetable Leafminer (University of Florida)
- Velvet Ants (look on our “Ants” page for these, even though they are actually wasps)
- Viburnum Leaf Beetle
- Viburnum Leaf Beetle Fact Sheet (pdf) (Cornell Cooperative Extension)
- Viburnum Leaf Beetle Fact Sheet (UMass Extension)
- Viburnum Leaf Beetle (Oregon State University) (good photos)
- What is eating the leaves of my viburnum? (Univ. of New Hampshire Extension)
- Violet Tanbark Beetle (from oak firewood) (BugGuide.net)
- Virginia Ctenucha (Butterflies and Moths of North America project)
- Virginian Tiger Moth (often mistaken in Maine for the Browntail Moth) (BugGuide.net)
- Wasps/Hornets/Yellowjackets
- Water Boatmen (UWM)
- Water Scavenger Beetles (Texas A&M)
- Waterscorpions
- Water Striders
- West Nile Virus (CDC)
- Western Conifer Seed Bug
- Western Corn Rootworm (includes Northern and Southern also) (University of Illinois)
- Whiteflies (University of Missouri)
- Whitespotted Sawyer Beetle
- White Apple Leafhopper (Univ. of Washington)
- White Grubs
- White Pine Sawfly
- White Pine Weevil
- Winter Cutworm – Noctua pronuba (Oregon State Univ)
- Winter Firefly
- Winter Moth (Maine Forest Service) | Banding trees [pdf] to capture the moths or caterpillars (helpful instructions from the Town of Harpswell) [see also Control of Winter Moth Damage in New England Blueberries (PDF) — UMass] [2012 Bangor Daily winter moth story] and the Maine Forest Service Press Release (Nov-Dec 2015) “When moths fly with snow, let the Maine Forest Service know!”
- Winter Tick
- Wireworms
- Woodchuck Tick
- Woodlice / Sowbugs (Univ. of Maryland / UMD Cooperative Extension)
- Wood Tick/American Dog Tick
- Wood Roaches
- Woollybear Caterpillars (BugGuide.net): Banded Woollybear and Yellow Woollybear
- Yellowjackets/Hornets/Wasps
- Yellownecked Caterpillars (Penn State University)
- Yellow-striped Armyworm (BugGuide.net) [see also Yellowstriped Armyworm (Univ. of Florida)]
- Yellow Woollybear (BugGuide.net)