Flies
Common pest species found in New York:
House Fly
Musca domestica

Size: 1/4 inch long (6–7 mm); about the width of a pencil eraser
Color: Dull gray and black with red eyes
Shape: Small, oval-shaped body with large eyes, 6 legs, and 1 pair of wings
Legs: 6 legs; often seen rubbing the front two together for cleaning
Antennae: Tiny antennae that are barely visible to the naked eye
Head: Large, red compound eyes that cover most of its head
Body: Look for 4 dark, longitudinal bands on the thorax (running from its head to the base of its wings); abdomen has striped or checkered markings with a yellowish underside
Wings: One pair of membranous wings; slightly yellow near the body
Fruit Fly
Drosophila melanogaster

Size: 1/8 inch long (3–4 mm); about the thickness of a phone charging cable
Color: Tan or brownish-yellow with red eyes
Shape: Small, oval-shaped body with large eyes, 6 legs, and 1 pair of wings
Legs: 6 legs; often seen rubbing the front two together for cleaning
Antennae: Tiny antennae that are barely visible to the naked eye
Head: Large compound eyes that are most often bright red (but can sometimes be dark-colored)
Body: Look for transverse black stripes across the rear portion of its abdomen
Wings: One pair of membranous wings; transparent and colorless
Drain Flies / Moth Flies
Multiple species (Psychoda spp.)

Size: Some species are as small as 1/16 inch (1.5 mm) while others are as big as 1/5 inch long (5 mm)
Color: Light tan to dark grayish-brown with a mottled appearance
Shape: Small, hairy, moth-shaped body with furry antennae, 6 legs, and 1 pair of wings
Legs: 6 legs; brown with white rings at the tips
Antennae: Furry-looking antennae with 13 segments; about the same length as its abdomen; covered in long white hairs
Body: Covered entirely with a dense coat of fine hairs
Wings: Broad, oval-shaped wings covered in grayish-brown hairs; look for white spots at the edges
Phorid Flies
Multiple species (Phoridae spp.)

Size: Some species are as small as 1/64 inch (0.5 mm) while others are as big as 1/4 inch (6 mm)
Color: Brown, black, or yellow
Shape: Small, hump-backed body with a small head, 6 legs, and 1 pair of wings
Legs: 6 legs; back legs are noticeably longer; sometimes called as “scuttle flies” because they like to run and hop in jerky, erratic manner
Antennae: Tiny antennae that are barely visible to the naked eye
Head: Small, bristly head tucked under its thorax; large, black compound eyes
Body: Look for a strongly arched thorax that gives it a pronounced hump-back appearance when viewed from the side
Wings: One pair of membranous wings; transparent and colorless
Biting Midges / No-See-Ums
Multiple species (Culicoides spp.)

Size: 1/25–1/8 inch long (1–3 mm); smaller than the thickness of a phone charging cable
Color: Gray or black
Shape: Small, oval-shaped body with a tiny head, thin antennae, 6 legs, and 1 pair of wings
Legs: 6 legs
Antennae: Thin antennae with 15 segments; about half the length of its body
Head: Tiny head with large, compound eyes; long mandibles and sharp teeth for biting; females suck blood but males do not
Body: Relatively large abdomen that’s tapered at the end; turns red and swollen after sucking blood
Wings: One pair of clear or grayish-colored wings with patterns of light and dark markings (difficult to see with the naked eye due to their size)
Fungus Gnats
Multiple species (Sciaridae, Diadocidiidae, Ditomyiidae, Keroplatidae, Bolitophilidae, and Mycetophilidae spp.)

Size: 1/16–1/8 inch long (1.5–3 mm); smaller than the thickness of a phone charging cable
Color: Most are gray or black; some species are yellow, orange, or brown
Shape: Tiny, mosquito-like body with a long, slender abdomen, thread-like antennae, 6 long legs, and 1 pair of wings
Legs: 6 legs that are long and slender
Antennae: Long, thread-like antennae
Head: Small head with moderately prominent compound eyes
Body: Thin, delicate-looking body with a long, slender abdomen; resembles a tiny mosquito
Wings: One pair of membranous wings; color ranges from clear to smoky gray