Spiders

Spiders belong to the class Arachnida. They have eight legs, venomous fangs, and web-spinning spinnerets. Though most spiders found in homes are harmless to people, to many people their presence still causes fear and anxiety.

In New York, yellow sac spiders are the only poisonous species that poses a risk to humans. Brown recluse and black widows are sometimes reported, but these cases are extremely rare (neither species is native to New York). According to the NYS Department of Environmental Conservation, the vast majority of bites attributed to brown recluse spiders are actually from yellow sac spiders.

Common House Spider

Parasteatoda tepidariorum

Common house spiders live in close proximity to humans and are found almost exclusively in homes and buildings.

They construct densely-woven, 3-dimenional webs that appear random or tangled. Webs are usually constructed in dry, secluded areas like in the corners of walls and windows.

These spiders only bite in self-defense. Their bites are slightly painful (akin to a bee sting) but not dangerous.

(Photo: SpiderID)

Common House Spider

Size: 1/6–1/4 inch long (4–6 mm) not including legs; about the length of a highlighter tip

Color: Brown and tan

Shape: 2 body segments with a rounded abdomen and 8 long legs (1st and 4th pairs are extra long)

Legs: 8 long legs that are tan-colored with many dark stripes; its front and back legs are particularly long (more than twice the length of its body)

Eyes: 8 eyes of equal size arranged in 2 rows (bottom: 4, top: 4)

Body: 2 body segments (cephalothorax and abdomen); mottled with light and dark markings; females have a large, bulbous abdomen that’s several times larger than the head; males have a small, rounded abdomen that’s about the same size as the head

Yellow Garden Spider

Argiope aurantia

Yellow garden spiders are typically found in yards and gardens. They rarely come indoors but may build their webs on the outside of windows and other structures.

As a part of orb weaver family, their webs are large, circular, and complex. Yellow garden spiders in particular can be identified by the bold, zig-zagging lines they weave across their webs.

These spiders are not poisonous and rarely bite (only when threatened).

(Photo: Judy Gallagher)

Yellow Garden Spider

Size: Females are 3/4–1 inch long (19–28 mm); males are 1/5–3/8 inch long (5–9 mm)

Color: Yellow and black

Shape: 2 body segments with a hairy cephalothorax, an oval-shaped abdomen, and 8 long legs (3rd pair is shorter than the rest)

Legs: 8 long legs that are mostly black with a few pale yellow or orange patches; the 3rd pair of legs is half as long as the others

Eyes: 8 eyes of equal size arranged in 2 rows (bottom: 4, top: 4)

Body: 2 body segments (cephalothorax and abdomen); its head (cephalothorax) is covered in short, silvery-white hairs; look for a smooth, shiny abdomen with symmetrical yellow and black markings

Grass Spiders

Multiple species (Agelenopsis spp.)

Grass spiders live in grassy areas, but they occasionally wander indoors in search of food and warmth during the winter.

These spiders build unique, funnel-shaped webs designed to trap flying insects. Their webs consist of a flat, sheet-like section (up to 3 feet wide) with a downward-leading funnel (up to a foot or longer).

Grass spiders are shy and only bite when threatened. Their bites may be painful but are usually harmless (except in rare cases).

(Photo: Judy Gallagher)

Grass Spider

Size: 3/8–3/4 inch long (9–20 mm) not including legs; about the length of a peanut kernel

Color: Brown and yellowish-brown

Shape: 2 body segments with an oval-shaped abdomen, tail-like spinnerets, and 8 long, bristly legs

Legs: 8 bristly legs with light and dark patches

Eyes: 8 eyes of equal size arranged in 3 rows (bottom: 2, middle: 4, top: 2)

Body: 2 body segments (cephalothorax and abdomen); covered with short, bristly brown hair; cephalothorax is yellowish-brown with 2 parallel dark stripes running down the middle of its carapace; abdomen is brown with stripes and chevron patterns; look for long, tail-like spinnerets (silk-spinning organs) protruding out from its rear end

Wolf Spiders

Multiple species (Lycosidae spp.)

Wolf spiders get their name from the way they chase down and pounce on their prey (like wolves). They’re usually found outside but may occasionally wander indoors.

Wolf spiders do not spin webs.

They’re also known for lugging their eggs around in big, round, silken sacs attached behind the abdomen of female wolf spiders.

They only bite when threatened. Their bites may be painful but are usually harmless.

(Photo: Tyson Research Center)

Wolf Spider

Size: 3/8–1 3/8 inches long (10–35 mm) not including legs; about the size of a paperclip

Color: Dark brown to gray

Shape: 2 body segments with an oval-shaped abdomen and 8 long, bristly legs

Legs: 8 bristly legs with light and dark patches

Eyes: 8 eyes of unequal size arranged in 3 rows (bottom: 4, middle: 2, top: 2); the middle pair of eyes is especially large and prominent

Body: 2 body segments (cephalothorax and abdomen); covered with short, bristly brown hair; cephalothorax is grayish-brown with 2 thick, dark bands running down the middle of its carapace; abdomen has dark brown markings; during the spring and summer, may be seen carrying around a large, white egg sac attached to its abdomen

Yellow Sac Spiders

Multiple species (Cheiracanthium spp.)

Yellow sac spiders account for the majority of reported spider bites. They are the only native spider species in New York that pose a risk to humans.

Their bites are moderately poisonous, causing pain, swelling, itchiness, and (typically mild) ulcerating sores.

These spiders normally live outside, but may wander indoors during the fall and winter in search of food and warmth. They weave small, silken tubes or sacs to rest in during the day and protect their young.

(Photo: Joe Lapp)

Yellow Sac Spider

Size: 1/6–3/8 inch long (4–10 mm) not including legs; about the length of a pea

Color: Pale yellow or straw-colored

Shape: 2 body segments with an oval-shaped abdomen and 8 long legs (1st pair is extra long)

Legs: 8 legs covered in short, pale yellow hairs with dark brown tips; the 1st pair (front legs) is longer than the others

Eyes: 8 eyes of equal size arranged in 2 rows (bottom: 4, top: 4)

Body: 2 body segments (cephalothorax and abdomen); pale, straw-colored body with dark brown jaws (chelicerae) and palps; abdomen has a faint dark stripe running down the middle

Brown Recluse

Loxosceles reclusa

Brown recluse spiders are mainly found in the South and Central Midwest. They are not native to New York.

These spiders live alone and hide in dark, undisturbed places. They sometimes enter homes in search of prey, taking up residence in crevices, closets, storage boxes, and seldom-worn shoes or clothing.

They’re not aggressive and only bite when threatened. Their bites cause pain and sometimes serious skin damage, but are rarely life-threatening.

Brown Recluse

Size: 1/4–1/2 inch long (6–12 mm) not including legs; about the length of a fingernail

Color: Tan to dark brown

Shape: 2 body segments with an oval-shaped abdomen and 8 long legs

Legs: 8 long, slender legs that are uniformly brown-colored (no bands or markings)

Eyes: 6 eyes arranged in a distinctive semi-circular arrangement consisting of 3 pairs (1 pair in the middle and 2 pairs on the sides)

Body: 2 body segments (cephalothorax and abdomen); covered with short, fine hairs; cephalothorax has a dark, violin-shaped marking on the back of its carapace pointing backwards towards its abdomen (although this feature is not always apparent)