Of the 39 species found in our database, the following are established in Pennsylvania. Our current understanding of each spider's distribution is drawn from numerous scientific publications and online spider submissions in order to be as accurate as possible. It is important to remember that spiders are not bound by the territorial lines decided on by humans, therefore their distribution is subject to change. Occasionally, spiders can be found well outside of their known range due to being intentionally or accidentally transported by humans in cars, luggage, and other belongings.
Species Found in Pennsylvania
“Grass Spiders” are represented by 13 species collectively found throughout most of the U.S. and southern Canada, and northern Mexico. Like all members of the funnel weaver family Agelenidae, they spin dense, non-sticky, sheet-like webs with a funnel-like retreat where the spider hides.
Native to Europe, it has become established in southeastern Canada and the eastern U.S., though is not limited to those regions. This robust spider is common in and around homes, but also lives under rocks, logs, in leaf litter, and other dark, humid places. Adult males are notorious for wandering in the spring.
This spider is named for the pattern of white spots on the abdomen that form a cross in most specimens. Native to Europe, it was introduced to North America long ago. It spins the classic wheel-like orb web, usually sitting head-down in the hub (center), at night as well as during the day.
Mature females are enormous, their bold black-and-yellow pattern adding to their intimidating appearance. Common in gardens, orchards, forest edges, old fields, and farms, they spin a classic round orb web which is usually decorated with a bold, zigzag band of silk called a stabilimentum.
Females are large, silvery spiders with legs banded in black and yellow. Look for this species in late summer and fall in fields, prairies, gardens, and meadows. The circular webs are built close to the ground amid tall grasses and weeds, often with a zigzag band of silk running through the center.
This strikingly patterned species is a wandering hunter, often catching prey at night as well as during the day. They live close to the ground, under rocks and logs or in leaf litter, but are also occasionally found on (or in) buildings. Their movements are often ant-like, earning them the nickname “antmimic.”
“Longlegged Sac Spiders” are pale green, tan, or yellow nocturnal hunting spiders with very long front legs. Native to southern Europe, this spider has made its way into North America, where it is now fairly widespread. It is commonly found indoors, where it prowls walls and ceilings at night, looking for prey or mates.
These very large, sprawling arachnids are most often found on vertical surfaces: tree trunks, fence posts, bridge pilings, or the exterior walls of buildings, usually at night. There, they wait in ambush for large insects to come within striking distance. They do not spin webs to catch prey, but simply overpower their victims.
A large and strong hunting spider, this species is more closely associated with water than any of the other Nearctic fishing spiders. Find it among aquatic vegetation at the margins of streams and rivers, as well as floating around in lakes and residential pools. It eats aquatic insects, small fish, or even small amphibians!
Native to Europe, and now widespread across the globe, this brightly colored spider is hard to miss. The long jaws and fangs are used to stab or turn over its prey: land isopods like sowbugs and roly-polies. This species does not spin a web, but hunts “on foot,” sometimes straying indoors.
This a hunting spider that does not spin a web to capture prey. It gets its common name from the black and white color pattern reminiscent of the garb worn by old-time clergymen. Common east of the Rocky Mountains, it sometimes strays indoors in the course of prowling for a meal or seeking a mate.
This species is the largest “wolf spider” in North America. Females reach 22-35 millimeters in body length. Their legspan is greater still. This spider may hunt actively at night, or wait in ambush at the mouth of its burrow, where it hides during the day. Adult males may wander indoors during mating season.
Mature females are black with a red hourglass on the belly, easily visible as the spider hangs upside down in its web at night. By day, they hide. Immature females have pale stripes and spots, gradually losing those markings as they age. These are shy spiders, and if you avoid placing your hands where you can’t see, bites are unlikely.
“Orchard Orbweavers” are brilliantly colored spiders with shimmering silver-white, green, and gold on their abdomens. The orb-shaped web is nearly horizontal and the spider hangs underneath it. It is a common and widespread species in eastern North America, as well as parts of California and Arizona.
The “Arrowshaped Micrathena” is a unique little orbweaver found in the eastern U.S. west to Nebraska and Texas. The shape and coloration of the female make it easily identifiable. The orb web of this species is usually built in low bushes in open deciduous woodlands and along forest edges.
This spider is an ambush hunter, lying patiently in wait on flowers for an insect to come within striking range. Adult females may be overall yellow or white, with the ability to change back and forth. This species can conquer surprisingly large prey like bees and butterflies.
This spider waits in ambush on flowers for visiting insects to come within range, seizing a victim in the embrace of its first two pairs of legs. Adult females can change from white to yellow and vice versa, though the change takes some time. Males are very small and strikingly different than females.
This species is relatively variable in color and sometimes pattern, but is most commonly seen sporting a rusty-red or golden orange color. The orb-shaped web is very large and is often constructed on buildings and other man-made structures, especially near outdoor lights. This species is most conspicuous in late summer and early fall.
This species is abundant and widespread across the entire world, and is closely associated with buildings and other man-made structures. The teardrop-shaped, papery brown egg sacs can aid in their identification. The spider’s color and body shape cause them to be mistaken for “brown widows” on occasion.
This is a relatively large, bright green spider with long, spiny legs and lightning fast movements. They are typically spotted in shrubs and bushes during the day, where they are sit-and-wait predators. Incredibly, this spider is capable of “spitting” venom in self-defense.
The “Bold Jumper” is one of the largest and most common species of jumping spider in North America. The spider is mostly black with a conspicuous white, orange, or red triangular patch in the center of its abdomen. Take a close look at this spider’s chelicerae (jaws), as they have a gorgeous, iridescent sheen to them and come in a variety of colors!
The Longbodied Cellar Spider is thought to be native to Europe, but can be found globally after having traveled nearly everywhere as a stowaway in commerce. Their long, thin legs and elongated abdomen make them relatively easy to identify. Find them on ceilings, in basements, storage sheds, old wells, caves, and other dry locations with low light.
This is a large hunting spider that comes in a variety of color forms, sometimes making them more difficult to identify. It is a commonly seen species throughout the eastern United States and southeastern Canada. Females construct a nursery web and suspend their egg sac in it, guarding the babies that emerge.
These jumping spiders are frequently seen patrolling the outer walls of buildings and other vertical surfaces, looking for bugs to pounce on. The mottled gray, black, and white scalloped pattern on their abdomen makes them one of the easier spiders to identify in the field.
The zebra-like color pattern makes this species one of the easier jumping spiders to identify in the field. It is most common around urban and suburban areas where it hunts by day on fences, rock walls, the exterior of buildings, and similar situations. Thought to be native to Europe, it is also now established in the U.S., southern Canada, and Asia.
This ornately-marked spider immobilizes its prey by spitting a mixture of silk, glue, and venom onto it. Watch for this slow-moving species leisurely walking the walls and ceilings at night. They are easily recognized by their dome-shaped carapace and thin, banded legs.
The “False Black Widow” belongs to the same family as true black widows, and is easily mistaken for its dangerous cousins. However, note that this spider does not have the red hourglass on the underside of the abdomen. It is common in buildings, but may live outdoors in sheltered spots such as wood piles, under bridges, or in rock walls.
Today, this species occurs nearly everywhere people live, having spread with international commerce. The sheet-like webs of this spider are conspicuous in dark corners of barns, cellars, sheds, garages, cabins, and other man-made structures. Adult males frequently get caught in bathtubs or sinks at night.
This species is a wandering hunter that may be encountered indoors on occasion and is often referred to as the “Broadfaced Sac Spider.” Normally lives in leaf litter, under bark, or in curled leaves, where it hides by day and emerges at night to prowl for insects. Often confused with the “Woodlouse Hunter,” but lacks the long jaws of that species.