21 Types of Spiders in Maryland (With Identification Tips)
November 7, 2026
Maryland’s spider population is far more diverse than most residents realize. The Maryland Biodiversity Project tracks hundreds of species stretching from the Chesapeake Bay marshes to the Appalachian ridges in the west, yet the vast majority of them pose no threat to people at all.
Among all these types of spiders in Maryland, only one is considered medically significant, while the rest spend their time quietly catching mosquitoes, flies, and other backyard pests. Knowing the difference between a black widow and a common house spider takes the guesswork out of every web you find in the garage or garden.
This guide walks through 21 spiders you’re likely to encounter in Maryland, covering how to identify each one, where it tends to hide, and whether it deserves a second glance or simply a polite relocation outdoors. For a broader look at arachnid diversity, Maryland’s snake species and beetle populations add even more texture to the state’s wildlife, but spiders remain some of the most misunderstood residents of any Maryland backyard.
Pro Tip: Most spider bites in Maryland happen when a spider is accidentally touched or trapped against skin while someone is moving firewood, cleaning a shed, or reaching into a dark corner. Wearing gloves in cluttered outdoor storage areas prevents the large majority of incidents.
1. Black Widow
The black widow is the only spider in Maryland that homeowners genuinely need to watch for. Two native species occupy the state: the southern black widow (Latrodectus mactans) and the northern black widow (Latrodectus variolus), with an introduced brown widow (Latrodectus geometricus) also turning up occasionally.
Females are glossy, almost plastic-looking black spiders with a red hourglass marking on the underside of the abdomen, though the northern species may show broken red spots instead of a complete hourglass. The body measures roughly half an inch long, and the spider hangs upside down in a loose, irregular web.
Black widows are common throughout Maryland but are rarely found indoors, preferring wood piles, window wells, sheds, and other undisturbed outdoor clutter. Despite the reputation, they rarely bite humans and are often described as shy, typically biting only when pressed directly against skin. Anyone wanting a deeper look at which North American species carry medically significant venom can check this list of poisonous spider species for context beyond Maryland’s borders.
2. Wolf Spider
Wolf spiders are the large, fast-moving hunters that startle people when they dash across a basement floor. They belong to the family Lycosidae, and Maryland’s wolf spiders don’t build webs at all, instead relying on strong vision to actively chase down prey day and night.
One common Maryland species, Rabidosa rabida, shows the earth-toned, sometimes striped coloring typical of the group. Body length ranges from about a quarter inch to one and a half inches, with a leg span reaching roughly three inches. Females carry their egg sacs on their spinnerets and let newly hatched spiderlings ride on their backs, a behavior that sets them apart from nearly every other spider in the state.
Wolf spiders are mildly venomous, but a bite typically causes nothing worse than mild, short-lived itching. Readers curious how Maryland’s wolf spider populations compare to other states can look at this roundup of spiders found in Missouri, where ground-hunting species are equally common in rural areas.
3. Common House Spider
The common house spider, Parasteatoda tepidariorum, is the small brown spider responsible for most of the messy cobwebs tucked into basement corners and ceiling edges. It belongs to the cobweb spider family, Theridiidae, the same family that includes black widows, though it poses no medical risk to people.
This species builds a tangled, three-dimensional web and simply waits for flies, gnats, and other small insects to blunder into it. Because it rarely strays far from its web, it’s one of the easiest Maryland spiders to live alongside without ever noticing it. Urban apartments and older homes tend to host larger populations, similar to patterns seen among spiders found in Chicago buildings with comparable indoor humidity and clutter.
4. Cellar Spider
Cellar spiders, family Pholcidae, are the thin, long-legged spiders sometimes mistaken for daddy longlegs harvestmen. They are commonly found in homes but typically stay in one place and don’t bother people, spinning loose, haphazard webs in damp basements, crawl spaces, and garage corners.
The most widespread species, Pholcus phalangioides, has a small body paired with extremely delicate legs that can span several inches. When disturbed, cellar spiders vibrate rapidly in their webs rather than fleeing, a defense tactic that often blurs their outline entirely. Their proportions are a good introduction to the broader category of spiders with unusually long legs found across North America.
5. Giant Lichen Orb Weaver
The giant lichen orb weaver, Araneus bicentenarius, is one of the largest orb-weaving spiders a Maryland resident might encounter. Its mottled gray, white, and brown coloring mimics tree bark and lichen almost perfectly, which is exactly how it avoids predators while resting flat against a trunk during the day.
At night, this spider builds a large, classic wheel-shaped web to catch moths and other flying insects, often near porch lights or wooded yard edges. Despite its intimidating size, it is completely harmless to people and will typically drop from its web or play dead if handled. Orb weavers as a group make up some of the most visually striking entries among the many different types of spiders found across the eastern United States.
6. Furrow Spider
The furrow spider, Larinioides cornutus, is a medium-sized orb weaver frequently found near water, bridges, and outdoor lighting. Its abdomen shows a distinctive folium pattern of light and dark brown markings that resembles a furrowed field, which gives the species its common name.
These spiders are especially active after dusk, rebuilding their circular webs nightly to capture flying insects drawn to porch lights and streetlamps. Furrow spiders are harmless and tend to retreat into a nearby curled leaf or crevice during daylight hours rather than sitting exposed in the web. Neighboring states report similar orb-weaver activity, as seen in guides covering spiders found in Pennsylvania.
7. Woodlouse Spider
The woodlouse spider, Dysdera crocata, has a reddish-orange cephalothorax paired with a pale, almost translucent gray abdomen, giving it a two-toned look that’s easy to recognize once seen. True to its name, this species specializes in hunting woodlice (pillbugs) and uses unusually long, forward-projecting fangs to pierce their hard shells.
Woodlouse spiders are nocturnal hunters that hide under rocks, logs, mulch, and garden debris during the day. They can deliver a bite if handled roughly, but the effect is comparable to a minor bee sting and causes no lasting harm. Gardeners dealing with similar debris-dwelling hunters elsewhere might compare notes with this guide to spiders found in Ohio.
8. Heptagonal Orb Weaver
The heptagonal orb weaver is a lesser-known member of the orb-weaving family Araneidae, named for the angular, seven-sided outline of its abdomen. It builds a tidy, symmetrical wheel web in shrubs, tall grass, and garden edges, usually low to the ground compared to its larger orb-weaving relatives.
Coloring tends toward muted browns and tans that blend into dry vegetation, making this spider far easier to spot by its web than by its body. Like most orb weavers, it is completely harmless and plays an important role controlling small flying insects in Maryland gardens. Anyone wanting a sense of just how many orb-weaving relatives exist can check this overview of how many spider species exist worldwide.
9. Dark Fishing Spider
The dark fishing spider, Dolomedes tenebrosus, is one of the largest spiders found in Maryland, with females sometimes reaching a leg span of three inches or more. Its mottled brown and gray pattern provides excellent camouflage against tree bark, where it often rests head-down waiting for prey.
True to the “fishing spider” name, this species can walk across water surfaces and will dive underwater briefly to catch small fish, tadpoles, or aquatic insects near ponds and streams. On land, it hunts moths, beetles, and other insects along tree trunks and woodpiles. Despite its size, it is not aggressive toward people, and bites are rare and medically minor. Fishing spiders thrive in the wetland habitats common throughout the southern states as well, including the bayous covered in this guide to spiders found in Louisiana.
10. Jumping Spider
Jumping spiders, family Salticidae, are small, compact, and instantly recognizable by their oversized front eyes and surprisingly good vision for an arachnid. One common Maryland representative, the bold jumper (Phidippus audax), has a fuzzy black body accented with white or orange spots on the abdomen.
Rather than relying on webs, jumping spiders stalk prey like tiny cats, creeping close before leaping several times their own body length to strike. They’re frequently spotted on sunny walls, window screens, and porch railings during warmer months. Completely harmless to people, jumping spiders are often considered one of the more charismatic entries among backyard arachnids, much like the active hunters cataloged in this guide to spiders found in New York.
11. Crab Spider
Crab spiders earn their name from a sideways, crab-like gait and legs that project outward from the sides of the body rather than forward. Maryland’s crab spiders are bright white, yellow, or reddish, often perching motionless on flowers and leaves while waiting to ambush visiting pollinators.
The goldenrod crab spider (Misumena vatia) is among the most familiar species, and it can actually shift its body color between white and yellow over several days to better match the flower it’s hunting from. These spiders don’t build webs and rely entirely on patience and camouflage to capture bees, flies, and small butterflies. Similar ambush specialists show up across warmer climates too, as detailed in this look at spiders found in California.
12. Cobweb Spider
Cobweb spider is the general name for family Theridiidae, a group that includes the black widow but also dozens of smaller, harmless species found in Maryland gardens and homes. Most cobweb spiders build the irregular, tangled, three-dimensional webs that give the family its name, usually tucked into corners, eaves, or low vegetation.
Many species in this family are small, round-bodied, and brown or gray, making them easy to overlook unless the web itself draws attention. Globally, the cobweb spider family includes some well-known medically significant species, including Australia’s redback spider, a close widow-spider relative covered in this guide to spiders found in Australia.
13. Triangulate House Spider
The triangulate house spider, Steatoda triangulosa, has a distinctive pattern of brown triangular or zigzag markings across a tan or cream-colored abdomen. It’s one of the most common cobweb-building spiders found indoors in Maryland, often sharing the same basement corners and window frames as the common house spider.
This species is sometimes confused with its more notorious relatives because it belongs to the same genus as several false widow spiders, but it poses no meaningful risk to people. Triangulate house spiders feed on ants, flies, and other small household insects, making them a quietly useful presence rather than a nuisance. Homeowners further south deal with a similar mix of cobweb builders, as outlined in this guide to spiders found in Mississippi.
14. False Widow
False widow spiders belong to the genus Steatoda and are frequently mistaken for black widows because of their shiny, dark bodies. The most commonly encountered species, Steatoda grossa, lacks the complete red hourglass marking, usually showing a plain dark brown or purplish-black abdomen instead.
These spiders build the same loose, irregular cobwebs as their widow relatives and often colonize similar sheltered outdoor spots like window wells and shed corners. While a false widow bite can cause localized pain and swelling, it does not carry the systemic neurotoxic effects associated with true black widows. Correct identification matters here, and the same principle applies to misidentified species in other regions, like the widow look-alikes discussed in this guide to spiders found in Alabama.
Important Note: Several Maryland pest-control sources note that brown recluse sightings in the state are typically misidentified wolf spiders, false widows, or house spiders rather than confirmed established populations, since the species struggles to survive Maryland winters outdoors.
15. Yellow Sac Spider
The yellow sac spider, Cheiracanthium inclusum, is a pale yellow to light tan spider that builds a small, silken sac-like retreat rather than a hunting web. These sacs are often tucked into ceiling corners, behind picture frames, or folded inside curtains, where the spider hides during the day before emerging at night to hunt.
Yellow sac spiders are active nighttime hunters that roam walls and floors in search of insect prey. Their bite is one of the more noticeable among Maryland’s harmless species, sometimes causing localized redness and mild discomfort similar to a bee sting, though it resolves without medical treatment in most cases. For a closer comparison of how this species relates to its close relatives, this guide to sac spider species breaks down the wider family.
16. Joro Spider
The Joro spider, Trichonephila clavata, is a large, strikingly colored orb weaver native to East Asia that has been expanding its range across the southeastern United States in recent years. Females display bold yellow, blue-gray, and black banding across the legs and body, with a web that can span several feet between trees or utility lines.
Although Joro spiders are venomous in the technical sense that nearly all spiders are, their fangs are too small and their venom too mild to pose any real threat to people or pets. As this species continues to spread northward, Maryland residents may begin spotting its enormous golden-tinted webs more often, much as homeowners farther south already have in states profiled in this guide to spiders found in Montana, where range-expanding species are also being tracked.
Key Insight: Despite viral headlines calling it an invasive threat, entomologists generally classify the Joro spider as a nuisance rather than a danger, since it avoids confrontation and its bite rarely breaks human skin.
17. Spitting Spider
The spitting spider, Scytodes thoracica, has an unusual and highly effective hunting method: it immobilizes prey by spraying a sticky, venom-laced silk from its fangs in a zigzag pattern, pinning the target in place before moving in to bite. Its domed, mottled tan-and-brown cephalothorax gives it a somewhat bulbous, rounded appearance compared to most other house-dwelling spiders.
This slow-moving, six-eyed hunter prefers dark, humid spots like basements, closets, and bathroom corners, where it picks off small insects without ever building a traditional web. Spitting spiders are shy, rarely bite people, and are considered harmless even when they do. Their unusual hunting style places them among the more distinctive entries covered in broader guides to spiders found in Oklahoma.
18. European Garden Spider
The European garden spider, Araneus diadematus, is a large orb weaver with a distinctive cross-shaped pattern of white dots across its brown or orange abdomen, earning it the common nickname “cross spider.” It was introduced to North America from Europe and has since become established across much of the northeastern United States, including Maryland.
This spider builds a large, classic wheel web in gardens, eaves, and shrubs, often rebuilding it each night to repair damage from the previous day’s catches. European garden spiders are harmless to people and are considered beneficial predators of garden pests like aphids, moths, and flies. Their size and bold patterning make them one of the easier Maryland orb weavers to photograph and identify at a glance.
19. Spinybacked Orbweaver
The spinybacked orbweaver, Gasteracantha cancriformis, is instantly recognizable by its hard, shield-shaped abdomen studded with pointed red or black spines along the edges. The body is typically white or pale yellow with contrasting black spots, giving it an almost crab-shell appearance that sets it apart from every other spider on this list.
This species builds a fine, tightly woven orb web, often decorated with small tufts of silk called stabilimenta, strung between shrubs and low tree branches. Spinybacked orbweavers are harmless, slow-moving, and more common in Maryland’s warmer, humid months, with populations generally more abundant farther south. Residents comparing regional distribution can see how much more prevalent this species becomes in guides to spiders found in Florida.
20. Eastern Parson Spider
The eastern parson spider, Herpyllus ecclesiasticus, is a fast, ground-dwelling hunter named for a pale, cravat-like marking on its dark gray to black abdomen that resembles the old-fashioned clerical collar worn by parsons. Unlike many spiders on this list, it builds no web for hunting and instead chases down prey directly across floors, walls, and tree bark.
This species is a common nighttime visitor indoors during late summer and fall, often startling residents with its sudden bursts of speed. While a parson spider bite can occasionally cause a brief burning sensation, it is not considered medically significant and typically resolves quickly without treatment. Ground hunters like this one show up in similar numbers across neighboring states, as cataloged in this guide to spiders found in Missouri.
21. Black and Yellow Garden Spider
The black and yellow garden spider, Argiope aurantia, is one of the most visually dramatic spiders in Maryland, with a bold yellow-and-black patterned abdomen that can reach over an inch in length on mature females. It builds a large, vertical orb web featuring a distinctive thick zigzag band of silk down the center called a stabilimentum.
These spiders are commonly found in sunny gardens, tall grass, and field edges from midsummer through fall, when females reach their largest size before producing a papery egg sac. Despite their intimidating appearance, black and yellow garden spiders are harmless to people and rarely bite unless directly handled. Their striking web decorations make them one of the most photographed orb weavers across the entire mid-Atlantic region.
Maryland’s spider population ranges from the genuinely cautionary, like the black widow, to the purely beneficial, like garden-dwelling orb weavers that quietly thin out mosquito and fly populations all season long. Learning to recognize a handful of key features, glossy black bodies with red markings, web shape, hunting behavior, and typical hiding spots, makes it far easier to walk past a web with curiosity instead of alarm.