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A female joro spider resting on her web against green foliage, the long abdomen yellow with blue grey bands and a red patch beneath, the legs black with yellow bands

Spider Season in Maryland: What Lives Here and When It Comes Indoors

2 widow or recluse species have verified records in Maryland, and the joro spider has been recorded since 2022. The indoor season, a live range map, and the lookalikes.

Spiders are moving indoors in Maryland now
Widow and recluse species
2
Joro spider
Recorded since 2022
Indoor season
Aug 20 to Nov 20

Spiders in Maryland, by the numbers

Verified records, snapshot 2026-09-19 since 2022
Today
When spiders wander indoors in Maryland, against the second half of the year. The peak shifts a week or two with the first hard frost.
2
widow and recluse species
Northern black widow, Southern black widow
72
joro records
earliest 2022
Sep 10 to Oct 20
peak indoor season
wandering males and grown females
801
widow and recluse records
iNaturalist snapshot

Maryland has the largest joro footprint north of the Carolinas, 72 verified records since 2022 around Baltimore, and both eastern black widows in roughly equal numbers. Its 7 brown recluse records sit below the threshold; the recluse is not part of the state's established fauna.

The joro spider

Joro spiders in Maryland, recorded since 2022

Maryland has 72 verified joro spider records, the earliest from 2022. The records cluster where people live and photograph, on porches, fence lines, power line corridors and tree edges, and the year peaks in September and October when females reach full size and their golden webs become impossible to miss.

Where the years come from. The joro spider was first confirmed in North America in 2014, from specimens collected in Barrow, Jackson and Madison counties, northeast Georgia (Hoebeke, Huffmaster and Freeman (2015), PeerJ 3:e763). Every other year on this page is a first iNaturalist record, which runs later than the collections a species is established on.

Joro spider records in Maryland, by month
013253850January: 0 recordsJFebruary: 0 recordsFMarch: 0 recordsMApril: 0 recordsAMay: 0 recordsMJune: 1 recordsJJuly: 7 recordsJAugust: 14 recordsASeptember: 42 recordsSOctober: 6 recordsONovember: 2 recordsNDecember: 0 recordsD
72 research grade joro records in Maryland, grouped by the month observed. The highlighted bars are September and October.From the iNaturalist snapshot taken 2026-09-19.
A female joro spider resting on her web against green foliage, the long abdomen yellow with blue grey bands and a red patch beneath, the legs black with yellow bands
A female joro spider at full size: yellow with blue grey bands, a red patch beneath, legs banded black and yellow. An orbweaver, and of no medical concern. “Joro Spider - Trichonephila clavata (50564813031)” by Christina Butler from Georgia, United States, CC BY 2.0
A yellow garden spider head down at the centre of her web, egg shaped black and yellow abdomen, black legs with orange bases, and a thick white zigzag of silk below her
The yellow garden spider, native and the spider most often reported as a joro. The egg shaped patterned abdomen and the white zigzag in the web are the tells. “Argiope aurantia in web” by AmaryllisGardener, CC BY-SA 3.0
The list

The 2 widow and recluse species recorded in Maryland

Every species below has verified, photograph backed records in Maryland. The counts come from iNaturalist and measure how often people find and photograph each spider, never how many there are: a species of packrat nests will always look rarer than one of garages.

SpeciesGroupVerified recordsWhat to look for
Northern black widow
Latrodectus variolus
Widow445The hourglass is usually split into two red bars, often with a row of red spots along the top of the abdomen. Woodland edges, stumps, stone walls and old outbuildings; the widow of the Northeast and the Great Lakes.
Southern black widow
Latrodectus mactans
Widow356Glossy black with a round abdomen and a complete red hourglass underneath. Tangle webs low down in woodpiles, meter boxes, under outdoor furniture and in the corners of sheds.
A glossy black widow spider hanging upside down in her web on coarse cloth, the red hourglass on the underside of the round abdomen in full view
A black widow from below: the red hourglass on a glossy round abdomen, hanging upside down in a low tangle web. The northern black widow's hourglass is usually split in two. “Adult Female Black Widow” by Shenrich91, CC BY-SA 3.0
A barn funnel weaver on a white ceiling seen from above, brown with two dark stripes on the front body segment and a mottled abdomen, its legs spread wide
For contrast, the barn funnel weaver that makes up most of the autumn indoor record: striped front segment, mottled abdomen, a sheet web with a funnel. Of no medical concern. “Tegenaria-domestica-chb” by Chb, CC BY 3.0
Interactive

Where each species has been found in Maryland

Pick a species. The coloured cells are places where somebody photographed one and the identification was confirmed, redrawn as records are added. It thins over roadless country and thickens around towns, because that is where people look.

Style
Size

Coloured cells are verified Trichonephila clavata records on iNaturalist, brighter where more have been logged. This is where people have found and photographed the species, so it thins out over roadless country and thickens around parks and towns. It is a record map, not a drawn range boundary. See the underlying records.

The season

When spiders come indoors in Maryland

Indoor sightings in Maryland pick up around August 20, peak between September 10 and October 20, and fade by November 20. The wanderers are mature male house spiders and funnel weavers searching for females, plus spring hatched spiders that have finally grown large enough to see. The widow spiders follow the same calendar because females are at full size; the busiest month in the Maryland record is June.

Widow spider records in Maryland, by month
050100150200January: 5 recordsJFebruary: 4 recordsFMarch: 17 recordsMApril: 45 recordsAMay: 122 recordsMJune: 157 recordsJJuly: 104 recordsJAugust: 111 recordsASeptember: 102 recordsSOctober: 98 recordsONovember: 27 recordsNDecember: 11 recordsD
803 research grade records of widow spiders in Maryland, grouped by the month observed.From the iNaturalist snapshot taken 2026-09-19.

What the chart counts. Records, and a record needs a spider and a person with a camera. Spring spikes in some states are a late April bioblitz. Switch to the effort adjusted view and each month is divided by every research grade observation logged in Maryland that month, which strips most of that out. Neither view is a population count.

A large dark funnel weaver spider standing in the white basin of a bathtub, long legs spread on the enamel
A funnel weaver in a bathtub, the classic September find. Smooth enamel is the one surface a wandering male cannot climb back out of, which is why the tub and the sink collect them. “Spinne-Tegenaria-domestica 01” by Traumrune, CC BY-SA 3.0
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Identification

The spiders people photograph as widows

Most spiders reported as a widow or a recluse in Maryland are one of the species below. The tells are visible from a comfortable distance, and a spider left alone in its corner stays there.

A widow is glossy, round bodied, and hangs upside down in a low tangle web with a red or orange hourglass underneath. A recluse is plain tan with six eyes in three pairs, a darker violin on the front segment, and legs with no bands and no spines. A violin shaped mark on its own is not a recluse: many harmless brown spiders carry one, and it is faint on many real recluses. A bite is never an identification. Skin reactions have dozens of causes, and Poison Control on 1-800-222-1222 will ask about symptoms, never for a species name.

Mistaken for a black widow

False widow

Steatoda grossa

Purplish brown rather than glossy black, with pale markings on top of the abdomen and nothing underneath. The same tangle web in the same corners, which is why it is photographed as a widow more than any other spider.

Triangulate cobweb spider

Steatoda triangulosa

Small, brown, with a row of pale triangles down the abdomen. Lives in the same low corners and window frames a widow would, and turns up indoors far more often.

Common house spider

Parasteatoda tepidariorum

Mottled tan and brown with a rounded abdomen, in messy cobwebs in ceiling corners, under eaves and behind furniture. The most photographed spider in American houses, and an autumn indoor regular.

Mistaken for a joro spider

Yellow garden spider

Argiope aurantia

Black and yellow, but the abdomen is egg shaped with a bold black and yellow pattern rather than banded, the legs are black with a yellow base instead of banded along their length, and the web has a thick zigzag of white silk down the middle. Native, and in every state.

Banded garden spider

Argiope trifasciata

Silvery white with thin black and yellow bands across the abdomen, on a wheel shaped web in tall grass and gardens in late summer. Smaller than a joro, with shorter legs and no red underneath.

Golden silk orbweaver

Trichonephila clavipes

The joro's native cousin across the Deep South. Orange brown rather than yellow and black, with tufts of dark hair on the leg joints and no red patch. It has been in the Southeast for as long as there are records.

If someone is bitten

What to do about a spider bite in Maryland

First
Wash the bite with soap and water. That is the whole of the first aid. Skip creams, heat, ice and anything from a kitchen cupboard.
Then
Call Poison Control on 1-800-222-1222. Free, staffed around the clock, and they will tell you what to watch for over the next hours. They ask about symptoms, never for a species name.
Go to a hospital
For muscle cramping, sweating, spreading pain, or a wound that keeps getting worse over a day or two. Those are the signs that matter after a widow or recluse bite, and treatment depends on them, never on identifying the spider.
About the spider
A bite is never an identification. Skin reactions have dozens of causes and most marks blamed on spiders are something else. If the spider is already dead and in a container, bring it; never hunt for one.

Poison Control: 1-800-222-1222, any time, any state.

Common questions

Maryland spider season FAQ

Also indoors this season

The rest of your Maryland autumn

More Southeast spider season pages

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Species lists, record counts and monthly curves are research grade observations from the iNaturalist API, aggregate counts only, snapshot 2026-09-19 with the curves read live in your browser. They measure how often people find and photograph a species, never how many there are, and a species with no record here may still live here. Season windows are drawn from those curves and are climatological typicals. See every record behind this page. For any bite, wash with soap and water and call Poison Control on 1-800-222-1222. National picture: spider season by state.
Hero image: “Joro Spider - Trichonephila clavata (50564813031)” by Christina Butler from Georgia, United States, CC BY 2.0