Triangulate bud spider (Steatoda triangulosa)

The triangulate bud spider is a spider in the family Theridiidae that is not dangerous to people. GBIF holds 1,603 licensed U.S. records of it; it reaches our listing threshold in 43 states, most of all Texas (400), Pennsylvania (107) and Ohio (76). Its observation records peak in August.

43states on record

1,603licensed U.S. records

Augpeak month, observations

Novenomous to people

The triangulate cobweb spider (scientific name: Steatoda triangulosa; also called the triangulate bud spider or checkered cobweb weaver) is a common spider in the genus Steatoda. It is well known for the triangle-shaped pattern on the dorsal side of its abdomen.

From Wikipedia: Triangulate cobweb spider, text under CC BY-SA 4.0.

Bitten? Call 911 for a venomous snakebite or any bite with trouble breathing. For advice on any bite or sting, call Poison Help at 1-800-222-1222 (free, 24/7, U.S.-wide). Do not cut the wound, suck out venom or use a tourniquet. General information, not medical advice. Do not handle or try to identify a snake or spider by this page; if unsure, treat it as venomous.

Is the triangulate bud spider poisonous or venomous?

Not in any medically significant way. Like almost all spiders the triangulate bud spider (family Theridiidae) has venom for its prey, but it is not a widow or recluse, the two U.S. groups whose bites need medical attention.

Often mistaken for

The triangulate bud spider is not dangerous to people, but people often take it for widow spiders (both are recorded in 41 of its 43 states).

Which states have the triangulate bud spider?

Records are spread over 43 states; the top three, Texas, Pennsylvania and Ohio, hold 36% of them.

Source: GBIF, read 2026-09-29. A state is listed once GBIF holds at least 10 records of the species there under any license; Records counts only CC0 and CC BY records, so a listed state can show fewer.
#	State	Records	Share of state spiders	Rank in state
1	Texas	400	1.4%	15th of 386
2	Pennsylvania	107	1.5%	13th of 164
3	Ohio	76	1.1%	22nd of 332
4	California	72	0.1%	75th of 309
5	Illinois	72	0.4%	41st of 243
6	Massachusetts	72	1.6%	13th of 189
7	New York	54	0.9%	29th of 149
8	Colorado	49	1.2%	14th of 378
9	Virginia	49	0.4%	52nd of 176
10	Maryland	42	0.7%	38th of 153
11	Tennessee	42	1.1%	22nd of 138
12	Michigan	41	1.7%	17th of 122
13	Utah	40	1.6%	9th of 97
14	North Carolina	39	0.5%	52nd of 184
15	Wisconsin	37	1.2%	15th of 149
16	Delaware	36	1.7%	15th of 71
17	Indiana	35	0.8%	24th of 133
18	Minnesota	34	1.1%	21st of 145
19	Oregon	27	1.0%	19th of 88
20	Kansas	26	1.6%	13th of 94
21	Oklahoma	26	0.5%	40th of 149
22	Missouri	25	1.1%	21st of 117
23	Louisiana	24	0.6%	35th of 107
24	Alabama	21	0.6%	47th of 143
25	Kentucky	21	1.1%	23rd of 103
26	New Jersey	18	0.8%	33rd of 127
27	Georgia	17	0.3%	75th of 186
28	Nebraska	14	1.1%	18th of 71
29	Connecticut	12	1.2%	22nd of 86
30	Iowa	12	1.8%	12th of 57
31	Arkansas	11	0.7%	37th of 114
32	South Carolina	11	0.5%	45th of 121
33	Idaho	9	1.7%	13th of 56
34	Washington	8	0.2%	61st of 157
35	Mississippi	6	0.4%	44th of 117
36	West Virginia	5	0.7%	30th of 90
37	Florida	3	0.0%	208th of 237
38	Nevada	3	0.6%	23rd of 47
39	Vermont	3	0.2%	46th of 74
40	New Mexico	2	0.1%	125th of 247
41	South Dakota	2	1.0%	18th of 29
42	Montana	0	—	—
43	Rhode Island	0	—	—

When is the triangulate bud spider seen?

Across the U.S., observation records of the triangulate bud spider run through most of the year, peaking in August with 13% of them. Winter (December to February) holds 15% of them.

Season by state

Observation records run through most of the year in California, Colorado, Illinois, Michigan, Minnesota, North Carolina and 3 more. Among states whose main season falls within one calendar year, it starts earliest in March (Virginia) and latest in May (Delaware and Indiana). The most common peak months are August and October, each shared by five states.

Source: GBIF observation records (CC0, CC BY) by state and month, read 2026-09-29. States with fewer than 30 observation records with a month are left out.
State	Main season	Peak month	Observation records
Texas	most of the year	April	393
Pennsylvania	most of the year	August	106
Ohio	most of the year	October	76
Massachusetts	April through December	October	72
Illinois	most of the year	September	63
California	most of the year	October	61
New York	May through January	July	52
Virginia	March through November	August	49
Colorado	most of the year	May	48
Tennessee	June through February	August	42
Maryland	April through September	August	40
Utah	April through October	August	40
North Carolina	most of the year	July	39
Michigan	most of the year	October	38
Wisconsin	May through January	November	37
Delaware	May through November	September	34
Minnesota	most of the year	December	34
Indiana	May through November	October	32

Where the triangulate bud spider is recorded in each state

Texas

Texas holds 400 licensed records, the 15th most recorded of 386 spiders listed there. Its observation records in Texas run through most of the year, peaking in April; most licensed records come from Dallas County, Travis County and Lubbock County. Next come Bexar County (24) and Collin County (21).

Pennsylvania

Pennsylvania holds 107 licensed records, the 13th most recorded of 164 spiders listed there. Its observation records in Pennsylvania run through most of the year, peaking in August; most licensed records come from Allegheny County, Montgomery County and Bucks County. Next come Philadelphia County (9) and Northampton County (7).

Ohio

Ohio holds 76 licensed records, the 22nd most recorded of 332 spiders listed there. Its observation records in Ohio run through most of the year, peaking in October; most licensed records come from Franklin County, Cuyahoga County and Richland County. Next come Summit County (5) and Butler County (5).

California

California holds 72 licensed records, the joint 75th most recorded of 309 spiders listed there. Its observation records in California run through most of the year, peaking in October; most licensed records come from Solano County, Los Angeles County and Napa County. Next come Orange County (5) and San Joaquin County (5).

Illinois

Illinois holds 72 licensed records, the 41st most recorded of 243 spiders listed there. Its observation records in Illinois run through most of the year, peaking in September; most licensed records come from Champaign County, Cook County and DuPage County. Next come Will County (2) and DeWitt County (2).

Massachusetts

Massachusetts holds 72 licensed records, the 13th most recorded of 189 spiders listed there. Its observation records in Massachusetts run mostly April through December, peaking in October; most licensed records come from Middlesex County, Suffolk County and Norfolk County. Next come Worcester County (4) and Plymouth County (3).

New York

New York holds 54 licensed records, the joint 29th most recorded of 149 spiders listed there. Its observation records in New York run mostly May through January, peaking in July; most licensed records come from Tompkins County, Monroe County and Erie County. Next come Richmond County (5) and Nassau County (4).

Colorado

Colorado holds 49 licensed records, the joint 14th most recorded of 378 spiders listed there. Its observation records in Colorado run through most of the year, peaking in May; most licensed records come from Boulder County, Larimer County and Jefferson County. Next come Denver County (5) and Douglas County (2).

Virginia

Virginia holds 49 licensed records, the 52nd most recorded of 176 spiders listed there. Its observation records in Virginia run mostly March through November, peaking in August; most licensed records come from Arlington County, Fairfax County and Montgomery County. Next come Albemarle County (4) and Fairfax City County (4).

Maryland

Maryland holds 42 licensed records, the 38th most recorded of 153 spiders listed there. Its observation records in Maryland run mostly April through September, peaking in August; most licensed records come from Prince George's County, Baltimore County and Montgomery County. Next come Anne Arundel County (4) and Howard County (3).

Tennessee

Tennessee holds 42 licensed records, the 22nd most recorded of 138 spiders listed there. Its observation records in Tennessee run mostly June through February, peaking in August; most licensed records come from Bradley County, Davidson County and Hamilton County. Next come Knox County (3) and Sevier County (2).

Michigan

Michigan holds 41 licensed records, the 17th most recorded of 122 spiders listed there. Its observation records in Michigan run through most of the year, peaking in October; most licensed records come from Wayne County, Washtenaw County and Charlevoix County. Next come Monroe County (4) and Ingham County (3).

Utah

Utah holds 40 licensed records, the joint 9th most recorded of 97 spiders listed there. Its observation records in Utah run mostly April through October, peaking in August; most licensed records come from Salt Lake County, Utah County and Davis County. Next come Iron County (1) and Weber County (1).

North Carolina

North Carolina holds 39 licensed records, the joint 52nd most recorded of 184 spiders listed there. Its observation records in North Carolina run through most of the year, peaking in July; most licensed records come from Cumberland County, Davidson County and Mecklenburg County. Next come Wake County (5) and Durham County (4).

Wisconsin

Wisconsin holds 37 licensed records, the joint 15th most recorded of 149 spiders listed there. Its observation records in Wisconsin run mostly May through January, peaking in November; most licensed records come from Dane County, Waukesha County and Brown County. Next come Eau Claire County (3) and Ozaukee County (2).

Delaware

Delaware holds 36 licensed records, the joint 15th most recorded of 71 spiders listed there. Its observation records in Delaware run mostly May through November, peaking in September; most licensed records come from Sussex County, New Castle County and Kent County.

Indiana

Indiana holds 35 licensed records, the joint 24th most recorded of 133 spiders listed there. Its observation records in Indiana run mostly May through November, peaking in October; most licensed records come from Marion County, Huntington County and Lake County. Next come Henry County (3) and Tippecanoe County (3).

Minnesota

Minnesota holds 34 licensed records, the 21st most recorded of 145 spiders listed there. Its observation records in Minnesota run through most of the year, peaking in December; most licensed records come from Hennepin County, Stevens County and Anoka County. Next come Blue Earth County (3) and Dakota County (2).

Top counties in the U.S.

Source: GBIF licensed records by county (GADM level 2), read 2026-09-29.
#	County	State	Records	Share of U.S.
1	Dallas County	Texas	107	6.7%
2	Travis County	Texas	54	3.4%
3	Lubbock County	Texas	35	2.2%
4	Salt Lake County	Utah	33	2.1%
5	Sussex County	Delaware	31	1.9%
6	Champaign County	Illinois	30	1.9%
7	Middlesex County	Massachusetts	27	1.7%
8	Bradley County	Tennessee	27	1.7%
9	Cook County	Illinois	25	1.6%
10	Suffolk County	Massachusetts	24	1.5%
11	Bexar County	Texas	24	1.5%
12	Allegheny County	Pennsylvania	23	1.4%
13	Collin County	Texas	21	1.3%
14	Boulder County	Colorado	20	1.2%
15	Montgomery County	Pennsylvania	18	1.1%

How recent are the triangulate bud spider records?

Most of what is known about the triangulate bud spider is recent: 93% of dated U.S. records were made in 2017–2026, and half date from 2023 or later. The oldest dated record is from 1936; the busiest year was 2025, with 327 records.

Source: GBIF licensed U.S. records with a year, read 2026-09-29.
Decade	Records	Share
1930s	1	0.1%
1960s	1	0.1%
1970s	1	0.1%
1980s	5	0.3%
1990s	6	0.4%
2000s	12	0.7%
2010s	283	16.9%
2020s	1,370	81.6%

Species recorded in the same counties

Of the 197 counties where the triangulate bud spider is most recorded, 142 are also top counties for the bold jumper, more than for any other spider. None of its closest neighbors is venomous.

Source: GBIF licensed records, top counties per species and state, read 2026-09-29.
Species	Shared counties
Bold jumper	142
Familiar jumping spider	111
Black-and-yellow argiope	108
Spotted orbweaver	104
Nursery web spider	98
Parson spider	98
Orchard orbweaver	95
Flea jumping spider	92

Other species of the genus Steatoda with profiles here: False black widow and Boreal combfoot.

Western black widowLatrodectus hesperusvenomous

False black widowSteatoda grossa

Brown widowLatrodectus geometricusvenomous

Common house spiderParasteatoda tepidariorum

Southern black widowLatrodectus mactansvenomous

Northern black widowLatrodectus variolusvenomous

Common six-spotted cobweaverRugathodes sexpunctatus

Boreal combfootSteatoda borealis

GBIF records read 2026-09-29. Listed: any license. Counted: CC0/CC BY only. How we count.

About these numbers

A species is listed for a state once GBIF holds at least 10 records of it located inside the state by coordinates, under any license. Every count, share, month and county shown is computed only from records published under CC0 or CC BY, so a listed species can show few or no counted records. Monthly patterns show when people record spiders, which also reflects when people are outdoors. Venomous status follows taxonomy: pit vipers and coral snakes; widow and recluse spiders; the Arizona bark scorpion. Records filed under older names count for the species they belong to today. Full methodology.