Spiny-backed orbweaver (Gasteracantha cancriformis)
The spiny-backed orbweaver is a spider in the family Araneidae that is not dangerous to people. GBIF holds 2,411 licensed U.S. records of it; it reaches our listing threshold in 17 states, most of all Florida (864), Texas (751) and Georgia (138). Its observation records peak in September.
Gasteracantha cancriformis (spinybacked orbweaver) is a species of orb-weaver spider (family Araneidae). It is widely distributed in the New World. The genus name Gasteracantha derives from the Ancient Greek γαστήρ (gastḗr), meaning "belly", and ἄκανθα (ákantha), meaning "thorn", while the specific epithet cancriformis derives from the Latin words cancer ("crab") and forma ("shape, form, appearance").
From Wikipedia: Gasteracantha cancriformis, text under CC BY-SA 4.0.
Is the spiny-backed orbweaver poisonous or venomous?
Not in any medically significant way. Like almost all spiders the spiny-backed orbweaver (family Araneidae) has venom for its prey, but it is not a widow or recluse, the two U.S. groups whose bites need medical attention.
Which states have the spiny-backed orbweaver?
Records are spread over 17 states; the top three, Florida, Texas and Georgia, hold 73% of them.
| # | State | Records | Share of state spiders | Rank in state |
|---|---|---|---|---|
| 1 | Florida | 864 | 6.9% | 2nd of 237 |
| 2 | Texas | 751 | 2.6% | 6th of 386 |
| 3 | Georgia | 138 | 2.1% | 9th of 186 |
| 4 | Louisiana | 131 | 3.3% | 7th of 107 |
| 5 | North Carolina | 127 | 1.5% | 13th of 184 |
| 6 | Alabama | 94 | 2.6% | 7th of 143 |
| 7 | South Carolina | 89 | 3.7% | 5th of 121 |
| 8 | Virginia | 64 | 0.6% | 42nd of 176 |
| 9 | Mississippi | 46 | 3.2% | 5th of 117 |
| 10 | Hawaii | 30 | 0.6% | 23rd of 57 |
| 11 | Delaware | 20 | 0.9% | 28th of 71 |
| 12 | Maryland | 20 | 0.4% | 63rd of 153 |
| 13 | California | 16 | 0.0% | 188th of 309 |
| 14 | Arkansas | 7 | 0.4% | 52nd of 114 |
| 15 | Tennessee | 7 | 0.2% | 76th of 138 |
| 16 | New Jersey | 2 | 0.1% | 102nd of 127 |
| 17 | Oklahoma | 2 | 0.0% | 128th of 149 |
When is the spiny-backed orbweaver seen?
Across the U.S., observation records of the spiny-backed orbweaver run through most of the year, peaking in September with 16% of them. Winter (December to February) holds 20% of them.
Season by state
Observation records run through most of the year in Florida. Among states whose main season falls within one calendar year, it starts earliest in April (Louisiana and Texas) and latest in August (Alabama). The most common peak month is September, shared by Alabama, Georgia, Louisiana, Mississippi and North Carolina.
| State | Main season | Peak month | Observation records |
|---|---|---|---|
| Florida | most of the year | January | 829 |
| Texas | April through December | October | 737 |
| Georgia | May through November | September | 138 |
| Louisiana | April through October | September | 131 |
| North Carolina | June through October | September | 118 |
| Alabama | August through December | September | 93 |
| South Carolina | May through November | August | 78 |
| Virginia | June through October | July | 64 |
| Mississippi | May through October | September | 46 |
| Hawaii | November through May | April | 30 |
Where the spiny-backed orbweaver is recorded in each state
Florida
Florida holds 864 licensed records, the 2nd most recorded of 237 spiders listed there. Its observation records in Florida run through most of the year, peaking in January; most licensed records come from Broward County, Monroe County and Miami-Dade County. Next come Alachua County (65) and Lee County (62).
Texas
Texas holds 751 licensed records, the 6th most recorded of 386 spiders listed there. Its observation records in Texas run mostly April through December, peaking in October; most licensed records come from Hidalgo County, Harris County and Travis County. Next come Cameron County (41) and Brazos County (36).
Georgia
Georgia holds 138 licensed records, the 9th most recorded of 186 spiders listed there. Its observation records in Georgia run mostly May through November, peaking in September; most licensed records come from Chatham County, DeKalb County and Bryan County. Next come Cobb County (9) and Richmond County (7).
Louisiana
Louisiana holds 131 licensed records, the 7th most recorded of 107 spiders listed there. Its observation records in Louisiana run mostly April through October, peaking in September; most licensed records come from East Baton Rouge Parish, Orleans Parish and Saint Tammany Parish. Next come Jefferson Parish (11) and Calcasieu Parish (6).
North Carolina
North Carolina holds 127 licensed records, the 13th most recorded of 184 spiders listed there. Its observation records in North Carolina run mostly June through October, peaking in September; most licensed records come from Wake County, New Hanover County and Mecklenburg County. Next come Orange County (10) and Durham County (9).
Alabama
Alabama holds 94 licensed records, the 7th most recorded of 143 spiders listed there. Its observation records in Alabama run mostly August through December, peaking in September; most licensed records come from Blount County, Tuscaloosa County and Jefferson County. Next come Lee County (8) and Mobile County (7).
South Carolina
South Carolina holds 89 licensed records, the 5th most recorded of 121 spiders listed there. Its observation records in South Carolina run mostly May through November, peaking in August; most licensed records come from Charleston County, Richland County and Chesterfield County. Next come Beaufort County (6) and Greenville County (5).
Virginia
Virginia holds 64 licensed records, the joint 42nd most recorded of 176 spiders listed there. Its observation records in Virginia run mostly June through October, peaking in July; most licensed records come from Virginia Beach, Norfolk and Accomack County. Next come Stafford County (4) and Northampton County (4).
Mississippi
Mississippi holds 46 licensed records, the 5th most recorded of 117 spiders listed there. Its observation records in Mississippi run mostly May through October, peaking in September; most licensed records come from Jackson County, Pearl River County and Adams County. Next come Madison County (3) and Simpson County (3).
Hawaii
Hawaii holds 30 licensed records, the 23rd most recorded of 57 spiders listed there. Its observation records in Hawaii run mostly November through May, peaking in April; most licensed records come from Kauai County, Maui County and Hawaii County.
Top counties in the U.S.
| # | County | State | Records | Share of U.S. |
|---|---|---|---|---|
| 1 | Hidalgo County | Texas | 172 | 7.1% |
| 2 | Broward County | Florida | 160 | 6.6% |
| 3 | Monroe County | Florida | 110 | 4.6% |
| 4 | Miami-Dade County | Florida | 97 | 4.0% |
| 5 | Harris County | Texas | 79 | 3.3% |
| 6 | Alachua County | Florida | 65 | 2.7% |
| 7 | Lee County | Florida | 62 | 2.6% |
| 8 | Palm Beach County | Florida | 55 | 2.3% |
| 9 | Travis County | Texas | 43 | 1.8% |
| 10 | Pinellas County | Florida | 42 | 1.7% |
| 11 | Cameron County | Texas | 41 | 1.7% |
| 12 | Brazos County | Texas | 36 | 1.5% |
| 13 | Bexar County | Texas | 34 | 1.4% |
| 14 | East Baton Rouge Parish | Louisiana | 33 | 1.4% |
| 15 | Charleston County | South Carolina | 30 | 1.2% |
How recent are the spiny-backed orbweaver records?
Most of what is known about the spiny-backed orbweaver is recent: 91% of dated U.S. records were made in 2017–2026, and half date from 2021 or later. The oldest dated record is from 1936; the busiest year was 2021, with 359 records.
| Decade | Records | Share |
|---|---|---|
| 1930s | 1 | 0.0% |
| 1980s | 14 | 0.6% |
| 2000s | 23 | 0.9% |
| 2010s | 588 | 23.7% |
| 2020s | 1,856 | 74.8% |
Species recorded in the same counties
Of the 138 counties where the spiny-backed orbweaver is most recorded, 81 are also top counties for the black-and-yellow argiope, more than for any other spider. None of its closest neighbors is venomous.
| Species | Shared counties |
|---|---|
| Black-and-yellow argiope | 81 |
| Magnolia green jumper | 78 |
| Spotted orbweaver | 72 |
| Twin-flagged jumping spider | 69 |
| American golden orb weaver | 66 |
| Familiar jumping spider | 65 |
| Green lynx spider | 63 |
| Rabid wolf spider | 61 |
Related species in the U.S.
Other members of the family Araneidae with profiles here: Black-and-yellow argiope, Spotted orbweaver, Garden spider, American golden orb weaver, Spined micrathena and Banded garden spider.
GBIF records read 2026-09-29. Listed: any license. Counted: CC0/CC BY only. How we count.