Bay Area blonde (Aphonopelma iodius)
The Bay Area blonde is a spider in the family Theraphosidae that is not dangerous to people. GBIF holds 412 licensed U.S. records of it; it reaches our listing threshold in 4 states, most of all California (320), Utah (64) and Nevada (27). Its observation records peak in September.
Aphonopelma iodius is a species of spider in the tarantula family Theraphosidae, found in United States (California, Nevada, Arizona and Utah). A 1997 paper combined it with three other previously described species (A. angusi, A. melanium, and A. nevadanum) into a single species, calling it "A. iodium". However, iodius is a neuter comparative adjective and is the correct form.
From Wikipedia: Aphonopelma iodius, text under CC BY-SA 4.0.
Is the Bay Area blonde poisonous or venomous?
Not in any medically significant way. Like almost all spiders the Bay Area blonde (family Theraphosidae) 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 Bay Area blonde?
The Bay Area blonde's U.S. record is concentrated: California alone holds 78% of licensed records. It is listed in 4 states in all; the next are Utah (64), Nevada (27) and Arizona (1).
| # | State | Records | Share of state spiders | Rank in state |
|---|---|---|---|---|
| 1 | California | 320 | 0.6% | 25th of 309 |
| 2 | Utah | 64 | 2.6% | 5th of 97 |
| 3 | Nevada | 27 | 5.0% | 3rd of 47 |
| 4 | Arizona | 1 | 0.0% | 139th of 162 |
When is the Bay Area blonde seen?
Across the U.S., observation records of the Bay Area blonde run mostly May through November, peaking in September with 32% of them. Winter (December to February) holds 4% of them.
Season by state
Among states whose main season falls within one calendar year, it starts earliest in May (California) and latest in July (Utah). Each of these states peaks in a different month: August in Utah and September in California.
| State | Main season | Peak month | Observation records |
|---|---|---|---|
| California | May through November | September | 320 |
| Utah | July through November | August | 64 |
Where the Bay Area blonde is recorded in each state
California
California holds 320 licensed records, the 25th most recorded of 309 spiders listed there. Its observation records in California run mostly May through November, peaking in September; most licensed records come from Contra Costa County, Santa Clara County and San Luis Obispo County. Next come San Bernardino County (28) and Alameda County (23).
Utah
Utah holds 64 licensed records, the 5th most recorded of 97 spiders listed there. Its observation records in Utah run mostly July through November, peaking in August; most licensed records come from Washington County, Salt Lake County and Iron County. Next come Kane County (1) and San Juan County (1).
Top counties in the U.S.
| # | County | State | Records | Share of U.S. |
|---|---|---|---|---|
| 1 | Contra Costa County | California | 136 | 33.0% |
| 2 | Santa Clara County | California | 42 | 10.2% |
| 3 | San Luis Obispo County | California | 34 | 8.3% |
| 4 | Washington County | Utah | 34 | 8.3% |
| 5 | San Bernardino County | California | 28 | 6.8% |
| 6 | Alameda County | California | 23 | 5.6% |
| 7 | Salt Lake County | Utah | 18 | 4.4% |
| 8 | Inyo County | California | 15 | 3.6% |
| 9 | Monterey County | California | 11 | 2.7% |
| 10 | San Benito County | California | 8 | 1.9% |
| 11 | Riverside County | California | 7 | 1.7% |
| 12 | Kern County | California | 5 | 1.2% |
| 13 | Santa Barbara County | California | 5 | 1.2% |
| 14 | Iron County | Utah | 5 | 1.2% |
| 15 | San Mateo County | California | 3 | 0.7% |
How recent are the Bay Area blonde records?
Most of what is known about the Bay Area blonde is recent: 80% of dated U.S. records were made in 2017–2026, and half date from 2021 or later. The oldest dated record is from 2001; the busiest year was 2023, with 58 records.
| Decade | Records | Share |
|---|---|---|
| 2000s | 16 | 3.9% |
| 2010s | 139 | 33.7% |
| 2020s | 258 | 62.5% |
Species recorded in the same counties
Of the 25 counties where the Bay Area blonde is most recorded, 17 are also top counties for the western black widow, more than for any other spider. Venomous species among its neighbors: the western black widow.
| Species | Shared counties |
|---|---|
| Western black widow venomous | 17 |
| Banded garden spider | 15 |
| Bold jumper | 12 |
| Pelegrina aeneola | 12 |
| Dysdera crocata | 11 |
| Triangulate bud spider | 10 |
| Western spotted orbweaver | 10 |
| California flattened jumping spider | 9 |
Related species in the U.S.
Other species of the genus Aphonopelma with profiles here: Texas brown tarantula and Desert blond tarantula.
GBIF records read 2026-09-29. Listed: any license. Counted: CC0/CC BY only. How we count.