Yellow sac spider bites in Texas
Texas has 110 verified yellow sac spider records in the GBIF biodiversity database — one of the highest counts in the country. Sightings concentrate in April to June. The bite itself appears stinging pain at the time of the bite and lasts about a week.
| Verified records | 110 |
|---|---|
| Peak sightings | April to June |
| State bite season | February to December |
| Active | night |
| Habitat | ceiling corners, curtain folds and wall junctions indoors; this is a common household spider nationwide |
| Bite appears | stinging pain at the time of the bite |
Identifying it in Texas
Small, pale yellow-green, and the spider most likely to bite a sleeping person indoors. The bite stings at the time, unlike a bed bug, and appears singly rather than in a line — the two are otherwise easy to confuse because both happen overnight on uncovered skin.
Locally, the species most often confused with it are honey bee sting, fire ant sting, carpenter ant bite — all of which are also recorded in Texas.
Seek medical care if
- an enlarging ulcer
- spreading redness with fever
What else it could be in Texas
These are recorded in Texas too and are the ones most often confused with it here. The differences below are the ones that actually separate them.
| Yellow sac spider bite | Brown recluse spider bite | Bed bug bite | |
|---|---|---|---|
| Pattern | single, sometimes two nearby | single site | lines or zigzags of three or more — the classic "breakfast, lunch and dinner" |
| Where on body | neck, arms, torso — often bites received in bed | torso under clothing, upper arms, thighs — often where clothing was put on with the spider inside | arms, shoulders, neck |
| Appears | stinging pain at the time of the bite | often painless at first | hours to several days — many people notice nothing on the first night |
| Records here | 110 | 1,150 | 65 |
Season in Texas specifically
Records in Texas concentrate in April to June, which is what local sighting data shows rather than a national average — seasonality shifts substantially with latitude. The general bite season in Texas runs February to December.
Because ceiling corners, curtain folds and wall junctions indoors, exposure in Texas tends to be concentrated in specific places rather than spread evenly — which is why a bite history ("where were you in the 24 hours before?") narrows the answer faster than the appearance of the mark.
Care
- wash, cold pack, antihistamine if itchy
- keep the area clean while it heals
Avoiding them in Texas
- vacuum ceiling corners and behind curtains
- seal gaps around window frames
Questions
When are yellow sac spiders active in Texas?
Texas records peak in April to June. The general bite season in Texas runs February to December.
Are they common in Texas?
Texas accounts for 110 verified records in GBIF, ranking it 5th among states for this species. Records reflect reporting effort as well as abundance.
What does the bite look like?
a red, tender bump, occasionally with a small blister, red, sometimes with a pale centre. Single, sometimes two nearby.
Get a photo assessment in the app
Everything above is free to read. The app adds what a page cannot: point your camera at the bite and get an assessment of the most likely cause, a severity read, and a day-by-day care plan — including the specific signs that mean you should be seen.
iPhone and iPad. Free to download.