Spiders in South Texas Homes: Brown Recluse, Widows and the Rest

Most spiders in San Antonio-area homes are a nuisance, not a danger. Only two groups in Texas matter medically: recluses such as the brown recluse, and the widows. Both live indoors and outdoors throughout the state. If you find either one inside, cut clutter, shake out stored items, set sticky traps and have the house inspected, because sprays alone rarely solve spider problems.

To have a technician check your home, call or text (210) 281-1064 or book online.

Is it a brown recluse? #

Texas A&M AgriLife's spider guide, E-408, describes the brown recluse this way:

• Light to dark brown, with long, slender legs that have no spines
• Spans roughly a quarter to a half-dollar coin with legs out; the body itself is about 1/4 to 1/2 inch
• A dark fiddle shape behind the eyes, with the fiddle's neck aimed toward the rear
• Six eyes set in three pairs (most spiders have eight)

The violin can be faint and can resemble markings on other spiders. An AgriLife IPM specialist recommends judging by size, color and the eye arrangement instead. Texas has five recluse species, and all are venomous.

Recluses are shy and hunt after dark. They don't use webs to catch prey; their loose silk mostly serves as a retreat and egg site. Outdoors they hide under firewood, rocks, boards and loose bark. Indoors they favor attics, crawl spaces, wall voids, closets and cardboard boxes. Their Texas mating season runs from April into early July, and adults turn up most often in spring.

Is it a black widow? #

Four widow species live in Texas: the southern, western and northern black widows and the introduced brown widow. AgriLife's guide to venomous animals calls all four dangerous.

• The adult female black widow is shiny jet black with a round abdomen and a red or yellowish hourglass underneath. On some spiders the mark is broken into two pieces or missing.
• Size estimates differ. UC IPM puts a mature female's body at about 1/2 inch, while Texas A&M lists an average of 1 1/2 inches.
• Males are much smaller than females.
• The brown widow is mottled tan, brown and gray, and its venom is much milder.

Widows build messy, sticky, irregular webs close to the ground and hang upside down in them. Look in woodpiles, garages, shrubs, rain spouts, gas and electric meter boxes, under eaves and in other places that are rarely disturbed.

What are the look-alikes? #

Plenty of common Texas spiders get mistaken for the dangerous ones:

• Wolf spiders are hairy, drab and often striped, with two big eyes sitting high on the head and no fiddle mark. They roam after dark, often walk in under doors and aren't considered dangerous to people or pets.
• Spitting spiders have an eye pattern like a recluse but long, banded legs and a spotted, domed front body. They are slow and pose no threat.
• False black widows are a dark chocolate color and lack any red underneath. Their bite is often compared to a yellowjacket sting.
• Cellar spiders have very long legs and cause trouble mainly with cobwebs. Daddy longlegs (harvestmen) aren't spiders at all and have no venom.
• Orbweavers and jumping spiders are common in Texas gardens and don't pose a medical concern.

Texas brown tarantulas are shy, and their bites aren't dangerous, though their hairs can irritate skin and eyes. The large wasps that hunt them are covered in our tarantula hawk guide.

What happens after a spider bite? #

Spiders don't hunt people. Recluses bite when trapped against skin, such as when a sleeper rolls over on one, a shirt with one inside gets pulled on or someone digs through a garage. The CDC notes a recluse can't bite without that pressure.

• Recluse bite: It may not hurt at first, then becomes painful 2 to 8 hours later. A blister can form within about a day, and a slow-healing sore may develop within a week. Severe cases can require surgery. AgriLife adds that staph and other bacteria cause sores that look the same, so many "spider bites" are something else.
• Widow bite: The venom affects the nerves. Within 1 to 3 hours it can cause widespread pain lasting 2 to 3 days, along with cramps, sweating and vomiting. Children, older people and those already ill tend to react worst, though deaths are rare.

First aid, per DSHS: clean the bite using soap and water, hold ice on it and capture the spider if that won't get you bitten. The Texas Poison Center Network (1-800-222-1222) or your own doctor can advise you, and any suspected widow or recluse bite deserves medical care. DSHS notes there is no effective antivenom for brown recluse bites.

Why are there more spiders in the house? #

Spiders follow food. Outdoor lights draw insects, and spiders set up around lit doors and windows to catch them. AgriLife also says drought and the first cool weather of fall push spiders, along with scorpions, inside. If you have lots of insects, such as cockroaches, spiders often come with them.

Clues to a growing indoor population include cobwebs in room corners and under eaves, messy low webs in the garage, round egg sacs, and spiders caught on glue boards or found inside boxes and footwear.

What can you do to reduce spiders? #

• Before you use stored clothing, shoes or linens, give them a hard shake.
• Put on gloves before handling boxes, firewood or yard debris.
• Store items in plastic bins with tight lids and tape the seams of cardboard boxes.
• Use a hand vacuum to remove spiders, webs and egg sacs, then empty it outside.
• Set sticky traps under furniture, inside closets and against baseboards.
• Weatherstrip doors and windows and caulk gaps around pipes and wires.
• Keep woodpiles well away from walls and cut back shrubs that touch the house.
• Switch to yellow bug lights or aim lights away from doors.

Do sprays work on spiders? #

Only partly. AgriLife says spiders tolerate insecticides better than most indoor insects and often sit on webs above treated surfaces, so cleaning and physical removal matter most. DSHS says store-bought products often lack the strength needed and that a professional can apply a longer-lasting treatment around the outside of the building. Foggers only reach spiders that are out in the open.

Brown recluses are the hardest. AgriLife's brown recluse fact sheet says even professionals find infestations difficult and that a mix of sanitation, sticky traps and treatment is usually needed. Clearing clutter before the technician arrives helps. For widows, UC IPM says insecticides don't give lasting control outdoors; removing webs and hiding spots matters more.

How does Pest Trappers handle spiders? #

We handle spiders in homes and businesses across San Antonio, Helotes, Leon Springs and The Dominion, Boerne and Fair Oaks Ranch.

• Inspection and ID. The technician identifies the spiders you're seeing and checks attics, garages, closets, eaves and the insects drawing them in.
• Options. You'll get a plan that mixes cleanup and sealing steps with any treatment, plus advice on traps for monitoring.
• Label rules. Only products labeled for spiders are used, exactly as the label directs. The work is done under Pest Trappers LLC (TPCL #0887549), a family-owned San Antonio company.

Pricing is quoted after the inspection. Book online or call or text (210) 281-1064, and the office will confirm your time. Se habla español.

Frequently asked questions #