Most Poisonous Spiders in Texas | Venomous Risk

Texas has over 900 species of spiders but only four of them pose a risk to humans. These spiders possess venom which is designed to knock out small insects, not people. They are not aggressive creatures but will bite if disturbed, trapped, or otherwise provoked. 

Most Venomous Spider in Texas

The most poisonous species of spider found in Texas is considered to be the Black Widow.

A black widow spider can be identified by its solid black color and globular abdomen. Their venom is reported to be 15 times more toxic than the venom of a prairie rattlesnake. However, only a very small amount is released and the most extreme reactions tend to occur in children and older adults who should seek medical attention as soon as possible. 

Poisonous Spiders in Texas Identification

Let’s take a look now at the most poisonous spiders in Texas including details of how to recognize them if you were to stumble across one and where to find them if you’d rather not happen across them!

Black Widow

Scientific Name: Latrodectus mactans

Black Widow
Adult Female Black Widow
Credit: Shenrich91 by CC 3.0

This species of spider has extremely poisonous venom which contains the neurotoxin latrotoxin. If you see one on your property, it’s likely that there are more nearby. 

They are frequently found in boxes, eaves, woodpiles, and other undisturbed areas. Contrary to popular belief, the female is only likely to consume the male when kept in a cage where he is unable to escape. 

Indigenous to the south-eastern United States, these spiders range from Ohio to Texas and northern Black Widows occur in British Columbia, Alberta, and the Dominican Republic. 

They can move very quickly when they feel trapped. Reactions to bites are seldom serious but you should seek medical attention because if the bite is severe, you may need a muscle relaxant. Symptoms usually begin after around 30 minutes. 

Brown Recluse

Scientific Name: Loxosceles reclusa

Brown Recluse
This brown recluse or violin spider (Loxosceles reclusa) is a species of spider native to North America
Credit: Rosa Pineda by CC 3.0

Brown recluse spiders sometimes find their way into homes by hitching a ride on furniture during house moving, however, staying true to their name, you may not spot them because they like to hide! 90 % of bites from this shy spider do not require medical attention but in case of allergic reactions, it is wise to seek medical attention. 

Unlike many spiders who go in search of live insects to trap and eat, brown recluses save time by eating already dead ones! 

They can also survive for a long time without eating! another reason why you may not see them for months. 

The brown recluse has an unusual pattern on its abdomen which resembles a violin. Some say this is a way to tell the age of this spider as the older they get, the darker these markings will be.

Yellow Sac Spider

Scientific Name: Cheiracanthium inclusum

Yellow Sac Spider
Appears to be a female Yellow sac spider
Credit: Mad Max by CC 3.0

The yellow sac spider is light pale yellow or light yellowish green and an adult female is usually ¼ to ⅜ inches long. 

The male is slimmer and has a wider leg span but both sexes possess eight dark eyes positioned in two rows. 

Their name references the backwardly directed process on the cymbidium of the male palp. This is one of the things which should make the yellow sac spider easier to identify than other spiders. 

It is always a good idea to seek medical advice after a spider bite, however, from a study involving 20 diagnosed yellow sac bites, none were found to produce necrosis.

Brown Widow

Scientific Name: Latrodectus geometricus

Brown Widow
Brown widow spider Latrodectus geometricus backside
Credit: Darklich14 by CC 3.0

The brown widow is the lesser famous cousin of the black widow. They are brown overall with a bulbous abdomen that displays red and tan markings. A bite from this spider may be painful and leave a red mark, although are not fatal. However, there has recently been a report of one bite victim being hospitalized due to the severity of symptoms that manifested.

You may stumble across a brown widow among woody vegetation. Garages, mailboxes, eaves, and dark corners are some locations where this spider may choose to build its web. Their egg sacs have a somewhat spiky appearance.

Brown widow spiders are widely distributed, but are native to South America.

Common house spiders native to Texas

Texas is home to a vast array of common household spiders and they may pay you a visit looking for food sources or shelter.

Known as arachnoids, spiders are air-breathing arthropods with eight legs and two body segments. They use venom to inject their prey through hollow fangs.

Texas has over 900 species distributed evenly throughout the northern and southern parts of the state. 

The following spiders are frequent visitors to basements, garages, and gardens in Texas and will be often seen and easily identifiable to people in this region. 

Cellar Spider

Scientific Name: Pholcidae

Cellar Spider
Daddy-longlegs spider
Credit: David Short by CC 2.0

Often spotted in and around Texas homes, these spiders have a very unique skillset: they vibrate if someone is ill-mannered enough to disturb their webs! Don’t be so quick to denounce these visitors as whilst not poisonous themselves, they will prey upon spiders which actually can be harmful to humans. However, it is always prescient to seek medical advice if bitten by one – the severity of their bites needs more research and has been disputed.

They are delicate-looking yet can stand their ground when it comes to hunting flies, bees, and wasps.

They create their webs in the dark, dingy corners of caves or in piles of leaves and even under rocks.

As far as domestic settings, you may find them if you’re unearthing undisturbed places such as ceiling corners, lofts, and cellars which you guessed it, is how they gained their hence their nickname ‘cellar spider’

Wolf Spider

Scientific Name: Lycosidae

Wolf Spider
Wolf spider
Credit: Bidgee by CC 3.0

These shy spiders are lonesome fellows, living and hunting by themselves. They don’t need much help anyway since they have remarkable eyesight and don’t even spin webs!

The female wolf spider is an attentive mother and attaches its egg sac to the spinnerets at the end of the. After the baby spiders have hatched, she continues to carry them with her for the next few months!

They are only likely to bite if they are being repetitively aggravated and generally only produce pain and swelling which may require ice or antibiotics.

Symptoms of Envenomation 

Spider bites are uncommon as they don’t often bite unless threatened and even then, the bites are usually harmless, but here are some symptoms to look out for if you think you may have been a victim:

Yellow sac spider bite: Yellow sac spider bites are not considered as serious as that of a recluse or widow but may incur a stinging sensation followed by mild swelling. 

A wolf spider bite: A wolf spider bite is not poisonous but you may be allergic to the venom and experience temporary pain, swelling, or itching. 

A widow spider bite: Tremors, nausea, or vomiting may be experienced alone or in combination. You may find that you are perspiring profusely, and have a headache or tremors. You may also have swelling and pain around the bite which can spread to your stomach, chest, and back. This can be accompanied by cramping or abdominal rigidity, often mistaken for appendicitis. 

Recluse spider bites: If you’ve been bitten by a recluse spider, you can expect to feel chills, have a fever, or experience body aches. Look out for red, white, and blue lesions at the bite site and a feeling of restlessness and weakness. The bite may turn into an open sore with skin dying in the surrounding area (necrosis). You may have problems breathing or swallowing – it’s important to seek medical attention if experiencing any of the above symptoms. 

First Aid for Spider Bite Victims

Although rare, spider bites can be fatal, especially if in the mouth or throat. It is important to find out if you have any allergies to prevent anaphylactic shock. 

Many skin abrasions are misdiagnosed as spider bites or turn out to be bites from other bugs such as fleas, ants, mites, mosquitoes, and flies. Even burns have been mistaken for spider bites. 

In the instance that you have correctly diagnosed a spider bite, there is a medical protocol that you should follow: If you are able, raise the area and apply a cold compress or a cloth filled with ice. 

Clean around the wound with mild soap and water – all spider bites should be washed thoroughly to lessen the chances of re-infection. If available, use an antibiotic ointment and if at all possible, catch the spider to identify the species and therefore, the poison. 

Take over-the-counter medication to relieve pain as soon as possible. If the wound is irritated or itching, take an antihistamine containing diphenhydramine or cetirizine. When you can get to a doctor, they may prescribe a muscle relaxant and it is possible that they will administer a tetanus shot.