Texas records
Eastern Black-tailed Rattlesnake in Texas
VenomousCrotalus ornatus

Yes. The Eastern Black-tailed Rattlesnake has been recorded in 31 Texas counties. It is venomous. Heavy body, broad triangular head, vertical (cat-like) pupils, and a segmented keratin rattle at the tail tip.
If you are bitten
Rattlesnake bites are medically serious. Expect intense pain, rapid swelling, and bruising. Stay calm, keep the bitten limb still and roughly level with the heart, remove rings and tight clothing, and get to an emergency room immediately. Do NOT apply a tourniquet, cut the wound, apply ice, or try to suck out venom. Call Poison Control at 1-800-222-1222 or 911 in the US, or your local emergency number. (Source: CDC.)
Texas counties with Eastern Black-tailed Rattlesnake records
31 listedSee the full Eastern Black-tailed Rattlesnake profile or all snakes in Texas.