Southwest · TX

Spiders of Texas

Texas spans multiple climate zones and hosts the widest diversity of medically significant U.S. spiders, including all three primary groups.

Climate: Subtropical to arid · Peak activity: Year-round (south)

Notable concerns

  • Brown recluse
  • Southern/Western black widow
  • Brown widow

Medically significant species in Texas

SpeciesScientificSignificanceRange note
Brown RecluseLoxosceles reclusaMedically significantVerified by Vetter (2008) county-level specimen review. Reports outside this range are almost always misidentifications; an estimated 80% of submitted 'brown recluses' from non-range states are other species.
Southern Black WidowLatrodectus mactansMedically significantSoutheastern United States, from southern New York to Florida, west through Texas and into
Western Black WidowLatrodectus hesperusMedically significantWestern North America from southern British Columbia south to Mexico, east to the Great Pl
Brown WidowLatrodectus geometricusModerateFirst documented in Florida in 1935; major range expansion across the U.S. South began in the 2000s. Continues to displace L. mactans in southern California urban habitats.
Yellow Sac SpiderCheiracanthium inclusumModerateThroughout the continental United States and southern Canada.

All documented species in this index

Species below are present in Texas according to extension publications and the rangeStates records in our species index. Click through for full profiles.

Seasonal activity in Texas

Spider activity in Texas follows the documented peak season of Year-round (south). Indoor sightings often spike in late summer and early fall as males wander to find mates and as cooling outdoor temperatures push synanthropic species toward heated structures.

Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Highlighted months reflect the state extension peak-activity window. Individual species (especially indoor recluse populations) may be active outside this range.

Prevention checklist for Texas homes

  • Seal exterior gaps wider than 1/8 inch around utility penetrations, dryer vents, and weep holes. Install door sweeps on garage and basement entries.
  • Reduce harborage by storing firewood, lumber, and seldom-used boxes off the ground and at least 18 inches from foundation walls.
  • In recluse-active areas, inspect stored clothing, bedding, and shoes before use. Sticky monitor traps placed along baseboards quantify indoor density.
  • For widow-active areas, wear gloves when handling outdoor electrical boxes, irrigation valves, and stacked materials. Widows favor undisturbed voids.
  • Vacuum webs, egg sacs, and spiders rather than spraying. Mechanical removal outperforms most over-the-counter residual sprays for synanthropic species.

If you are bitten

Nearby states in the Southwest region

Sources

  1. [1]Texas A&M spider identification - Texas A&M Cooperative Extension. Accessed 2026-06-14.
  2. [2]Spiders and scorpions submitted as suspected brown recluse - Vetter RS, 2008. Accessed 2026-06-14.

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