Southwest · NM

Spiders of New Mexico

Western black widows are abundant in outbuildings and irrigation infrastructure statewide.

Climate: Arid · Peak activity: March–October

Notable concerns

  • Western black widow
  • Desert recluse

Medically significant species in New Mexico

SpeciesScientificSignificanceRange note
Western Black WidowLatrodectus hesperusMedically significantWestern North America from southern British Columbia south to Mexico, east to the Great Pl
Yellow Sac SpiderCheiracanthium inclusumModerateThroughout the continental United States and southern Canada.

All documented species in this index

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

Seasonal activity in New Mexico

Spider activity in New Mexico follows the documented peak season of March–October. 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 New Mexico 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.
  • 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]NMSU spider identification - NMSU 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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