Broad-faced Sac Spider

Scientific Name: Trachelas tranquillus

Order & Family: Araneae; Trachelidae

Size: 7 to 10 mm (females); 5 to 6 mm (males)

Broad-faced Sac Spider

Natural Habitat

Found outdoors under leaf litter, rocks, or logs; commonly enters homes in the fall to find a warm place to overwinter.

Diet & Feeding

Carnivorous; feeds on other spiders and dead or dying insects.

Behavior Patterns

Night-active hunters that do not build webs for prey capture; instead, they build silken retreats for resting and overwintering.

Risks & Benefits

Provides natural pest control by eating other insects. While their bite can be painful and cause mild localized swelling, they are generally not dangerous to humans unless a secondary infection occurs.

Identified on: 6/23/2026