Broad-faced Sac Spider

Scientific Name: Trachelas tranquillus

Order & Family: Araneae, Corinnidae

Size: Females 7-10 mm; Males 5-8 mm

Broad-faced Sac Spider

Natural Habitat

Typically found outdoors under bark, stones, and leaf litter, but often enters homes and other buildings, especially in cooler weather.

Diet & Feeding

Predatory, feeding on various small insects and other arthropods.

Behavior Patterns

Nocturnal hunters, they do not build webs for catching prey, but rather actively stalk and subdue their victims. They spin silken sacs or tubes for resting and egg-laying.

Risks & Benefits

Their bite is considered medically significant, though not typically severe. Bites are often painful, causing localized redness, swelling, and itching, and can sometimes lead to a small lesion or blister. They are generally beneficial as predators of other insects. They pose a mild risk to humans due to their defensive bite when threatened.

Identified on: 11/12/2025