Sac Spider (likely Broad-faced Sac Spider)
Scientific Name: Clubionidae (family), possibly Trachelas tranquillus (Broad-faced Sac Spider)
Order & Family: Araneae (Order), Clubionidae (Family)
Size: Typically 3-15 mm (0.12-0.6 inches) in body length, depending on species.
Natural Habitat
Sac spiders are commonly found outdoors under bark, stones, and leaf litter. Indoors, they can be found in corners, cracks, and behind objects, often building silken retreats (sacs) rather than elaborate webs.
Diet & Feeding
Predatory, feeding on various small insects and other arthropods. They are active hunters, especially at night.
Behavior Patterns
Nocturnal hunters, they do not build webs for prey capture but rather for shelter (retreat sacs). They are agile and quick movers. When disturbed, they may bite as a defense mechanism. They are solitary creatures.
Risks & Benefits
Potential Risks: Their bite can be painful, similar to a bee sting, and may cause localized swelling, redness, and itching, sometimes with a small lesion. While generally not medically significant, some individuals might react more strongly. Potential Benefits: They help control populations of other pest insects in and around homes.
Identified on: 11/6/2025