Sac Spider (possibly Broad-faced Sac Spider, Trachelas tranquillus)
Scientific Name: Trachelas tranquillus (or a closely related species within Clubionidae)
Order & Family: Order Araneae, Family Clubionidae (less commonly Cheiracanthiidae, depending on species)
Size: Typically 3-10 mm for body length, with legs extending their overall size.
Natural Habitat
Sac spiders are commonly found in and around human dwellings, including indoors and in gardens. They can be found under bark, stones, or leaves, and often create silken retreats (sacs) in rolled leaves or other sheltered spots.
Diet & Feeding
Primarily carnivorous, feeding on a wide variety of small insects and other arthropods. They are ambush predators and active hunters.
Behavior Patterns
Fast-moving hunters that do not build webs for prey capture. They actively stalk their prey. They are generally solitary. Many species are nocturnal, hunting at night.
Risks & Benefits
Potential Risks: Their bite can be painful and may cause localized reactions such as redness, swelling, and itching, similar to a bee sting. While generally not medically significant, some individuals might experience more pronounced symptoms. Potential Benefits: They help control populations of various insect pests in and around homes and gardens.
Identified on: 8/20/2025