Cellar Spider, Daddy Long-Legs
Pholcus phalangioides
Pholcidae (Cellar Spiders), Order Araneae. Key family characteristics include long, delicate legs and an oval or elongated abdomen.
Physical Description
The spider features an extremely small, oval-shaped abdomen and a small, fused cephalothorax. The overall build is remarkably delicate with exceptionally thin, thread-like proportions.
Size Estimate
Body length is approximately 7 to 10 millimeters, with a total leg span reaching up to 5 centimeters. This appears to be an adult specimen.
Coloration & Markings
Pale, translucent greyish-yellow to light brown, sometimes featuring faint darker markings on the carapace and abdomen.
Web Type
Irregular, messy 3D tangle webs or cobwebs constructed in dark, damp corners, basements, and near the ground.
Eye Arrangement
Typically possess eight eyes arranged in a triad on each side and a pair of smaller median eyes, though sometimes reduced to six.
Leg Characteristics
Extremely long, thin, and fragile legs lacking strong spines, often held in a flattened, sprawling posture. They can easily detach a leg if grabbed.
Venom & Safety Information
Venom Information
Neurotoxic venom tailored specifically for small arthropods. Completely harmless to humans, though urban legends falsely claim they are lethally venomous.
Medical Significance
Not medically significant. Their chelicerae are generally too weak to pierce human skin, and envenomation poses no threat to humans.
Safety Recommendations
No safety measures are necessary as they are completely harmless. If relocation is desired, simply use a container and a piece of paper to gently move them outside.
Habitat & Behavior
Habitat & Range
Cosmopolitan distribution worldwide. Highly synanthropic, predominantly found indoors in dark, humid environments such as cellars, garages, bathrooms, and crawlspaces.
Behavior & Temperament
Docile and non-aggressive. When disturbed, they perform a rapid, blurry vibrating or bouncing motion in their web to confuse potential predators.
Diet & Prey
Insects and other spiders, including medically significant species like widow spiders. They use their long legs to wrap prey from a safe distance before envenomating.
Seasonal Activity
Active year-round indoors, as they benefit from climate-controlled human structures where temperatures remain stable.
Description
Commonly encountered in homes worldwide, the cellar spider is an unassuming yet exceptionally beneficial houseguest. Recognized by its tiny body and extraordinarily long legs, it haunts the dark corners of basements and sinks, silently keeping pest populations in check.
Key Features
Extremely long and delicate legs, tiny oval abdomen, pale translucent coloration, and the characteristic vibrating defense mechanism when disturbed.
Similar Species
Opiliones (harvestmen, which are not true spiders and lack a divided body) and Phalangium opilio. Distinguished by the spider's clearly divided two-part body and silk-producing abilities.
Life Cycle
Females carry eggs in a loose, silk-bound cluster held in their chelicerae. Spiderlings hatch as miniature adults and undergo several molts. Lifespan can extend up to several years.
Ecological Importance
Serves as an effective natural pest controller in human habitations, consuming flies, mosquitoes, and even other potentially harmful spiders.
Conservation Status
Not evaluated by the IUCN, but populations are extremely secure, widespread, and thriving globally alongside human habitations.
Interesting Facts
Despite the persistent urban legend that they possess the world's most potent venom, scientific studies have proven their venom is very weak against vertebrates and poses zero danger to humans.
Photography Tips
Use macro lenses with a steady hand or tripod. Capture from a top-down or slight side angle to highlight the delicate leg structure and body proportions against a neutral background.
Identified: 2026-10-03T04:58:10.502158