Cellar Spider, Daddy Long-Legs Spider
Pholcus phalangioides
Pholcidae (Cellar Spiders), Order Araneae
Physical Description
Small, oval-shaped abdomen that is considerably longer than it is wide, paired with an exceptionally small, rounded cephalothorax. The legs are remarkably long and delicate, often called spindly.
Size Estimate
Body length ranges from 7 to 10 millimeters, with an expansive leg span reaching up to 5 to 7 centimeters.
Coloration & Markings
Pale gray, yellowish-tan, or whitish coloration with subtle darker markings or spots on the cephalothorax and abdomen.
Web Type
Irregular, sticky tangle webs (cobwebs) typically constructed in dark, undisturbed corners, cellars, and basements.
Eye Arrangement
Eight eyes arranged in two lateral triads and a pair of smaller median eyes closely grouped on an elevated tubercle.
Leg Characteristics
Extremely long, thin, and fragile legs lacking heavy spination, known for performing rapid, blurry vibrating motions when disturbed.
Venom & Safety Information
Venom Information
Envenomation is rarely able to pierce human skin; venom is mild and poses no medical threat to humans despite urban legends.
Medical Significance
Not medically significant. They possess tiny chelicerae that typically cannot puncture human skin, and their venom is exceptionally weak against mammals.
Safety Recommendations
No safety measures needed as they are completely harmless; if removal is desired, gently capture with a cup and slide a piece of paper underneath to release outside.
Habitat & Behavior
Habitat & Range
Cosmopolitan distribution worldwide; highly synanthropic, predominantly found indoors in dark, humid areas like cellars, basements, and crawl spaces.
Behavior & Temperament
Docile and completely harmless to humans. When threatened, they rapidly vibrate their bodies in their webs to blur their image and evade predators.
Diet & Prey
Generalist insectivores that readily consume crawling and flying insects, and notably hunt and consume other spiders, including venomous species like widows.
Seasonal Activity
Active year-round indoors where climate is controlled, though reproduction and mobility often peak during warmer spring and summer months.
Description
The cellar spider is a familiar household guest characterized by its tiny body and extraordinarily long, thread-like legs. Often mistaken for harvestmen, these web-building spiders are harmless pest controllers that quietly maintain corners of basements and garages.
Key Features
Extremely long, spindly legs relative to a tiny, elongated pale body, combined with the signature defensive behavior of vibrating rapidly within an irregular cobweb.
Similar Species
Opiliones (Harvestmen, which are not true spiders and lack silk glands and constricted waists) and cellar spiders of other genera like Holocus.
Life Cycle
Females carry eggs in a loose silk cluster held directly in their jaws until hatching. Spiderlings undergo multiple molts to reach maturity, with adults living for several years.
Ecological Importance
Serves as an effective natural pest control agent inside buildings by preying on nuisance insects and controlling populations of other spiders.
Conservation Status
Not evaluated by the IUCN, but extremely abundant, widespread, and thriving globally alongside human habitations.
Interesting Facts
Despite the urban legend claiming they are the most venomous spiders with mouths too small to bite humans, scientific studies have thoroughly debunked this myth; their venom is quite weak.
Photography Tips
Use a macro lens with good side lighting to highlight the delicate leg structure and tiny cephalothorax details against a neutral background.
Identified: 2026-09-07T17:49:45.302036