Cellar Spider, Daddy Long-Legs Spider, Skull Spider
Pholcus phalangioides
Pholcidae (Cellar Spiders), Order Araneae. Key family characteristics include extremely long, delicate legs and an oval or elongated abdomen.
Physical Description
The spider has an extremely delicate body structure with very long, slender legs. The cephalothorax is pale and somewhat rounded, while the abdomen is elongated, cylindrical, or slightly oval in shape, often giving it a fragile appearance.
Size Estimate
Body length is typically around 7 to 10 millimeters, with a leg span reaching up to 5 to 7 centimeters.
Coloration & Markings
Pale gray, tan, or yellowish-brown overall, sometimes featuring darker markings on the cephalothorax that can resemble the shape of a skull.
Web Type
Irregular, tangled cobwebs built in corners, ceilings, cellars, and dark, undisturbed spaces.
Eye Arrangement
Eight eyes arranged in a distinct cluster: a compact group of three triads and a small pair of median eyes, characteristic of the Pholcidae family.
Leg Characteristics
Extremely long, thin, and fragile legs with slight banding. When disturbed, the spider characteristically vibrates or bounces rapidly in its web to blur its image.
Venom & Safety Information
Venom Information
Neurotoxic venom tailored for small invertebrate prey. Extremely weak relative to humans and rarely capable of piercing human skin.
Medical Significance
Harmless to humans. Despite urban myths about extreme toxicity, they pose zero medical threat and cannot deliver a medically significant bite to humans.
Safety Recommendations
No safety measures needed as they are completely harmless. If unwanted, they can be gently relocated using a cup and a piece of paper.
Habitat & Behavior
Habitat & Range
Cosmopolitan distribution worldwide. Highly adapted to human dwellings, basements, cellars, garages, and dark corners, as well as caves and under rock ledges outdoors.
Behavior & Temperament
Docile and non-aggressive. When threatened, instead of fleeing, it performs a rapid vibrating motion to become virtually invisible to predators.
Diet & Prey
Insects and other spiders, notably known for subduing and eating larger spiders, including venomous species like widow spiders.
Seasonal Activity
Active year-round indoors, as they thrive in climate-controlled buildings, with peak reproduction occurring during warmer months.
Description
The cellar spider is a ubiquitous household companion, easily recognized by its exceptionally long legs and fragile body. Hanging upside down in messy webs, these gentle arachnids are harmless pest controllers that quietly manage populations of flying insects and other spiders.
Key Features
Extremely long, spindly legs, elongated pale abdomen, habit of vibrating rapidly when disturbed, and preference for corners of ceilings and cellars.
Similar Species
Opiliones (Harvestmen, also commonly called daddy long-legs), which are not true spiders, lack silk glands, and have a fused body oval. Also confused with cellar-dwelling spitting spiders (Scytodidae).
Life Cycle
Females carry eggs in a loose silk cluster held in their jaws. Spiderlings hatch and molt multiple times, with adults living for several years.
Ecological Importance
Acts as an effective natural pest controller in homes and buildings, helping to suppress populations of mosquitoes, flies, and other nuisance insects.
Conservation Status
Not evaluated by the IUCN, but highly secure and widespread globally due to close association with human habitations.
Interesting Facts
Despite the urban legend that they are the most venomous spiders with mouths too small to bite humans, scientific testing has shown their venom is quite weak to vertebrates and poses no danger.
Photography Tips
Use macro lenses with soft, diffused lighting to capture the fine leg details and subtle markings on the cephalothorax. Photograph against a neutral background for clarity.
Identified: 2026-07-29T13:48:16.241173