Long-bodied Cellar Spider, Daddy Long-legs
Pholcus phalangioides
Pholcidae (Cellar Spiders), Order Araneae. Key family characteristics include extremely long, delicate legs and an oval or fused cephalothorax and abdomen.
Physical Description
The spider has a small, oval-shaped body with a fused cephalothorax and a distinctly elongated, cylindrical abdomen. Its texture appears smooth, and its most prominent feature is its exceptionally long, thread-like legs relative to its tiny body size.
Size Estimate
Body length is approximately 7 to 10 millimeters, with a massive leg span stretching up to 5 to 7 centimeters. This specimen appears to be an adult.
Coloration & Markings
Pale grayish-brown, beige, or translucent yellow overall. The cephalothorax often features a darker central marking, and the abdomen may display subtle, pale mottled patterns.
Web Type
Irregular, loose 3D tangle web (cobweb) constructed in corners, ceilings, basements, or window frames. These webs are non-sticky and trap prey through a complex spatial maze.
Eye Arrangement
Eight eyes arranged in a unique triad formation: two groups of three side-eyes and a pair of smaller median eyes situated on a raised tubercle.
Leg Characteristics
Extremely long, thin, and fragile legs with flexible joints. When disturbed, the spider employs a signature defensive vibration, blurring its body rapidly in the web.
Venom & Safety Information
Venom Information
Mild venom adapted specifically for subduing small insect prey. It possesses very weak toxicity toward humans and large mammals.
Medical Significance
Harmless to humans. Its fangs are generally too short or weak to pierce human skin, and even if a rare puncture occurs, the effect is negligible, typically causing only minor local irritation.
Safety Recommendations
No safety measures are necessary as these spiders pose zero threat to humans. If desired, they can be gently relocated outside using a cup and a piece of paper.
Habitat & Behavior
Habitat & Range
Cosmopolitan distribution found globally in temperate and tropical regions. Prefers dark, humid human habitations such as cellars, basements, garages, corners of rooms, and window screens.
Behavior & Temperament
Docile, sedentary, and completely non-aggressive. When threatened, it vigorously bounces or vibrates in its web to evade potential predators by becoming a blur.
Diet & Prey
Insects and other spiders, including medically significant species like the redback or hobo spider. It uses its long legs to wrap prey in silk from a safe distance before biting.
Seasonal Activity
Active year-round indoors where climate control provides stable temperatures, though mating and increased wandering may peak during warmer months.
Description
Commonly known as the daddy long-legs, Pholcus phalangioides is a familiar household companion found globally. Despite urban legends regarding its supposed extreme toxicity, it is entirely harmless and beneficial, silently consuming household pests and even other more dangerous spiders.
Key Features
Extremely long and spindly legs, tiny elongated cylindrical abdomen, pale coloration, and the characteristic frantic vibrating response when disturbed.
Similar Species
Harvestmen (Opiliones, which are arachnids but not true spiders, possessing a single fused body segment and no silk glands) and cellar spiders of other genera like Holocnemus.
Life Cycle
Females carry eggs in a loose silk cluster held in their chelicerae until hatching. Spiderlings emerge as miniature adults and undergo several molts. Lifespan can extend up to three years.
Ecological Importance
Acts as an effective natural pest control agent inside buildings, helping to keep populations of flies, mosquitoes, and other household insects in check.
Conservation Status
Not evaluated by the IUCN, but populations are secure, abundant, and thriving globally alongside human habitations.
Interesting Facts
Cellar spiders are notorious for hunting and consuming other spiders, including larger funnel-web and widow spiders, utilizing their long reach to keep dangerous prey at a distance.
Photography Tips
Use macro lenses with adequate lighting to capture the delicate leg structure and eye arrangement. Photographing against a contrasting background helps highlight the translucent body details.
User Notes
Identified: 2026-09-16T23:12:36.095406