Long-bodied Cellar Spider, Daddy Long-legs Spider, Skull Spider, Vibrating Spider
Pholcus phalangioides
Pholcidae (Cellar Spiders), Order Araneae. Key characteristics include extremely long, flexible legs and a distinctively shaped, elongated abdomen.
Physical Description
The spider has a small, two-part body consisting of a pale, somewhat flattened cephalothorax and a long, cylindrical, greyish-tan abdomen. The exoskeleton appears somewhat translucent. Its overall appearance is fragile and spindly, with legs many times the length of its body.
Size Estimate
The body length typically ranges from 7 to 9 mm, while the leg span can exceed 50 to 60 mm (approx. 2 inches). Based on the image and typical household scaling, this appears to be an adult specimen.
Coloration & Markings
The body is generally a pale tan, grey, or cream color. The cephalothorax often features a dark, blurry marking on the center that some liken to a human skull, giving it the nickname 'Skull Spider.' The legs characteristically have darkened 'knees' or joints.
Web Type
They build irregular, messy, non-sticky 'tangle webs' or cobwebs. These are typically placed in corners, ceilings, or dark undisturbed areas like basements and garages. The silk is not sticky; instead, it relies on a complex mesh to entangle prey.
Eye Arrangement
They typically have eight eyes arranged in three groups: two lateral groups of three and one central pair of small eyes. The lateral groups are often on slightly raised tubercles.
Leg Characteristics
The legs are exceptionally thin, long, and hair-like. They possess a flexible 'tarsus' allowing them to wrap silk around prey. They often lack the heavy spines found on more robust hunting spiders.
Venom & Safety Information
Venom Information
The venom is not medically significant to humans. While it is effective against their small prey, their fangs (chelicerae) are extremely short and rarely capable of penetrating human skin.
Medical Significance
Harmless. There is an urban legend that they are the most poisonous spiders but their fangs are too small; this is a myth. They are not 'poisonous' and their venom is weak. A bite, while rare, may cause a very mild, short-lived stinging sensation.
Safety Recommendations
No safety measures are required as they are harmless. If their webs become unsightly, they can be gently relocated outside using a jar and card, or simply swept away. They are best left alone to provide free pest control.
Habitat & Behavior
Habitat & Range
Globally distributed due to human trade; they are synanthropic, meaning they live in close association with humans. They prefer dark, damp, or temperate undisturbed indoor spaces like cellars, attics, and crawl spaces.
Behavior & Temperament
They are sedentary ambush hunters. When threatened, they engage in a distinctive 'whirling' or vibrating behavior, spinning rapidly in their web to become a blur to predators. They are very docile and will almost always flee from humans.
Diet & Prey
They eat insects and other spiders. Remarkably, they are known to venture into other spiders' webs to eat them, including much larger species like Wolf Spiders or even Black Widows.
Seasonal Activity
Active year-round in temperature-controlled indoor environments, though they may be more noticeable in the autumn as they move into living spaces in search of stable conditions.
Description
The Long-bodied Cellar Spider is a ubiquitous household resident. Often found hanging upside down in its messy web, it is a master of the indoor ecosystem. Despite its delicate, spindly appearance, it is a formidable predator of other spiders and household pests, making it a beneficial roommate for many homeowners.
Key Features
Extremely long, thin legs; elongated cylindrical abdomen; pale tan coloration; rapid vibrating behavior when disturbed; messy cobweb structure.
Similar Species
Often confused with Harvestmen (Opiliones), which have a single fused body segment and no silk glands. They are also sometimes confused with the Brown Recluse, though the Recluse has much shorter, thicker legs and a different body shape.
Life Cycle
Females carry their egg sacs (containing 20-30 eggs) in their mouthparts (chelicerae) until they hatch, providing a rare form of maternal care. They can live for up to 3 years in stable indoor environments.
Ecological Importance
They provide excellent natural pest control, preying on flies, gnats, mosquitoes, and more 'dangerous' spiders like the Black Widow. They are a vital part of the home's micro-ecosystem.
Conservation Status
Not evaluated by the IUCN; they are abundant and widespread with no known conservation threats.
Interesting Facts
The 'whirling' defense is so effective it makes the spider nearly invisible to birds or wasps. They are also 'araneophagous,' meaning they specialized in hunting other spiders, often using their long legs to stay out of reach of their prey's fangs.
Photography Tips
Focus on the cephalothorax to capture the 'skull' marking. Use a macro lens if possible to show the eyes and the darkened leg joints. They are best photographed against a neutral wall where their thin legs are more visible.
Identified: 2026-07-08T15:57:32.564314