Long-bodied Cellar Spider, Daddy Long-legs, Skull Spider
Pholcus phalangioides
Pholcidae (Cellar Spiders), Order Araneae. Characterized by extremely long, thin legs and hanging inverted in messy webs.
Physical Description
The spider has a small, elongated cylindrical abdomen and a circular cephalothorax. The body is thin and somewhat translucent with a pale, grayish-tan texture. Female abdomens are often significantly more robust than males.
Size Estimate
Body length 7–9 mm; leg span can reach up to 50 mm. The specimen in the image appears to be an adult.
Coloration & Markings
Pale tan, beige, or greyish with a darker, skull-like or fiddle-shaped mark on the cephalothorax. The abdomen is typically monochromatic pale grey or tan.
Web Type
Tangle/Cobweb. It builds irregular, messy, non-sticky sheets in corners of ceilings, basements, and shaded areas. Unlike orb weavers, their silk is not sticky; they rely on the complexity of the silk maze.
Eye Arrangement
8 eyes in total. Six eyes are arranged in two lateral triads of three, with two smaller eyes located in the anterior median position.
Leg Characteristics
Extremely long, delicate, and hair-like. They feature flexible tarsi (end of legs). They lack notable spines but have a very smooth, glass-thread appearance.
Venom & Safety Information
Venom Information
Neurotoxic to insects, but extremely weak. There is an urban legend that they are the 'most venomous spider but their fangs are too small'—this is a myth. Their venom is not dangerous to humans.
Medical Significance
Harmless. Bites are extremely rare because their fangs are tiny and they are not inclined to bite humans. If a bite occurs, it typically results in a mild, short-lived stinging sensation.
Safety Recommendations
No safety measures are required as they are harmless. If relocation is desired, they can be easily moved using a cup and a piece of paper. They should be left alone to provide free pest control.
Habitat & Behavior
Habitat & Range
Cosmopolitan distribution; found worldwide. Highly synanthropic, preferring human structures like basements, garages, attics, and caves where temperatures are stable.
Behavior & Temperament
Very passive and non-aggressive. When threatened, they exhibit a 'whirling' or 'vibrating' behavior, spinning rapidly in their web to blur their form and confuse predators.
Diet & Prey
Generalist predators consuming flies, mosquitoes, and ants. They are famous for being 'spider-killers,' successfully hunting larger and more venomous spiders like Black Widows or Hobo spiders.
Seasonal Activity
Active year-round in temperature-controlled indoor environments. In unheated areas, they are most visible during summer and autumn.
Description
A delicate, spindly resident of homes around the world, the Cellar Spider is a master of the dark corner. Though fragile in appearance, it is a formidable predator of other household pests. It is often welcomed by homeowners as a natural pest control agent.
Key Features
Extremely long legs, cylindrical abdomen, vibrating defense behavior, and the tendency to hang upside down in high corners.
Similar Species
Harvestmen (Opiliones) which have a single body segment and no silk; Crane Flies (Tipulidae) which are flying insects; and Physocyclus species.
Life Cycle
Females carry their egg sacs in their chelicerae (mouthparts) rather than attaching them to the web. After hatching, spiderlings remain near the mother for a short time. They can live up to 3 years.
Ecological Importance
Crucial for indoor pest management. They act as apex predators within the micro-ecosystem of a household, keeping populations of flies and more dangerous spiders in check.
Conservation Status
Not evaluated by IUCN, but populations are stable and widespread globally due to association with human habitation.
Interesting Facts
The 'vibrating' defense can reach speeds that make the spider nearly invisible to the human eye. They are also known to invade other spiders' webs and vibrate the silk to mimic trapped prey before attacking.
Photography Tips
Focus on the cephalothorax to capture the eye arrangement. Use a macro lens if possible. Since they are often in dark corners, a soft flash or side-lighting is necessary to highlight the delicate legs.
Identified: 2026-06-22T04:37:52.394473