Cellar spider (Pholcus species)
Common Name: Daddy Long Legs, granddaddy long-legs spider, daddy long-legs spider, daddy long-legger, cellar spider, vibrating spider.
The Daddy long legs are an introduced spider during the early European colonial period. This species is similar to Pholcus phalangioides but has a shorter almost oval abdomen. Pholcids are web-weaving spiders and are distributed worldwide and were accidentally introduced to New Zealand. They hang inverted in messy, irregular, tangled webs. These webs are constructed in dark and damp recesses, in caves, under rocks and loose bark, abandoned mammal burrows in undisturbed areas in buildings and cellars, hence the common name "cellar spiders". However, Pholcids are also quite commonly found in warm, dry places, such as household windows.
When a victim is trapped in the web it immobilises it by wrapping it in silk, not like other spiders that use venom.
There is an often-repeated urban myth that states ‘the daddy longlegs is the most poisonous spider in the world, but it can’t bite you because its fangs are too small’. The myth is incorrect at least in making claims that have no basis in known facts. There is no reference to any pholcid spider biting a human and causing any detrimental reaction. If these spiders were indeed deadly poisonous but couldn't bite humans, then the only way we would know that they are poisonous is by milking them and injecting the venom into humans.
Cellar spider versus whitetail spider.
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