Daddy long-legs spider

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Daddy long-legs spider
Scientific Classification
Kingdom: Animalia Phylum: Arthropoda Class: Arachnida Order: Araneae Family: Pholcidae
Genera
Pholcus
Image Description

Introduction

The daddy long-leg spider (Pholcidae) is often confused with the "harvestman" (Opiliones) which can also be called a daddy long-leg. The Opiliones is not a true spider, whereas the Pholcidae is. This page is about the Pholcidae.[1]

The Pholcidae is a thin spider that is of silvery color. It has eight very long legs in comparison to it's body, that from one to another create a leg span of around 5cm. It lives almost anywhere in the world, favoring dark, damp climates, but it has been known to live in desert environments as well. There is a myth about the daddy long-leg saying that they are one of the most poisonous spiders in the world, but their fangs are not big enough to bite humans. This is not true at all.[2][3]

Anatomy

Description

The Anatomy of the daddy long-legs is made up of a cephalothorax and an abdomen. They have eight thin, long legs that have sensors that can sense nearby movement, gravitational forces, and stress via their slit organs![4] They have eight eyes called ocelli, and chelicera with small fangs just below them. They have spinnerets that produce silk for making webs located on the end of their abdomen. Their sensors for taste and feel, are located just beside their eyes. Overall, from one leg to the other, they are usually around 5cm long and a silvery color.[5][6]

Reproduction

Description

The male daddy long-leg spider produces sperm in his abdomen. When preparing to reproduce, he puts some sperm in his palpal organs. He then begins to make his move on the female. If the female lets him, then he inserts the semen into the famale's epigyne with his palp. After this the male dies of natural causes, as he is no longer needed for reproduction.[7]

After the eggs become fertilized, the female carries them with her wherever she goes. After the eggs hatch, she takes care of them until she dies. From there, the young spiders eat the mother for nutrition, and then are on their own.[8]

Ecology

Daddy long-legs almost always live indoors. They are often found in cellars or garages, or dark corners of the attic. They can be found almost anywhere around the globe. They like to live in damp habitats, but can even be found in the desert. When scared, they will often begin vibrating back and forth, almost becoming invisible due to their rapid movement.[9][10]

When they make their web, the spin it in such a way that it makes it difficult for the prey to escape, even though it is not necessarily sticky. Also, another main source of food is the red-back spider. The daddy long-legs will often attack other spiders that are in their webs. Sometimes creating a vibrating motion to make the spider think that prey has been trapped in it's web, only to be ambushed by the daddy long-leg.[11][12]

Myths

There is a certain myth that is often associated with the daddy long-leg spider. The myth is basically that they are one of the most poisonous spiders in the world, but their fangs are too short to bite humans. This myth is completely untrue. First, the reader needs to understand that there are two different "daddy long-legs". One is the harvestman (Opiliones) and is often called a daddy long-legs but is not actually a spider, and does not even spin webs and has only two eyes. It is a completely different creature. For the Opiliones the myth is false as it does not have poison or venom glands.[13][14]

The second "daddy long-leg" is the one that the myth really concerns. The Pholcidae is actually a spider that has eight eyes and spins webs. There is no evidence that suggests that they cannot bite. Recluse spiders have the same type of jaw and fangs, and are actually a bit smaller. It would seem that this would mean it is less effective at biting humans, but they are well known for the danger they posses. Also, there are not any reports of Pholcidae causing any where close to a fatal reaction. In further support (or lack thereof) there have been no studies concerning how poisonous they are. So any claim about the daddy long-leg spider being one of the most venomous spiders in the world, has no factual support.[15][16]

References

• [17] Department of Entomology, University of California Riverside.
• Pholcidae (Daddy-long-leg spiders, Cellar spiders) John Murphy, British Arachnological Society.
• FAMILY PHOLCIDAE - Daddy long-leg Spiders Dr. Robert G. Breene and Justin Cordill, Geocities, March 03, 2005.
• The anatomy of a spider Ed Nieuwenhuys, www.xs4all.nl, September 2, 2008.
• Pholcidaewikipedia.org, March 6, 2009.