THE ZEBRA-SPIDER in 3D
by Wim van Egmond
the Netherlands


Click image to view large version. Use red and blue 3D glasses!

One of the commonest spiders you can find around the house is the zebra spider, Salticus scenicus. You can find it sitting on the wall or on a window-frame but it is not so easy to spot. It is a tiny spider with a body size that doesn't exceed 8 millimetres, but you can use a hand lens to its spectacular appearance. The zebra spider belongs to the jumping spiders. It does not make a web but stalks its prey. It will use a silk thread as an anchor. When it spots an insect it will slowly try to approach it. Now and then when it is out of the victim's sight the zebra spider will run. When it is within reach it will jump and paralyse the prey with its venomous 'jaws'.
To be able to capture prey like this jumping spiders rely on superb eye sight. Their eyes are truly remarkable. The front pair is the most impressive. They can be regarded as the best eyes you can find in any arthropod. They work as a telephoto lens. The retina inside the eye can move in 3 dimensions enabling the spider to look in all directions and focus on a subject. When you approach a jumping spider it will position itself so it can observe you. The 6 other eyes are positioned around the head for a 360 degrees vision.
 


Click image to view large version. Use red and blue 3D glasses!

A male zebra spider (left) is hiding its huge chelicerae ('jaws') behind its pedipalps (the little boxing gloves'). The males use the large chelicera for battles. The pedipalps (often called just 'palps') are secondary sexual organs. The spider deposits its sperm on a small web and then uses a special reservoir within the pedipalp to carry its seed around. It will then try to mate with a female zebra spider. Mating is often a dangerous procedure. The male spider uses its front legs to make all kinds of signals to avoid being mistaken for a prey. It has to try to reach the reproductive organ of the female, called the 'epygine', which is situated under the abdomen. When the sperm is transferred the female will carry it in a special compartment and will use it when she is ready to fertilise her eggs.

Since jumping spiders rely so much on their sight they can easily be fooled by using a mirror. The male will try to attack its own reflection.

 

The images were taken from living spiders. These pictures will be part of a CD ROM with 3D images of insects spiders and other small creatures. This CD ROM will be available later this year!

Comments to the author Comments to the author sent via our contacts page quoting page url plus : ('wegmond','')">Wim van Egmond are welcomed.

Many more 3D images can be found via Wim's HOME PAGE 

Microscopy UK Front Page
Micscape Magazine
Article Library

 


Copyright all material: Wim van Egmond

Please report any Web problems or offer general comments to the Micscape Editor,
via the contact on current Micscape Index.

Micscape is the on-line monthly magazine of the Microscopy UK web
site at Microscopy-UK



© Onview.net Ltd, Microscopy-UK, and all contributors 1995 onwards. All rights reserved. Main site is at www.microscopy-uk.org.uk with full mirror at www.microscopy-uk.net.