Fangs!

A rainy day, I look around the house for things to look up with the little digital microscope and I find the shrivelled shell of a spider, probably a Tegenaria, in the conservatory, behind a pot. I notice the fangs and look under the microscope. It is not the best photo, but I am quite pleased with the fact that the tiny openings at the end of the fangs (where the venom comes out) are just visible. Click here for a scanning electron photograph of these openings. The fangs act as hypodermic needles, injecting the venom inside the prey's body. The teeth that help hold the prey while the venom is injected are visible at the bottom.

Fearsome stripy jumper

Given the current rainy weather, I was pleasantly surprised to find this male Zebra Spider, Salticus scenicus, on my conservatory wall, inside. Zebra spiders have a bare black body, with white scales and some brown scales on the abdomen. They are warmth-lovers, coming out of their hiding places on clear days, often on walls after they have been heated by the sun. Salticus males have huge chelicerae for their size (a tiny 5 mm!), and they can be seen moving their palps over their black chelicerae as they move about. The chelicerae are opened in a display to rival males, and, if the contest escalates both males will face each other and lock their opened chelicerae together in a sparring match, as shown on this video in Arkive featuring a fight:

A top view of the male Salticus scenicus

Another male showing more brown (photo 20/04/11). The angle allows to see the long fangs folded underneath. Relative to its size, I think they are longer than in Dysdera.

 Despite their tiny size, Salticus make fearsome hunters. A few years back I surprised this male with a fly larger than him.

Male Salticus scenicus with fly (13/05/2009)

Female on 30/04/2011

Do you recognise this female? She is featured in the Bugblog banner. You can see her smaller chelicerae and white palps. Often females have beautifully marked black and white abdomens which give this spider its English name.