Cobweb Spiders
What are they?
A group of reclusive spiders that generally like to hide away in dark, sheltered corners in woodland or in basements and out buildings. They make rather messy, tangled webs which are made up of a confusing tangle of single strands, rather than a flat sheet. Most species are rather small spiders with relatively small, rounded abdomens. Despite being reclusive, several are well-known, as this group contains the common house spider and the black widows.
Identification
The handful of species that we have in our area can readily be identified by the overall color and the markings on the abdomen. This family includes the black widow spiders; notorious for their venomous bite, these are small, retiring spiders that are extremely unlikely to bite unless provoked. There is always the outside chance of accidentally coming across one while gardening and the best prevention against bite is to always wear thick gardening gloves and to take care when working in shady corners.
Common House Spider Parasteatoda tepidariorum
One of our commonest spiders, which must surely be present in every building in the area! The poorly-constructed, three-dimensional tangle of threads can be extensive and fill large areas of basements. They typically hold a number of the distinctive, papery wrappers that surround the egg clusters.
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Southern Black Widow Latrodectus mactans
Very similar to the Northern Black Widow and best told from it by the pattern of the hour glass on the underside of the abdomen. In the Southern Black Widow, the two red triangles on the underside of the abdomen to form an the hour glass pattern. This species is also more likely to have other red or white marks on the abdomen, especially in younger females. Anecdotally, this species is said to be more agressive and more likely to bite than the northern species.
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Northern Black Widow Latrodectus variolus
Very similar to the Southern Black Widow and best told from it by the pattern of the hour glass on the underside of the abdomen. In the Northern Black Widow, the two halves of the hour glass do not touch, thus it shows two red triangles with points aimed toward each other. This species is also less likely to have other red or white marks on the abdomen. Anecdotally, this species is said to be far less likely to bite than the southern species.
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