Lace Webbed Spider
Special features: This is one of two very similar species of spider - hence the name similis. If you find one in a house it is likely to be Amaurobius similis. If you find one in a garden or outdoors it is likely to be Amaurobius fenestralis
When the species was first described the name "fenestralis", meaning 'of windows', was given to the species as it was thought to be associated with houses. However, it was later found that there were two different species. The one which initially been described was in fact the species which usually occurs outside under bark on trees. The house-associated species was therefore given the name similis ('similar'). Fenestralis is usually brighter and more clearly marked but to be certain of identification the genitalia need to be checked.
These spiders produce a blueish coloured silk around the entrance to holes and crevices on just about every wall you look at. If you go out after dark with a torch you can often see the spiders out in the open.
Latin name: Amaurobius similis
Size: Body length up to 10mms.
Distribution: Found in most parts of the UK.
Months seen: All year round
Food: Small insects.
Habitat: Holes in walls and fences. Sometimes around window frames.