Can anyone identify this type of spider that was found in my dad's house in Surrey?
The photo's not the best but to my untrained eye it looks potentially like a False Widow. Someone in our household was bitten by the spider on the left while they were sleeping which was described as "...feeling like a bee sting..." and has had to take antibiotics to counter a subsequent infection. The spider on the right is more intact because it was not as manhandled as the one that bit...
The "more intact" spider looks like a false widow (Steatoda nobilis).
The biter? Potentially also...but, better pics would help in a firmer ID.
There are a few male Steatodas around at the moment, these wander about & are more likely to find their way into trouble with people. Females are typically at home in their webs & don't like to stray from them. There are always exceptions, of course...
Both spiders were found in the bedroom, the second intact spider only after a "little fumigation".
I had a thorough look for webs but didn't find anything but given my dad stays in that bedroom and is infirm I will take a closer look.
Where do Steatodas prefer to create webs? If outside - as I assume - are they more likely to move indoors for the warmth as autumn or winter take hold? Or will they most likely stay outside for food/mates?
They occasionally like to make indoor webs high up, around window frames/sills/cracks/recesses, conservatories are popular.
Outside (more common): porches, window frames again, under sills, cracks in exterior walls, outbuildings etc. Female's webs can be "hammock" like, if they live in them for a good while they can be quite expansive, as they add to them bit by bit. They seem as much a defensive structure as anything else, large disturbances in the web often send them scuttling for safety. They're not very brave, or aggressive (towards us), funnily enough.
Males wander about more, don't build such elaborate webs from what I have seen, but can also hang out in a female's web from time to time.
The females tend to stick to their web, wherever it is made, they withdraw into their hiding place over the winter & will probably re-emerge in spring if just a year, or two, old. They don't need to come inside. Males stop feeding when mature and don't live as long, perhaps a year?
I now have 2 (maybe 3 depending on whether I can identify a small male who has recently turned up?) living in my front room, inside the window frame, a mature female & a spiderling about a meter away. They tend to stay put, though I suspect the spiderling will look for better cover as it grows and becomes more conspicuous. The females, once established in a web, don't concern me. Though I tend to relocate wandering males when I see them.
The bite sounds unpleasant, however they are very well established where I live (along with other false widow species & even less desirable spiders), despite that bites are very rare. There's no avoiding them really...like bees & wasps?