Steatoda nobilis or grossa?

Keg · #1 (**permalink**) 09-09-2010, 02:46 PM

Hi,
Recently become what can only be described as slightly obsessed with Identifying spiders, have got a copy of Collins Field Guide Spiders of Britain and Northern Europe, and think this is a male S. Nobilis but would like the opinion of someone who knows more. Was found on the outside wall of my house in Cornwall, and I have a small dog, so was considering relocating any I find to be on the safe side.

No.9 Spider · #2 (**permalink**) 09-09-2010, 02:55 PM

Yes looks good for a male Steatoda nobilis. Shouldn't be a problem to your dog.

No.9 Spider

John_M · #3 (**permalink**) 09-09-2010, 06:43 PM

I have oodles of these beasties around the house and garden. We have 4 cats and 2 rabbits, and have never had a problem; if the spiders are disturbed, they scarper to safety. I should think your dog is safe.

Keg · #4 (**permalink**) 09-09-2010, 11:54 PM

Thanks for the info. Will just leave them be when I see them. What is the best way of distinguishing nobilis from grossa by eye?

John_M · #5 (**permalink**) 10-09-2010, 06:03 AM

Steatoda nobilis has a quite distinctive rectangular pattern on the abdomen,

and are usually dark brown / black in colour.
S.grossa is often a sort of purplish brown, and the abdominal pattern is more 'spotty', and often quite indistinct.