Dysdera help

sebastianbawn · #1 (**permalink**) 21-05-2009, 05:56 PM

I found this gal in bristol in a front garden. I have checked the species and as far as I can see it is missing the dorsal spines on femur IV. Therefore I deduced it was D.erythrina but I would like an experts view please

sebastianbawn · #2 (**permalink**) 23-05-2009, 12:38 PM

Having seen another thread I have found that you cannot take he dorsal spines as gospel. Given the BAS data, habitat seems wrong for Dysdera erythrina so more likely crocuta. Does anyone have any knowledge of these guys?

Geoff F · #3 (**permalink**) 23-05-2009, 06:56 PM

According to my book. A Bristol garden is a suitable habitat for both species.

One of the chief differences between the 2 species is size, but obviously easier to seperate like this if you have both species side by side. Anyhow, D. erythrina is listed as upto 10mm for a female against 15mm for D. crocota.

D. crocota should have between 1 and 3 spines of femur IV but beware of misidentification with Harpactea which also have at least 3 spines here, but are generally different in colouration.

Now I will put the book down and make way for someone who has all this information in their head.

No.9 Spider · #4 (**permalink**) 24-05-2009, 10:22 PM

Can't see both relevant leg sections, but if you're happy the spines are absent (and no signs of there having been any, as they sometimes get damaged) then It should be D. erythrina.
Harpactea hombergii is comparatively, a very slight looking spider, distinctly different in appearance, and extremely fast as well!

No.9 Spider

sebastianbawn · #5 (**permalink**) 24-05-2009, 10:32 PM

Have a pic of Harpactea hombergii and it is very different. I thought at first this was D.crocuta as that is the most common. But the dorsal spines... Shame you cant rely on them as this would have been an easier ID. I want to go with D.erythina but I still have my doubts!