Theridiidae female on grape leaf - Cryptachaea porteri

Identified using the epigynum

Identified using the epigynum. This species is common in some grape vineyards late in the growing season. Levi says not all individuals have the sharp hump, but all that I have seen have it.

Until 2008 this was Achaearanea porteri.

… Devin Carroll, 7 October, 2010 - 10:10pm

Moved

Moved from Achaearanea.

… Devin Carroll, 7 October, 2010 - 10:07pm

Moved

Moved from Cobweb Spiders.

… Devin Carroll, 21 October, 2009 - 2:33pm

Moved

Moved from Theridion melanurum.

… Devin Carroll, 21 October, 2009 - 1:06pm

Moved

Moved from Cobweb Spiders.

… Devin Carroll, 20 October, 2009 - 9:06pm

Hi Devin

At this time we don't believe this is Theridion melanurum. We are looking into other possibilities. See discussion here.

… Lynette Elliott, 20 October, 2009 - 9:12pm

unlinked

This spider was previously linked to 238502, but they aren't the same spider, so I've unlinked them and moved these back out to the family page.

… Lynette Elliott, 10 October, 2009 - 10:54am

Same spider

Lynette,

These are the same spider. I have the notes. I admit the photography makes them look different. The species is T. melanurum.

I took this picture because this specimen is unusually dark.

… Devin Carroll, 20 October, 2009 - 9:10pm

Weird

The first spider has a light colored mark up the center of the abdomen and the second/third have a dark mark up the center. They sure look different to me?

… Lynette Elliott, 20 October, 2009 - 9:14pm

dorsum and sternum

502 is the underside. The others are the top.

… Devin Carroll, 20 October, 2009 - 10:47pm

Ah ha!

I see what you were thinking. However, I don't think that 502 is the uderside of a spider. It clearly looks like a dorsal shot to me. I can see reflection off the eyes, I can see the legs folding up into the air, and that is the dorsal pattern of Theridion melanurum. I took the liberty of rotating your image which helps to show the 'knees' clearly pointing up into the air...

… Lynette Elliott, 21 October, 2009 - 9:34am

My bad.

Lynette, you are correct. Thanks for being persistent.

I looked at the specimen and it appears to be Achaearanea. It does not exactly fit any species known from California. The epigynum looks like A. porteri or perhaps A. tepidariorum, but Levi's descriptions of those spiders do not mention the tubercle on the abdomen.

It is definitely not A. rupicola.

… Devin Carroll, 21 October, 2009 - 1:08pm

Moved

Moved from Theridion melanurum.

… Lynette Elliott, 10 October, 2009 - 10:52am