Amaurobiidae--hacklemesh weavers? - Callobius

Moved

… Lynette Elliott, 9 March, 2010 - 9:54pm

To id..

To id requires detailed look at the genitalia of the adults--pedipalps of the male, especially the tibia, and epigynum of the female, with males easier to positively id. Unfortunately not all of the dozen or so species known to occur in/near MA have photos on the BugGuide, especially genitalia. There are good palp photos for Amaurobius borealis and ferox and Callobius nomeus. Another species in your area with photos in the BugGuide is Callobius bennetti, but unfortunately no genitalia photos.

The common species here in SE AK is Callobius pictus which has a bite that is painful (like a bee sting) but not dangerous. It also likes to come in/near buildings and often hides in piles of clothes, boxes, etc.

… Susan Wise-Eagle, 9 March, 2010 - 12:18pm

more photos

OK I've loaded a bunch of fresh just-taken photos up here -

http://www.suttonmass.org/animals/spiders/hacklemesh/

I am more than happy to put some of these onto BugGuide for you to use but I figured you'd know best which specific ones are worthwhile for your ID purposes. Just let me know which ones you find useful and I'll add those into this entry.

If none of them are useful, if you could let me know what to try to do better (i.e. what item to focus on and from what angle) I'll do the best I can. We have plenty of these little guys to pose for us.

… Lisa, 9 March, 2010 - 1:51pm

palp photo

Check out this image of Callobius nomeus:
http://bugguide.net/node/view/321289/bgpage
Notice the 3-pronged part on the pedi-palp which is barely visible in this photo. This is the part that is used to id most males in this family. This part is only present on fully adult males. One of the photos you posted looks like an immature male--the palps are large but not as complex as these. If you can get a photo like the one above, it might be possible to id it to species, tho you have a couple of very similar species. Better photos of palp and epigynum are here:
http://bugguide.net/node/view/349081/bgpage
http://bugguide.net/node/view/243925/bgpage
http://bugguide.net/node/view/367499/bgpage
These quality photos are hard to get without a dissecting scope or super macro lens.

… Susan Wise-Eagle, 11 March, 2010 - 1:34am

new camera lens

OK I've just ordered us a better camera lens from Amazon and we'll wait a little while for our little spiders to mature a bit. I'll post better photos once their palps get more complex!

Thank you so much!

… Lisa, 11 March, 2010 - 12:25pm

Amaurobiidae

Looks like one of the Amaurobiidae--hacklemesh weavers. They're very difficult to distinguish by just the markings, even to genus, and definitely not to species, but this looks like one of the Callobius to me.

… Susan Wise-Eagle, 9 March, 2010 - 12:52am

Aha!

We've never had one of these before and we've been spider-watching for several years now! This is really cool!

It does look a lot like this one -

http://bugguide.net/node/view/368340/bgpage

It looks on those pages like some have red legs and others have brown legs. So it isn't that simple, to judge by leg color?

We have a better camera if it would help to take a super close up of the face. As I mentioned we suddenly got 60F weather here in the past few days and then POOF like 8 of them showed up around our front door. I've been having a blast because we've been pretty spider-less all winter!

… Lisa, 9 March, 2010 - 2:24am