id spider with stabilimentum please

Rambling Rob · #1 (**permalink**) 01-07-2009, 10:37 PM

Hiya folks,

Is it possible to id this spider? The body was around 0.5cm long, or slightly more, greenish hue. Legs stripey. It had just caught a grasshopper in its web which has a stabilimentum, I think (tho I'm not clear what that is/ what it does).

Sorry the pics are fuzzy. Taken last evening after sunset down among the Spiny Restharrow at Whitecliff Bay, IoW, on a rather steep slope.

Thanks for looking, Rob

With wriggling prey..

..dorsal view..

..ventral view..

Venger · #2 (**permalink**) 01-07-2009, 11:01 PM

Looks like a juvenile Argiope bruennichi
There are many theories about stabilimentums:
Camouflage
Moulting platform
Web warning (so birds don't fly through it)

or all of the above!

Juveniles build webs with more stabilimentum than adults (usually)

Rambling Rob · #3 (**permalink**) 01-07-2009, 11:16 PM

Thanks Venger - I've seen a few of the adults of that species about the IoW (though not yet this year), looking far more impressive than this; I hadn't considered a juvenile spider. Last time I saw one at Newtown it was repeatedly springing in and out on its web which looked quite alarming close up.

Rob