What function do the sigilla serve?

[Kenny carson]

Hi
I am curious to know the use of the sigilla found at the base of the coxae. Do they serve as glands? I have witnissed several of my tatantulas with a leg tucked under their Bodies touching their sternum area with their claw or telotarsus? Maybe just a coincidence. Are they used during mating? If they where muscle attachment points they would surely be inverted?
I have no idea and I cant find it in any of my books. Any info would be most appretiated.

[Colin D Wilson]

Sigilla

As far as i've always been aware, the sigilla are just noticable external muscle attatchment points on the sternum and they don't play an active part in mating. If anyone knows differently, then i'm up for a spell of learning as well.