I am fighting a terrible infestation of Tribulus Terrestris (goathead) weeds. On my daily weed patrol, I discovered that several plants were absolutely crawling with tiny black insects. They appeared to be clustering on the underside of the leaves and on the seedpods. I've heard of a species of weevil that feeds on these things. I can't quite tell if the insects I'm seeing match the pictures given there. Is there a chance these could be those beneficial weevils? In which case, I'd be better off leaving those plants alone, so I'd like to know before I dig 'em up.
It is native to interior regions of Italy, France and Rajasthan in India. Microlarinus lareynii feeds on the seeds of the puncturevine, Tribulus terrestris. Together with Microlarinus lypriformis, which feeds on the stems of the puncturevine, it has been introduced as a biological control agent in the United States of America and Canada.
Personally, I'd destroy the weeds myself. The weevils are good, but won't necessarily be as thorough as you will be.