Tribulus.
Pliny, Naturalis Historia 21.54: Tribulo proprietas, quod et fructum spinosum habet. The caltrop has the distinctive property that it even has a spiny fruit. There are a few plants called tribulus ‘caltrop’, in both English and Latin.  The one that today has Tribulus as its scientific name, the puncturevine, is probably not the one being referred to, […]
Also tagged 1st century, Pliny, proprietas, translation, tribulus