Continuation of this post. I got an answer quite quickly (but after posting the previous post): @larswillighagen @Wikipedia try The Plant List. That's widely accepted: https://t.co/5J0AKPsCzD— R⓪ss Mounce (@rmounce) 20 augustus 2016 The Plant List marks what species are in what genus and family, and groups families in Major Groups, e.g. gymnosperms. It also marks synonyms.