Dimiano (in CC) has identified a potential problem with the species API. see https://github.com/ropensci/rgbif/issues/299 In particular the /species/search route. The gist is that we think there's duplicates returned when paging through that route for a given search. 

This comment https://github.com/ropensci/rgbif/issues/299#issuecomment-378775164  has curl based examples so you can replicate. 

Is it a possible GBIF problem, or are we doing something wrong?

Thanks, Scott