A reading of what been posted to date got me interested and this is what I found : First as it was pointed out even though the Brazilians reduce Octomeria pinicola to a synonym of warmingii ( example Image 1 "warmingi tesis 1" ), WCPF keeps both as separate and accepted. Second : It Ron also mentioned that a lack of measurements in the descriptions reviewed was problematic , I think I found some descriptions that have measurements (see the images 2 ( tesis 2 ) , 3 ( diagram with scale ) and 4 ("warmingii) . All have measurements or have scales that allow estimations. The sources for 1 to 3 are found in the link that appears after the images submitted " from the thesis of wellington foster" http://www.teses.usp.br/teses/disponiveis/41/41132/tde-28012008-173303/pt-br.php For Image 4 the source is Flora Brasiliensis, enumeratio plantarum in Brasilia hactenus detectarum v.3,pt.4 1893-1896 Page 625 that can be accessed at the Biodiversity library . For Octomeria pinicola I found two links one gives a very old key ( Link one: http://www.biodiversitylibrary.org/pagethumb/137233,500,800 ) and the other a description that has measurements ( Link 2 : http://www.biodiversitylibrary.org/page/137237#page/421/mode/1up ) I hope this can help with the task at had.