Can campo rupestre vegetation be floristically delimited based on vascular plant genera?

A number of floristic and vegetation studies apply the terms campo rupestre, campo de altitude (or Brazilian páramo), and Tepui to neotropical azonal outcrop and montane vegetation. All of these are known to harbor considerable numbers of endemic plant species and to share several genera. In order to determine whether currently known combinations of vascular plant genera could help circumscribe and distinguish these vegetation types, we selected 25 floras which did not exclude herbs and compiled them into a single database. We then compared the Sørensen similarities of the genus–assemblages using the numbers of native species in the resulting 1945 genera by multivariate analysis. We found that the circumscription of campo rupestre and other Neotropical outcrop vegetation types may not rely exclusively on a combination of genera. [ABSTRACT FROM AUTHOR]