Monographs Details: Ravenia ruellioides E. G. H. Oliver
Authority: Maguire, Bassett & Wurdack, John J. 1958. The botany of the Guayana Highland--Part III. Mem. New York Bot. Gard. 10: 1-156.
Description:Distribution and Ecology - VENEZUELA: Bolivar: Cerro Guaiquinima, Eio Paragua, B. Maguire 32941, 32964, 33088, 33089.
R. tatri Gleason, Bull. Torrey Club 58: 376. 1931.
R. ruellioides var. ptariana Steyerin. Fieldiana Bot. 28: 273. 1902.
In addition to these collections, several others have been made in the Gran
Sabana area and five were reported from Cerro Sipapo in Part I of "Botany of
the Guyana Highland.'' At the time of that publication, the species appeared to
be rather uniform, but this large number of subsequent collections has revealed
significant variation in both vegetative and fertile parts. With the large series
of collections now available for study, it is at once obvious that Steyermark's
variety is completely untenable; the characters he uses (op. cit. 273) to separate
the taxa of Guayana from each other are perhaps the most variable ones: the
lengths of the flowering peduncle and of the corollas vary widely and the pubescence
on the lower surfaces of the leaves is just as unreliable for taxonomic
Gleason separated his species (R. tatci) on the relatively broader, shorter
petioled leaves which are more or less obtuse basally, smaller flowers with
glandular sepals, etc. Parts of some of the collections cited above could possibly
be referred to this species but none could be wholly. More detailed studies in
the genus may indicate the desirability of recognizing this group at some level,
but I cannot; it is seemingly only a variant of the variable R. ruellioides.
Distribution:Venezuela South America