In preliminary checklists prepared for Sulawesi, as part
of the Tree Flora of Indonesia initiatives, Gardenia was not
listed (Sidiyasa et al. 1989). Subsequently, a revised checklist
was published and enumerated four species of Gardenia
from Sulawesi, i.e. Gardenia affinis Valeton ex Winkl.,
Gardenia forsteniana Miq., Gardenia pelenkahuana Teijs. &
Binn. ex Koord., and an unidentified Gardenia taxon (Kessler
et al. 2002).
In the World Checklist of Rubiaceae database,
only three taxa were listed for Sulawesi, G. forsteniana,
G. mutabilis Reinw. ex Blume, and Gardenia vernicosa Merr. &
L. M. Perry (Govaerts et al. 2012).
A taxonomic review of the species listed as occurring in
Sulawesi revealed that G. affinis was reduced to synonymy
under Porterandia macroptera (Miq.) Tirveng. (Tirvengadum