This very rare species has a close affinity with Rhododendron facetum
, but differs in the yellowish corolla. The apparent earlier homonym “Rhododendron flaviflorum
Elmer” (Merrill, Enum. Philipp. Fl. Pl. 3: 244. 1923) was cited as a synonym of R
Merrill and was therefore not validly published under Art. 34.1(c) of the Saint Louis Code.