Rhododendron gratum
Billeder af Rhododendron gratum
Beskrivelse
R. rex ssp. gratum (Grandia) (tidligere R. gratum) er beslægtet med R. basilicum. Et kendetegn er at bladstilken er svagt vinget, men noget fladtrykt, medens R. rex er rund. R. basilicum har mere vinget bladstilk.
Hans Eiberg
Flora of China
Leaf blade usually elliptic; abaxial surface indumentum usually discontinuous, transparent or translucent, sometimes quickly lost. Corolla without color flecks. Fl. Apr–May.Rhododendron thickets; ca. 3200 m. W Yunnan.
Field observations at the type locality suggest that subsp. gratum is a form of Rhododendron basilicum with only slightly winged petioles; this fits reasonably well with the distribution of the latter species.
Flora of China
Herbarium; ingen fundet
RBGE Herbarium; R. rex
The taxon was named from the Ziben shan just north of Coajian. David Chamberlain treated it as a synonym of R. basilicum and thinks there is a hybrid swarm at the old tin mine site. Then the Chinese made it a form of rex. More credible, I suspect, is John McQuire’s recent observation on a couple of Alan Clark numbers that it seems closer to R. semnoides. I’ve been to the site twice, in 1993 and 2002, but have killed off my plants. Tom Hudson has it from his first two visits (1993 and a year or two later, he didn’t collect any more in 2002) and I have one of Alan Clark’s numbers, whereas John has two (3009 + 3014).
Looking at the hairs on one of Tom’s plants, they are the open bowl shape for R. basilicum, but strongly fimbriated. Also in the same “pie” are the plants Tom and I collected from Yongdeshan in 2002. Tom flowered one and it had an enormous yellow truss, top quality. Cup shaped hairs, but not R. basilicum nor R. rex in my book.
Keith Rushforth