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A new species of Ericaceae from the Gayo Plateau, Aceh Province, Indonesia is described. Rigiolepis gayoensis resembles R. lanceolata but differs by having shorter leaves, non-protruding basal leaf glands, longer flowering pedicels, a glabrous hypanthium, and a dark red or maroon corolla. A detailed morphological description, ecological notes, conservation status, and photographs are presented. The new species represents the third species of Rigiolepis found in the island of Sumatra. A key to the species of Rigiolepis in Sumatra is provided. 

A new micro-endemic species of Rhododendron is described and illustrated from botanical expeditions to the Victoria-Anepahan  Mountain Range on the island of Palawan. It closely resembles Rhododendron wilkiei but differs in having leaves with laminae that are  narrowly elliptic-oblanceolate, have adaxially indistinct venation, and are arranged in 4–8 active and mostly terminal pseudowhorls  along the length of the stem; bracts without scales on the margin; yellow flowers with a red corolla tube interior that is densely hairy  towards the base; and hairy anther filament bases. Morphological and geographical data place the species in Rhododendron sect.  Schistanthe. The new species, together with a first record of Rhododendron vidalii on Palawan as part of this research, represent the  tenth and eleventh members of this genus recorded from the island. A revised key to the Palawan species of Rhododendron is provided. 

Abstract Species radiations, despite immense phenotypic variation, can be difficult to resolve phylogenetically when genetic change poorly matches the rapidity of diversification. Genomic potential furnished by palaeopolyploidy, and relative roles for adaptation, random drift and hybridisation in the apportionment of genetic variation, remain poorly understood factors. Here, we study these aspects in a model radiation,Syzygium, the most species-rich tree genus worldwide. Genomes of 182 distinct species and 58 unidentified taxa are compared against a chromosome-level reference genome of the sea apple,Syzygium grande. We show that whileSyzygiumshares an ancient genome doubling event with other Myrtales, little evidence exists for recent polyploidy events. Phylogenomics confirms thatSyzygiumoriginated in Australia-New Guinea and diversified in multiple migrations, eastward to the Pacific and westward to India and Africa, in bursts of speciation visible as poorly resolved branches on phylogenies. Furthermore, some sublineages demonstrate genomic clines that recapitulate cladogenetic events, suggesting that stepwise geographic speciation, a neutral process, has been important inSyzygiumdiversification.