Taxonomic key of Peperomia in Sikkim Himalaya
1. Plant trailing; leaves abaxially pubescent.................................................................................................................... P. mangalbaria
- Plant erect; leaves abaxially glabrous.................................................................................................................................................2
2. Leaves alternate; cordate at base ....................................................................................................................................... P. pellucida
- Leaves opposite or whorled; base rounded, cuneate or attenuate ......................................................................................................3
3. Spikes finely pubescent; leaves broadly obovate or suborbicular.................................................................................. P. tetraphylla
- Spikes glabrous; leaves narrowly obovate or oblanceolate.............................................................................................. P. heyneana