Paphiopedilum bellatulum (Rchb.f.) Stein is one of five species in the subgenus Brachypetalum (Cribb, 2011).
Photo: PJ Cribb
Of the three subgenera in the genus Paphiopedilum (Paphiopedilum, Parvisepalum and Brachypetalum), Brachypetalum is the smallest and most homogenous group. Restricted in distribution to south-east Asia, all five species are small plants with mottled or tessellated leaves (often densely purple-spotted on the underside), few flowers (< 3) that are whitish to pale yellow with elliptic or circular petals, and a thick-textured lip with an inrolled margin (Cribb, 1998).
All are calcicoles. P. bellatulum, P. concolor and P. niveum are all true lithophytes that grow with their roots attached to limestone rocks, while other species grow in detritus gathered in fissures in eroded limestone or on calcareous soils (Cribb, 1998). For information on cultivation see Karma's blog and photos of this species growing in her Swedish orchidarium: http://www.orchidkarma.com/paphiopedilum-bellatulum/
The classification that we use for emonocot-Cypripedioideae has been imported from the World Checklist (WCSP), which does not provide infra-generic ranks. However we'll be adding these ranks to our site in the next few weeks, using the classification provided by Phil Cribb's monographs. In particular I'm keen to include these ranks in our interactive key to slipper orchid species to guide users to image galleries for these well-defined groups of taxa. An updated version of the key will be available soon.