Clarkella is a monotypic genus of flowering plants in the family Rubiaceae.Hooker, Joseph Dalton. 1880. Flora of British India 3(7): 46. The genus contains only one species, viz. Clarkella nana, which is native to India, China, Uttarakhand, the Western Himalayas, Burma and Thailand.Kew World Checklist of Selected Plant Families, ClarkellaCraib, William Grant. 1931. Bulletin of Miscellaneous Information Kew 1931: 216, Clarkella siamensis from Thailand
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