Systematics of the Burmannia coelestis complex (Burmanniaceae)

Patterns of morphological variation in the Burmannia coelestis species complex are investigated and three distinct species recognized. Burmannia coelestis sensu stricto (widespread in Asia, extending from eastern Nepal and Assam to New Guinea and northern Australia) possesses outer perianth lobes with conspicuous double margins running the entire lengths of the lobes. The name B. chinensis is revived for specimens from north-eastern India, southern China, northern Indochina and northern Thailand which possess outer perianth lobes with single margins or short double margins. A new species, B. filamentosa, is described from Guangdong province, China; it is distinctive in possessing narrow triangular outer and inner perianth lobes, and stamens with prominent filaments.