A revision of Orchidaceae from the Kimberley region of Western Australia with new species of tropical Calochilus and Dipodium

Orchidaceae occurring in the Kimberley region of Western Australia are revised. Calochilus barbarossa R.L.Barrett, M.D.Barrett & K.W.Dixon, Calochilus kimberleyensis R.L.Barrett, M.D.Barrett & M.A.Clem., Dipodium ammolithum M.D.Barrett, R.L.Barrett & K.W.Dixon and Dipodium basalticum M.D.Barrett, R.L.Barrett & K.W.Dixon are described and illustrated as new species from the Kimberley, one also occurring in the Northern Territory. The genera Empusa Lindl., Habenaria Willd. s. str., Phoringopsis D.L.Jones & M.A.Clem., Spiranthes Rich. and Zeuxine L. have been added to the Western Australian flora since publication of the Flora of the Kimberley Region. The taxonomic status of a number of tropical Australian Orchidaceae is discussed with recommendations for future research. Descriptions and illustrations are provided for twenty orchid species recorded in the Kimberley Region (one without a verified voucher). Keys are presented to all Kimberley orchid species.