Taxonomic revision of the Hoya mindorensis complex (Apocynaceae:-Asclepiadoideae)

Abstract

The Hoya mindorensis complex is revised, types for the names involved are selected, and a new classification of the taxa is proposed. Hoya erythrostemma is separated once again from Hoya mindorensis, Hoya elmeri is identified as an earlier name for Hoya mindorensis subsp. superba, and a further new species, Hoya rintzii, from Peninsular Malaysia, Sumatra and Borneo, is described. A key is provided as an aid to identification.

Keywords:

• Borneo
• Hoya elmeri
• Hoya erythrostemma
• Hoya mindorensis subsp. mendozae
• Hoya mindorensis subsp. superba
• Hoya rintzii
• Indonesia
• Malaysia

Acknowledgements

This study is part of an ongoing research project on the systematics of Marsdenieae. Financial support has been received from the National Parks Board Singapore to Rodda and from Helge Ax:son Johnsons Stiftelse to Simonsson Juhonewe. We would like to thank the curators of the herbaria mentioned in the text for allowing access to the collections and for providing high-quality images of herbarium specimens; David Goyder for providing excellent photographs of R.E. Rintz RER61 (K), an anonymous benefactor for donating a living specimen of H.  mindorensis, Yap Kim Fatt for donating living specimen of H. rintzii, Anthony Lamb for the fruitful discussion on H. rintzii, Linus Gokusing and Surisa Somadee for providing information on the native habitat of H. elmeri, H. erythrostemma and H. mindorensis, and two anonymous reviewers for their valuable comments on the manuscript.