On the identity of the rubiaceous Timonius quadrasii (Guettardeae: Cinchonoideae): its typification and transfer to Rothmannia (Gardenieae: Ixoroideae)

Abstract

The Philippine endemic Timonius quadrasii Elmer exhibits disparate features against the current delimitation of Timonius, and of the subfamily Cinchonoideae. Morphological examination revealed very short axillary branchlets (brachyblasts) bearing a single leaf creating a 3 : 3 nodal pattern, pseudo-axillary inflorescences and left-contorted corollas, which fits to the delimitation of Rothmannia from the subfamily Ixoroideae. In the present work, T. quadrasii is lectotypfied and the new combination Rothmannia quadrasii (Elmer) J.G. Chavez, Liede & Meve is proposed.

Keywords:

• Rubiaceae
• Timonius
• Rothmannia
• nomenclature
• Philippines
• endemic

Acknowledgements

The authors are indebted to Prof. Dr Charlotte M. Taylor (Missouri Botanical Garden) for the helpful comments and for reviewing an earlier version of the manuscript; Prof. Dr John McNeill (Royal Botanic Garden, Edinburgh) for his aid and advice on the typification; the two anonymous reviewers whose comments improved the manuscript; and to the curators of A, L, P, PNH, US and USTH for loans and/or access to their collections.