The Wollastonia/Melanthera/Wedelia generic complex (Asteraceae: Ecliptinae), with particular reference to Australia and Malesia
The generic limits of Wedelia Jacq., Melanthera Rohr, and Wollastonia DC. ex Decne., as currently recognised, are re-examined on the basis of comparative morphology, and a new classification recognising the first two genera in a restricted sense is proposed, with other taxa redistributed through nine genera. In this classification, Wedelia (including Aspilia Thouars) with c. 100 species, is restricted to the Americas and Africa. Melanthera is restricted to c. five species of the Caribbean basin and northern Andes. It is proposed that African species formerly in Melanthera be transferred to Lipotriche R.Br. and the following new combinations are made: L. scandens (Schum. & Thonn.) Orchard; L. scandens subsp. subsimplicifolia (Wild) Orchard; L. scandens subsp. dregei (DC.) Orchard; L. triternata (Klatt) Orchard; L. abyssinica (Sch.Bip. ex Rich.) Orchard; L. gambica (Hutch. & Dalziel) Orchard; L. pungens (Oliver & Hiern.) Orchard. The autonym L. scandens subsp. scandens is newly created. Echinocephalum Gardner of South America is resurrected, with a single species (E. latifolium Gardner). It is proposed that Wollastonia be retained as a genus distinct from Wedelia, Melanthera and Lipochaeta DC., with which it has been variously synonymised by recent authors. In Australia two species of Wollastonia are recognised, W. biflora (L.) DC. and W. uniflora (Willd.) Orchard. These species are keyed, described and illustrated. The Hawai‘ian species of Lipochaeta sect. Aphanopappus (Endl.) Benth. & Hook.f. are transferred to Wollastonia, and placement of Wollastonia lifuana (Hochr.) Fosb. of New Caledonia and Vanuatu, and the Asian species Wedelia prostrata Hemsl. in Wollastonia (as Wollastonia dentata) is confirmed. New combinations are made for Wollastonia biflora var. ryukyuensis (H.Koyama) Orchard, W. bryanii (Sherff) Orchard, W. dentata (H.Lév. & Vaniot) Orchard, W. fauriei (H.Lév.) Orchard, W. integrifolia (Nutt.) Orchard, W. kamolensis (O.Deg. & Sherff) Orchard, W. lavarum (Gaudich.) Orchard, W. micrantha (Nutt.) Orchard, W. micrantha subsp. exigua (O.Deg. & Sherff) Orchard, W. perdita (Sherff) Orchard, W. populifolia (Sherff) Orchard, W. remyi (A.Gray) Orchard, W. subcordata (A.Gray) Orchard, W. tenuifolia (A.Gray) Orchard, W. tenuis (O.Deg. & Sherff) Orchard, W. venosa (Sherff) Orchard, W. waimeaensis (H.St.John) Orchard and W. uniflora (Willd.) Orchard. The autonym W. micrantha subsp. micrantha is newly created. Lipochaeta DC. in Hawai‘i is restricted to the species with 4-lobed disc floret corollas, formerly treated as Lipochaeta sect. Lipochaeta. The Australian and New Guinean species formerly placed in Wedelia are transferred to two new genera: Apowollastonia Orchard, with eight species, including four new combinations (A. longipes (Klatt) Orchard, A. spilanthoides (F.Muell.) Orchard, A. stirlingii (Tate) Orchard and A. verbesinoides (Benth.) Orchard) and five new taxa (A. cylindrica Orchard, A. hamersleyensis Orchard, A. hibernica Orchard, A. major Orchard and A. stirlingii subsp. fontaliciana Orchard). The autonym A. stirlingii subsp. stirlingii is newly created, as is the genus Acunniana Orchard, with one species (A. procumbens (DC.) Orchard). In Malesia/Asia, two monotypic new genera are proposed, Indocypraea Orchard (with a single species, I. montana (Blume) Orchard, formerly Wedelia (Wollastonia) montana), and Quadribractea Orchard (with a single species, Q. moluccana (Blume) Orchard, formerly Wedelia moluccana). Five species related to the former Wedelia urticifolia (Blume) DC. are transferred to the new genus Lipoblepharis Orchard (L. urticifolia (Blume) Orchard, with two subspecies L. urticifolia subsp. urticifolia and subsp. hortorum Orchard, L. thailandica (Koyama) Orchard, L. asperrima (Decne.) Orchard, L. stenophylla (Merr.) Orchard and L. floribunda Orchard). Lectotypes are chosen for Verbesina urticifolia Blume, V. moluccana Blume, V. montana Blume, Buphthalmum australe Biehler (≡ Buphthalmum helianthoides sensu Forster), Wedelia spilanthoides F.Muell., Wedelia verbesinoides Benth. and Wedelia stirlingii Tate.