Bine Xue

Further fragmentation of the polyphyletic genus Polyalthia (Annonaceae): molecular phylogenetic support for a broader delimitation of Marsypopetalum

The species-rich genus Polyalthia has previously been shown to be highly polyphyletic, with species represented in at least five different clades. The Polyalthia species that are associated with Marsypopetalum and Trivalvaria (as revealed either by previous phylogenetic studies or inferred on the basis of comparative morphology) were included in a molecular phylogenetic study based on three chloroplast DNA regions (matK, rbcL and trnL-F). Maximum parsimony, maximum likelihood and Bayesian analyses consistently revealed that several Polyalthia species form a well-supported clade with Marsypopetalum pallidum, and that this clade is sister to Trivalvaria. Diagnostic morphological characters for the clades are re-evaluated and shown to be congruent with the molecular phylogeny. Five Polyalthia species (P. crassa, P. littoralis, P. lucida, P. modesta and P. tristis) are accordingly transferred to Marsypopetalum.

Molecular Phylogenetic Support for the Taxonomic Merger of Fitzalania and Meiogyne (Annonaceae): New Nomenclatural Combinations Under the Conserved Name Meiogyne

Abstract Meiogyne (Annonaceae) currently comprises 15 species of trees and shrubs, distributed in India, Southeast Asia, Australasia, Micronesia and Polynesia. Previous molecular phylogenetic studies have shown that the Australian endemic genus Fitzalania (consisting of only two species) is nested within Meiogyne, and preliminary morphological data have indicated that several south Pacific Polyalthia species may be misclassified and also associated with Meiogyne. We use maximum parsimony, maximum likelihood and Bayesian analyses based on seven chloroplast regions (matK, ndhF, ndhF-rpl32, rbcL, rpl32-trnL, trnL-F and ycf1) to reconstruct the most comprehensive phylogeny of Meiogyne available to date, inclusive of 13 Meiogyne species, the two Fitzalania species, as well as four Polyalthia species from Fiji and Tonga. The results show that Fitzalania and the four Polyalthia species are nested within Meiogyne, and that two species, M. cylindrocarpa and M. stenopetala, are not natural as currently defined. Meiogyne cylindrocarpa subsp. trichocarpa and M. stenopetala subsp. insularis are not conspecific with their respective autonymic subspecies and are morphologically distinct. Based on the plastid marker phylogeny, and corroborated by morphological observations, both subspecies are elevated to species rank, and the four Polyalthia species and the two Fitzalania species are transferred to Meiogyne, thereby increasing the number of species in the genus to 24.

Reassessing the taxonomic status of two enigmatic Desmos species (Annonaceae): Morphological and molecular phylogenetic support for a new genus, Wangia

The systematic position of two enigmatic Annonaceae species from China, Desmos saccopetaloides (W. T. Wang) P. T. Li and Desmos yunnanensis (Hu) P. T. Li, has been controversial, with both species having been transferred between several different genera within subfamilies Annonoideae and Malmeoideae. Phylogenetic analyses of eight chloroplast regions (matK, ndhF, ndhF‐rpl32, psbA‐trnH, rbcL, rpl32‐trnL, trnL‐F, and ycf1; ca. 9.2 kb, 66 taxa) unambiguously placed D. saccopetaloides in a subclade of tribe Miliuseae, nested among the genera Monoon, Neo‐uvaria, Phaeanthus, Sageraea, and Stelechocarpus. This relationship was also supported by endosperm rumination patterns in the seed; other morphological characters furthermore indicated that D. saccopetaloides has closer affinities with Monoon, Neo‐uvaria, and Phaeanthus rather than either Sageraea or Stelechocarpus. Desmos saccopetaloides is distinguished from these genera by its leaf‐opposed inflorescences, sepaloid outer petals, saccate inner petals with basal glandular tissue, moniliform monocarps with uniseriate seeds, and rectangular disulculate pollen with two “cryptoapertures.” On the basis of the combined molecular phylogenetic and morphological data, we propose a new genus, Wangia, to accommodate D. saccopetaloides. The molecular phylogenetic analyses furthermore indicated that D. yunnanensis belongs to the genus Dasymaschalon: examination of the type collections revealed that it is conspecific with Dasymaschalon obtusipetalum, although the combination Dasymaschalon yunnanense has nomenclatural priority.

A new species of Goniothalamus (Annonaceae) from Palawan, and a new nomenclatural combination in the genus from Fiji

Abstract A new species, Goniothalamus palawanensis C.C.Tang & R.M.K.Saunders, sp. nov. (Annonaceae), is described from Palawan, Philippines. Goniothalamus palawanensis is most closely related to Goniothalamus amuyon (Blanco) Merr., but differs in its shorter inner petals, hairy ovaries, and funnel-shaped stigmas. A new nomenclatural combination, Goniothalamus angustifolius (A.C.Sm.) B.Xue & R.M.K.Saunders, comb. nov., is furthermore validated to reflect the phylogenetic affinities of a Fijian species previously assigned to Polyalthia.

Alphonsea glandulosa (Annonaceae), a new species from Yunnan, China

Alphonsea glandulosa sp. nov. is described from Yunnan Province in south-west China. It is easily distinguished from all previously described Alphonsea species by the possession of glandular tissue at the base of the adaxial surface of the inner petals. Nectar was observed throughout the flowering period, including the pistillate phase and subsequent staminate phase. Small curculionid beetles were observed as floral visitors and are inferred to be effective pollinators since they carry pollen grains. A phylogenetic analysis was conducted to confirm the placement of this new species within Alphonsea and the evolution of the inner petal glands and specialized pollinator reward tissues throughout the family.

Reassessing morphological homologies in the early-divergent angiosperm Fenerivia (annonaceae) based on floral vascular anatomy: significance for interpreting putative homeotic mutations.

Fenerivia species (Annonaceae) are characterized by a prominent flange immediately below the perianth, which has been interpreted as synapomorphic for the genus. The homology of this flange is controversial: previous studies of Fenerivia heteropetala (an aberrant species, with 12 perianth parts in three whorls) have suggested that the flange may represent a vestigial calyx resulting from a disruption to the homeotic control of organ identity during floral development. Comparative data on floral vasculature in Fenerivia capuronii are presented to elucidate the homology of the flange in other Fenerivia species (which possess nine perianth parts in three whorls, typical of most Annonaceae). The flange in F. capuronii differs from that in F. heteropetala as it is unvascularized. It is nevertheless suggested that the flange is likely to be homologous, and that a homeotic mutation in the F. heteropetala lineage resulted in the formation of a vestigial but vascularized calyx that fused with the otherwise unvascularized flange.

Genus Huberantha (Annonaceae) Revisited: Erection of Polyalthiopsis, a New Genus for H. floribunda, with a New Combination H. luensis

The identity of an enigmatic species Huberantha floribunda (Annonaceae) is reassessed using molecular phylogenetic analyses of up to seven combined plastid markers (matK, ndhF, rbcL, ycf1 exons; trnL intron; trnL-trnF, psbA-trnH intergenic spacers), constituting up to ca. 7 kbp. Huberantha floribunda does not fall into Huberantha clade, but is retrieved as the sister group of Miliusa with no support, necessitating the recognition of a new genus, to accommodate this species. Polyalthiopsis Chaowasku gen. nov. along with Huberantha and Miliusa form an unsupported to weakly supported clade within the tribe Miliuseae. Morphology of Polyalthiopsis is somewhat intermediate between morphologies of Huberantha and Miliusa. It primarily differs from Huberantha by often possessing unequal petal whorls and a seed raphe that is broadly grooved and partially slightly raised in the middle. Polyalthiopsis differs from Miliusa mainly by having a dilated truncate connective apex of the stamens and outer petals that are much larger than the sepals. In addition, Huberantha luensis (Pierre) Chaowasku, a new combination for Polyalthia luensis is made based on an integrative approach of morphological examination coupled with molecular phylogenetic inferences.