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1.
PhytoKeys ; 182: 107-112, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34707456

RESUMO

In this study, Indigoferawenholdiae, a new species of Fabaceae from the Agulhas Plain Region of the Western Cape Province, South Africa, is described. A composite photographic plate is included along with a distribution map, description of habitat and ecology and proposed IUCN conservation status. Indigoferawenholdiae is unique in the I.brachystachya group by having digitately compound (vs. pinnately compound) leaves, white and unscented flowers (vs. pink and sweetly scented flowers) and grows on sandstone hillsides (vs. coastal limestone plains and outcrops).

2.
PhytoKeys ; 165: 63-67, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33192146

RESUMO

Two new species from Borneo that have been described in the genus Callerya are shown here to belong in Adinobotrys. The new combinations A. katinganensis and A. sarawakensis have consequently been made, bringing the total number of species in the genus to four. A morphological key and taxonomic conspectus is provided for all species.

3.
PhytoKeys ; 125: 1-112, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31303810

RESUMO

The Tribe Wisterieae (Zhu 1994), founded on the single genus Wisteria, is emended and recircumscribed based on morphology and data from nuclear ITS and ndhJ-trnF, matK and rbcL chloroplast DNA sequences. This newly enlarged tribe comprises 36 species and 9 infraspecific taxa within 13 described genera. Six genera are new, two are reinstated and five were previously placed in Tribe Millettieae. The genus Adinobotrys is also reinstated comprising two species including the new combination A.vastus. Other reinstated genera include Whitfordiodendron, with four species, and Padbruggea, with three species, including the reinstatement of P.filipes and the new combination P.filipesvar.tomentosa. The existing genera Afgekia, Callerya, Endosamara (with the new combination E.racemosavar.pallida), Sarcodum and Wisteria, with the new combinations W.frutescenssubsp.macrostachya are evaluated. The new genera comprise three Australasian species in Austrocallerya: A.australis, A.megasperma and A.pilipes; Wisteriopsis with five species from east Asia has six new combinations: W.japonica, W.kiangsiensis, W.championii, W.eurybotrya, W.reticulata and W.reticulatavar.stenophylla. Two species comprise the new Thai genus Kanburia: K.tenasserimensis and K.chlorantha. Nanhaia comprises the two species: N.fordii and N.speciosa and the monotypic genera Sigmoidala and Serawaia are based respectively on the species S.kityana and S.strobilifera. Lectotypes are designated for the names Adinobotrysfilipes, A.myrianthus, Millettiabonatiana, Millettiabracteosa, Millettiachampionii, Millettiacinerea, Millettiadielsiana, Millettiakityana, M.maingayi, Millettianitida, Millettiaoocarpa, Millettiapurpurea, M.reticulata, M.reticulatavar.stenophylla, Padbruggeadasyphylla, Pterocarpusaustralis, Robiniaracemosa, Whitfordiodendronscandens, W.sumatranum and Wisteriapallida. A neotype is designated for the name Millettialeiogyna.

4.
PhytoKeys ; (48): 29-41, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25941448

RESUMO

Two new species of Indigofera L. (Leguminosae) are described from the Sneeuberg Centre of Floristic Endemism on the southern Great Escarpment, Eastern and Western Cape Provinces, South Africa. Both species are localised high-altitude endemics. Indigoferamagnifica Schrire & V.R. Clark is confined to the summit plateau of the Toorberg-Koudeveldberg-Meelberg west of Graaff-Reinet, and complements other western Sneeuberg endemics such as Ericapasserinoides (Bolus) E.G.H. Oliv. and Faurearecondita Rourke & V.R. Clark. Indigoferaasantasanensis Schrire & V.R. Clark is confined to a small area east of Graaff-Reinet, and complements several other eastern Sneeuberg endemics such as Euryopsexsudans B. Nord & V.R. Clark and Euryopsproteoides B. Nord. & V.R. Clark. Based on morphology, both new species belong to the Cape Clade of Indigofera, supporting a biogeographical link between the Cape Floristic Region and the Sneeuberg, as well as with the rest of the eastern Great Escarpment.

5.
PLoS Biol ; 9(5): e1000620, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21629678

RESUMO

It is widely recognized that we are entering an extinction event on a scale approaching the mass extinctions seen in the fossil record. Present-day rates of extinction are estimated to be several orders of magnitude greater than background rates and are projected to increase further if current trends continue. In vertebrates, species traits, such as body size, fecundity, and geographic range, are important predictors of vulnerability. Although plants are the basis for life on Earth, our knowledge of plant extinctions and vulnerabilities is lagging. Here, we disentangle the underlying drivers of extinction risk in plants, focusing on the Cape of South Africa, a global biodiversity hotspot. By comparing Red List data for the British and South African floras, we demonstrate that the taxonomic distribution of extinction risk differs significantly between regions, inconsistent with a simple, trait-based model of extinction. Using a comprehensive phylogenetic tree for the Cape, we reveal a phylogenetic signal in the distribution of plant extinction risks but show that the most threatened species cluster within short branches at the tips of the phylogeny--opposite to trends in mammals. From analyzing the distribution of threatened species across 11 exemplar clades, we suggest that mode of speciation best explains the unusual phylogenetic structure of extinction risks in plants of the Cape. Our results demonstrate that explanations for elevated extinction risk in plants of the Cape flora differ dramatically from those recognized for vertebrates. In the Cape, extinction risk is higher for young and fast-evolving plant lineages and cannot be explained by correlations with simple biological traits. Critically, we find that the most vulnerable plant species are nonetheless marching towards extinction at a more rapid pace but, surprisingly, independently from anthropogenic effects. Our results have important implications for conservation priorities and cast doubts on the utility of current Red List criteria for plants in regions such as the Cape, where speciation has been rapid, if our aim is to maximize the preservation of the tree-of-life.


Assuntos
Biodiversidade , Extinção Biológica , Especiação Genética , Plantas/genética , Conservação dos Recursos Naturais , Filogenia , Filogeografia , Plantas/classificação , África do Sul
6.
BMC Evol Biol ; 11: 39, 2011 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-21303519

RESUMO

BACKGROUND: The best documented survival responses of organisms to past climate change on short (glacial-interglacial) timescales are distributional shifts. Despite ample evidence on such timescales for local adaptations of populations at specific sites, the long-term impacts of such changes on evolutionary significant units in response to past climatic change have been little documented. Here we use phylogenies to reconstruct changes in distribution and flowering ecology of the Cape flora--South Africa's biodiversity hotspot--through a period of past (Neogene and Quaternary) changes in the seasonality of rainfall over a timescale of several million years. RESULTS: Forty-three distributional and phenological shifts consistent with past climatic change occur across the flora, and a comparable number of clades underwent adaptive changes in their flowering phenology (9 clades; half of the clades investigated) as underwent distributional shifts (12 clades; two thirds of the clades investigated). Of extant Cape angiosperm species, 14-41% have been contributed by lineages that show distributional shifts consistent with past climate change, yet a similar proportion (14-55%) arose from lineages that shifted flowering phenology. CONCLUSIONS: Adaptive changes in ecology at the scale we uncover in the Cape and consistent with past climatic change have not been documented for other floras. Shifts in climate tolerance appear to have been more important in this flora than is currently appreciated, and lineages that underwent such shifts went on to contribute a high proportion of the flora's extant species diversity. That shifts in phenology, on an evolutionary timescale and on such a scale, have not yet been detected for other floras is likely a result of the method used; shifts in flowering phenology cannot be detected in the fossil record.


Assuntos
Biodiversidade , Evolução Biológica , Mudança Climática , Filogenia , Ecologia/métodos , Magnoliopsida/classificação , Magnoliopsida/genética , África do Sul
7.
Am J Bot ; 96(4): 816-52, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21628237

RESUMO

This analysis goes beyond many phylogenies in exploring how phylogenetic structure imposed by morphology, ecology, and geography reveals useful evolutionary data. A comprehensive range of such diversity is evaluated within tribe Indigofereae and outgroups from sister tribes. A combined data set of 321 taxa (over one-third of the tribe) by 80 morphological characters, 833 aligned nuclear ribosomal ITS/5.8S sites, and an indel data set of 33 characters was subjected to parsimony analysis. Notable results include the Madagascan dry forest Disynstemon resolved as sister to tribe Indigofereae, and all species of the large genus Indigofera comprise just four main clades, each diagnosable by morphological synapomorphies and ecological and geographical predilections. These results suggest niche conservation (ecology) and dispersal limitation (geography) are important processes rendering signature shapes to the Indigofereae phylogeny in different biomes. Clades confined to temperate and succulent-rich biomes are more dispersal limited and have more geographical phylogenetic structure than those inhabiting tropical grass-rich vegetation. The African arid corridor, particularly the Namib center of endemism, harbors many of the oldest Indigofera lineages. A rates analysis of nucleotide substitutions confirms that the ages of the oldest crown clades are mostly younger than 16 Ma, implicating dispersal in explaining the worldwide distribution of the tribe.

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