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1.
PhytoKeys ; 119: 53-66, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30936775

RESUMEN

Indigoferamonieriana M.Pignal & L.P.Queiroz, sp. nov. and Indigoferadumbeana M.Pignal & L.P.Queiroz, sp. nov., two new species from New Caledonia, are described and illustrated. Both new species have been collected for a long time, but most herbarium specimens were named as the Australian species Indigoferaaustralis, even though they clearly stand apart from this species and the other New Caledonian species of the genus. Indigoferamonieriana can be diagnosed by the tall virgate shrubby habit, leaves with an articulate rachis and 7-11 widely obovate to orbiculate leaflets with greyish undersurface and almost invisible venation. Indigoferadumbeana can be recognized by the arborescent habit, leaves with 15-19 elliptical leaflets, small, c. 6 mm long flowers, and ellipsoid seeds. Preliminary IUCN assessments are provided for both species. A key is provided for all species of Indigofera recorded from New Caledonia.


RésuméIndigoferamonieriana M.Pignal & L.P.Queiroz, sp. nov. et Indigoferadumbeana M.Pignal & L.P.Queiroz, sp. nov., deux nouvelles espèces de Nouvelle-Calédonie, sont décrites et illustrées. Toutes deux sont récoltées depuis longtemps, mais la plupart des spécimens d'herbier sont rapportés à Indigoferaaustralis, une espèce australienne, même si elles se distinguent clairement de cette espèce et des autres espèces du genre de la Nouvelle-Calédonie. Indigoferamonieriana peut être caractérisée par son port arbustif élevé, ses feuilles avec un rachis articulé et 7­11 folioles largement obovales à orbiculées, une face abaxiale grisâtre et une nervation presque invisible. Indigoferadumbeana se reconnaît à son port arborescent, à ses feuilles avec 15­19 folioles elliptiques, à ses fleurs de petite taille (environ 6 mm de long) et à ses graines ellipsoïdes. Des statuts UICN préliminaires sont proposés. Une clé est fournie pour toutes les espèces d'Indigofera répertoriées en Nouvelle-Calédonie.

2.
Mol Phylogenet Evol ; 122: 46-58, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29371027

RESUMEN

Ficus (Moraceae) is well diversified in the Neotropics with two lineages inhabiting the wet forests of this region. The hemiepiphytes of section Americanae are the most diversified with c. 120 species, whereas section Pharmacosycea includes about 20 species mostly with a terrestrial habit. To reconstruct the biogeographical history and diversification of Ficus in the Americas, we produced a dated Bayesian phylogenetic hypothesis of Neotropical Ficus including two thirds of the species sequenced for five nuclear regions (At103, ETS, G3pdh, ITS/5.8S and Tpi). Ancestral range was estimated using all models available in Biogeobears and Binary State Speciation and Extinction analysis was used to evaluate the role of the initial habit and propagule size in diversification. The phylogenetic analyses resolved both Neotropical sections as monophyletic but the internal relationships between species in section Americanae remain unclear. Ficus started their diversification in the Neotropics between the Oligocene and Miocene. The genus experienced two bursts of diversification: in the middle Miocene and the Pliocene. Colonization events from the Amazon to adjacent areas coincide with the end of the Pebas system (10 Mya) and the connection of landmasses. Divergence of endemic species in the Atlantic forest is inferred to have happened after its isolation and the opening and consolidation of the Cerrado. Our results suggest a complex diversification in the Atlantic forest differing between postulated refuges and more instable areas in the South distribution of the forest. Finally the selection for initial hemiepiphytic habit and small to medium propagule size influenced the diversification and current distribution of the species at Neotropical forests marked by the historical instability and long-distance dispersal.


Asunto(s)
Ficus/clasificación , Américas , Animales , Teorema de Bayes , Biodiversidad , Bosques , Filogenia , Filogeografía
3.
Appl Plant Sci ; 4(1)2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26819856

RESUMEN

PREMISE OF THE STUDY: Senna spectabilis var. excelsa (Fabaceae) is a South and Central American tree of great ecological importance and one of the most common species in several sites of seasonally dry forests. Our goal was to develop microsatellite markers to assess the genetic diversity and structure of this species. METHODS AND RESULTS: We designed and assessed 53 loci obtained from a microsatellite-enriched library and an intersimple sequence repeat library. Fourteen loci were polymorphic, and they presented a total of 39 alleles in a sample of 61 individuals from six populations. The mean values of observed and expected heterozygosities were 0.355 and 0.479, respectively. Polymorphism information content was 0.390 and the Shannon index was 0.778. CONCLUSIONS: Polymorphism information content and Shannon index indicate that at least nine of the 14 microsatellite loci developed are moderate to highly informative, and potentially useful for population genetic studies in this species.

4.
Am J Bot ; 100(2): 403-21, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23378491

RESUMEN

PREMISE OF STUDY: Flowering traits can sometimes be overemphasized in taxonomic classifications. The fused and completely differentiated papilionate floral organs in the neotropical legume trees Vatairea and Vataireopsis were traditionally used in part to ascribe these genera to the tribe Dalbergieae. In contrast, the free and mostly undifferentiated floral parts of Luetzelburgia and Sweetia fit the circumscription of the "primitive" Sophoreae. Such divergent floral morphologies thought to divide deep phylogenetic lineages indeed may be prone to episodic transformation among close papilionoid relatives. METHODS: We sampled 26 of 27 known species of Luetzelburgia, Sweetia, Vatairea, and Vataireopsis in parsimony and Bayesian phylogenetic analyses of nuclear ribosomal ITS/5.8S and six plastid (matK, 3'-trnK, psbA-trnH, trnL intron, rps16 intron, and trnD-T) DNA sequence loci. KEY RESULTS: The analyses of individual and combined data sets strongly resolved the monophyly of each of Luetzelburgia, Sweetia, Vatairea, and Vataireopsis. Vataireopsis was resolved as sister to the rest and the morphologically divergent Luetzelburgia and Vatairea were strongly resolved as sister clades. Floral morphology was generally not a good predictor of phylogenetic relatedness. CONCLUSIONS: Luetzelburgia, Sweetia, Vatairea, and Vataireopsis are unequivocally resolved as the "vataireoid" clade. Fruit and vegetative traits are found to be more phylogenetically conserved than many floral traits. This explains why the identity of the vataireoids has been overlooked or confused. The evolvability of floral traits may also be a general condition among many of the early-branching papilionoid lineages.


Asunto(s)
ADN de Cloroplastos/química , Fabaceae/genética , Flores/anatomía & histología , Filogenia , Evolución Biológica , ADN Intergénico/química , Fabaceae/anatomía & histología , Fabaceae/química
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