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1.
PhytoKeys ; 243: 215-230, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38974889

RESUMO

A new species of Eriotheca (Bombacoideae, Malvaceae) from montane wet forests in the Atlantic Forest of Bahia, northeastern Brazil, is described and illustrated. It is known from only three populations situated between 750 m and 850 m in elevation on mountain summits and categorized as Endangered (EN) based on IUCN criteria. Eriothecapaganuccii is distinct from all congeners by the combination of coriaceous to strongly coriaceous leaves and remarkable few-seeded, globose to subglobose woody capsules that contain scanty kapok and the largest seeds known in the genus to date. The affinities of E.paganuccii to morphologically similar species as well as the importance of obtaining phenologically complete collections are discussed.

2.
PhytoKeys ; 186: 53-72, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34975275

RESUMO

The typification and status of the names of 14 species of Pachira (Malvaceae: Bombacoideae) found in Brazil are discussed, including type material from Brazil, the Guianas, Colombia, Venezuela, and cultivated in Algeria. We designate 11 lectotypes, three neotypes, and four epitypes for these names. Six names are newly considered to be synonyms of the species accepted here. The results support a forthcoming taxonomic treatment of Pachira for the Flora of Brazil.

3.
PhytoKeys ; 167: 31-43, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33304117

RESUMO

A new species of Eriotheca (Malvaceae, Bombacoideae) from coastal areas in the northeastern Brazilian states of Alagoas and Bahia is described and illustrated. Eriotheca alversonii inhabits Atlantic coastal forest and is found principally on sandy soils in restinga vegetation. It is most similar morphologically to E. parvifolia. Both species have 3-foliolate leaves and short petioles on fertile branches, but the new species has smaller flowers, truncate to crenulate calyces, and smaller globose to subglobose capsules. The affinities of E. alversonii to morphologically similar species and its phenology are discussed. A distribution map and preliminary assessment of its conservation status are provided.

4.
Front Plant Sci ; 11: 320, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32318079

RESUMO

Allioideae (e.g., chives, garlics, onions) comprises three mainly temperate tribes: Allieae (800 species from the northern hemisphere), Gilliesieae (80 South American species), and Tulbaghieae (26 Southern African species). We reconstructed the phylogeny of Allioideae (190 species plus 257 species from Agapanthoideae and Amaryllidoideae) based on ITS, matK, ndhF, and rbcL to investigate its historical biogeography and karyotype evolution using newly generated cytomolecular data for Chilean Gilliesieae genera Gethyum, Miersia, Solaria, and Speea. The crown group of Allioideae diversified ∼62 Mya supporting a Gondwanic origin for the subfamily and vicariance as the cause of the intercontinental disjunction of the tribes. Our results support the hypothesis of the Indian tectonic plate carrying Allieae to northern hemisphere ('out-of-India' hypothesis). The colonization of the northern hemisphere (∼30 Mya) is correlated with a higher diversification rate in Allium associated to stable x = 8, increase of polyploidy and the geographic expansion in Europe and North America. Tulbaghieae presented x = 6, but with numerical stability (2n = 12). In contrast, the tribe Gilliesieae (x = 6) varied considerably in genome size (associated with Robertsonian translocations), rDNA sites distribution and chromosome number. Our data indicate that evolutionary history of Allioideae tribes is linked to distinct trends of karyotype evolution.

5.
PhytoKeys ; (85): 27-30, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29033657

RESUMO

Taxonomic notes in the Neotropical genus Pseudobombax (Malvaceae) are presented. One new combination and two new heterotypic synonyms for taxa originally described from Brazil and Ecuador are proposed based on both morphological and previously published molecular evidence. The taxonomic changes will be adopted in a treatment of Pseudobombax for the upcoming Brazilian Flora 2020 and in a forthcoming revision of the genus throughout its range.

6.
Mol Phylogenet Evol ; 101: 56-74, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27154210

RESUMO

Bombacoideae (Malvaceae) is a clade of deciduous trees with a marked dominance in many forests, especially in the Neotropics. The historical lack of a well-resolved phylogenetic framework for Bombacoideae hinders studies in this ecologically important group. We reexamined phylogenetic relationships in this clade based on a matrix of 6465 nuclear (ETS, ITS) and plastid (matK, trnL-trnF, trnS-trnG) DNA characters. We used maximum parsimony, maximum likelihood, and Bayesian inference to infer relationships among 108 species (∼70% of the total number of known species). We analyzed the evolution of selected morphological traits: trunk or branch prickles, calyx shape, endocarp type, seed shape, and seed number per fruit, using ML reconstructions of their ancestral states to identify possible synapomorphies for major clades. Novel phylogenetic relationships emerged from our analyses, including three major lineages marked by fruit or seed traits: the winged-seed clade (Bernoullia, Gyranthera, and Huberodendron), the spongy endocarp clade (Adansonia, Aguiaria, Catostemma, Cavanillesia, and Scleronema), and the Kapok clade (Bombax, Ceiba, Eriotheca, Neobuchia, Pachira, Pseudobombax, Rhodognaphalon, and Spirotheca). The Kapok clade, the most diverse lineage of the subfamily, includes sister relationships (i) between Pseudobombax and "Pochota fendleri" a historically incertae sedis taxon, and (ii) between the Paleotropical genera Bombax and Rhodognaphalon, implying just two bombacoid dispersals to the Old World, the other one involving Adansonia. This new phylogenetic framework offers new insights and a promising avenue for further evolutionary studies. In view of this information, we present a new tribal classification of the subfamily, accompanied by an identification key.


Assuntos
Loci Gênicos , Malvaceae/classificação , Malvaceae/genética , Filogenia , Teorema de Bayes , Bases de Dados Genéticas , Malvaceae/anatomia & histologia , Característica Quantitativa Herdável , Sementes/anatomia & histologia
7.
PhytoKeys ; (21): 53-61, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23794936

RESUMO

In the course of a taxonomic revision of Pseudobombax Dugand, one of us (JGCS) frequently has observed herbarium specimens of Bombacoideae that comprise a mixture of different Angiosperm families. In particular, Pseudobombax heteromorphum (Kuntze) A. Robyns, a frequent name in checklists of the Bolivian flora, is based on type material of Bombax heteromorphum Kuntze that is clearly a mixture of Pseudobombax flowers and Tabebuia Gomes ex DC. (Bignoniaceae) leaves. We herein designate as the lectotype of Bombax heteromorphum the flowers of an herbarium sheet deposited in NY and as epitype a complete specimen (leaves, flowers, and fruit) in HUEFS. We consider Bombax heteromorphum to be a synonym of Pseudobombax longiflorum (Mart.) A. Robyns, a species widespread in Neotropical seasonally dry forest of Bolivia, Brazil, Paraguay, and Peru. Furthermore, we describe a new species, Pseudobombax pulchellum Carv.-Sobr., apparently endemic to seasonally dry tropical forest (SDTF) in Bolivia (Chiquitano dry forest), based on specimens commonly but incorrectly identified as Pseudobombax heteromorphum.We also comment on the morphology, distribution, and conservation status of this new species.


ResumenEn el curso de una revisión taxonómica de Pseudobombax Dugand, uno de nosotros (JGCS) con frecuencia se ha observado especímenes de herbario de Bombacoideae que comprenden una mezcla de diferentes familias de angiospermas. En particular, Pseudobombax heteromorphum (Kuntze) A.Robyns, un nombre frecuente en las listas de la flora boliviana, se basa en el material tipo de Bombax heteromorphum Kuntze que es claramente una mezcla de flores de Pseudobombax y hojas de Tabebuia Gomes ex DC. (Bignoniaceae). Aquí se designa como el lectotipo de Bombax heteromorphum las flores de uno espécimen de el herbario NY y como epitipo uno espécimen completo (hojas, flores y frutos) de el herbario HUEFS. Consideramos Bombax heteromorphum como sinónimo de Pseudobombax longiflorum (Mart.) A.Robyns, una especie ampliamente distribuida en los bosques neotropicales estacionalmente seco de Bolivia, Brasil, Paraguay y Perú. Por otra parte, se describe una especie nueva, Pseudobombax pulchellum Carv.-Sobr., aparentemente endémica de los Bosques secos Chiquitanos en Bolivia, con base en colecciones comúnmente, pero incorrectamente identificado, como Pseudobombax heteromorphum, con comentarios sobre su morfología, distribución y estado de conservación.

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