19 research outputs found
Phylogeny of the carolinense clade of solanum (Solanaceae) inferred from nuclear and plastid DNA sequences
pre-printThe large and economically important genus Solanum contains ca. 1,400 species distributed worldwide. One of the 12-14 major clades identified in the genus is the Leptostemonum clade, or the "spiny solanums." Previous molecular phylogenetic studies have identified 14 major clades in the spiny solanums. Among these is the Carolinense clade, which contains Solanum carolinense, the type species of S. subsect. Lathyrocarpum. However, previous results have suggested that the species composition of the Carolinense clade is only partially congruent with taxonomic circumscriptions of S. subsect. Lathyrocarpum. The main goal of this study was to increase taxon sampling over previous molecular phylogenies in order to better understand the composition of the Carolinense clade. We newly sequenced 31 accessions of 17 taxa putatively belonging to the clade for two nuclear (ITS, waxy) and one plastid gene region (trnT-trnF) and combined these with previously generated molecular data. Phylogenetic analyses of separate and combined DNA matrices were done using maximum parsimony and Bayesian methods. Results from analyses of the combined nuclear and plastid data set showed 10 taxa to be resolved within a wellsupported Carolinense clade. However, three species, Solanum dimidiatum, S. perplexum, and S. hieronymi, showed conflicting placements in phylogenies based on analyses of nuclear vs. plastid data sets, suggesting a history of allopolyploidy or introgression. Within the Carolinense clade, the North and South American species were both recovered as well-supported clades, implying a single dispersal event from South to North America
Les espèces lianescentes de <i>Grewia</i> L. (Malvaceae <i>s.l.</i>, anciennement Tiliaceae) de Madagascar
Trois espèces lianescentes de Grewia L. sont décrites de Madagascar, portant à cinq le nombre de représentants du genre sur l’île caractérisés par ce port. Grewia manomboensis G.E. Schatz, Randrian. & Lowry, sp. nov., G. rabehevitrae Randrian., Lowry & G.E. Schatz, sp. nov. et G. rufostellata Randrian., Lowry & G.E. Schatz, sp. nov., qui croissent toutes les trois dans les forêts orientales de basse à moyenne altitude, peuvent être distinguées les unes des autres par plusieurs caractères, dont des différences foliaires (taille, marge et proéminence de la nervation tertiaire), pédicellaires (longueur, diamètre, densité de trichomes), la taille des sépales, le type et la couleur de l’indument, ainsi que par la forme des pétales. Des illustrations sont fournies pour chacun des nouveaux taxons et des photographies pour deux d’entre eux, ainsi qu’une carte de répartition, une première évaluation du statut de conservation pour chaque espèce et une clé d’identification en anglais et en français.Three liana species of Grewia L. are described from Madagascar, bringing to five the members of the genus on the island to exhibit this habit. Grewia manomboensis G.E. Schatz, Randrian. & Lowry, sp. nov., G. rabehevitrae Randrian., Lowry & G.E. Schatz, sp. nov. and G. rufostellata Randrian., Lowry & G.E. Schatz, sp. nov., all three of which occur in low- to mid-elevation humid eastern forest, can be distinguished from one another by several features, including differences in the leaves (size, margin and prominence of the tertiary venation), pedicels (length, diameter and trichome density), sepal size, indument type and color, and petal shape. Illustrations are provided for each new taxon and photographs for two of them, along with a range map, preliminary assessments of the conservation status of each species, and an identification key in English and French.</p
A New Zygomorphic-Flowered Rinorea (Violaceae) from the Neotropics
Volume: 19Start Page: 416End Page: 42
Phylogeny of the Carolinense Clade of Solanum (Solanaceae) Inferred from Nuclear and Plastid DNA Sequences
The large and economically important genus Solanum contains ca. 1,400 species distributed worldwide. One of the major clades identified in the genus is the Leptostemonum clade, or spiny solanums. Previous molecular phylogenetic studies have identified 14 major clades in the spiny solanums. Among these is the Carolinense clade, which contains Solanum carolinense, the type species of S. subsect. Lathyrocarpum. However, previous results have suggested that the species composition of the Carolinense clade is only partially congruent with taxonomic circumscriptions of S. subsect. Lathyrocarpum. The main goal of this study was to increase taxon sampling over previous molecular phylogenies in order to better understand the composition of the Carolinense clade. We newly sequenced 31 accessions of 17 taxa putatively belonging to the clade for two nuclear (ITS, waxy) and one plastid gene region (trnT-trnF) and combined these with previously generated molecular data. Phylogenetic analyses of separate and combined DNA matrices were done using maximum parsimony and Bayesian methods. Results from analyses of the combined nuclear and plastid data set showed 10 taxa to be resolved within a well-supported Carolinense clade. However, three species, Solanum dimidiatum, S. perplexum, and S. hieronymi, showed conflicting placements in phylogenies based on analyses of nuclear vs. plastid data sets, suggesting a history of allopolyploidy or introgression. Within the Carolinense clade, the North and South American species were both recovered as well-supported clades, implying a single dispersal event from South to North America.Fil: Wahlert, Gregory A.. State University Of Utah; Estados UnidosFil: Chiarini, Franco Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Instituto Multidisciplinario de Biología Vegetal (p); ArgentinaFil: Bohs, Lynn. State University Of Utah; Estados Unido
Phylogeny of the Carolinense Clade of <I>Solanum</I> (Solanaceae) Inferred from Nuclear and Plastid DNA Sequences
A PHYLOGENY OF ARCTOSTAPHYLOS (ERICACEAE) INFERRED FROM NUCLEAR RIBOSOMAL ITS SEQUENCES
Volume: 3Start Page: 673End Page: 68
Phylogeny of the tribes Juanulloeae and Solandreae (Solanaceae)
The tribe Juanulloeae is composed of seven to nine Neotropical genera of lianas and epiphytic or terrestrial shrubs that exhibit a wide variety of floral morphologies and pollination syndromes. Their commonly epiphytic habit in the forest canopy and relatively infrequent flowering has resulted in few and fragmentary specimens and has complicated taxonomic study of the tribe so that many of its genera remain poorly understood. Solandra, currently included in the monotypic tribe Solandreae, is morphologically very similar to the Juanulloeae but its phylogenetic affinities are unclear. In this study, a phylogeny of the Juanulloeae and Solandra was inferred from maximum parsimony and Bayesian analyses of nuclear and plastid DNA sequences (ITS, waxy, trnT-trnF, rps16-trnK). Solandra was strongly supported as sister to the Juanulloeae and the two tribes are combined here under the older name Solandreae. Many genera within the group, notably Juanulloa, Markea, andTrianaea, are not monophyletic as currently circumscribed. We review the morphological characteristics of the genera and clades in light of the phylogenetic evidence presented here and highlight the need to re-evaluate the morphological characters used to delimit genera of the tribe. On the basis of our results, we propose to (1) broaden the circumscription of tribe Solandreae to include tribe Juanulloeae, (2) recognize nine genera in the Solandreae, including the reinstatement of Poortmannia and Hawkesiophyton, and (3) make two new species-level combinations, propose one new species-level synonym, and designatea lectotype for Trianaea neovisae.Fil: Orejuela, Andrés. Universidad Nacional de Colombia; ColombiaFil: Wahlert, Gregory A.. University Of Utah; Estados UnidosFil: Orozco, Clara Inés. Universidad Nacional de Colombia; ColombiaFil: Barboza, Gloria Estela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Bohs, Lynn. University Of Utah; Estados Unido
A Phylogeny of the Violaceae (Malpighiales) Inferred from Plastid DNA Sequences: Implications for Generic Diversity and Intrafamilial Classification
The Violaceae consist of 1,000-1,100 species of herbs, shrubs, lianas, and trees that are placed in 22 recognized genera. In this study we tested the monophyly of genera with a particular focus on the morphologically heterogeneous Rinorea and Hybanthus, the second and third most species-rich genera in the family, respectively. We also investigated intrafamilial relationships in the Violaceae with taxon sampling which included all described genera and several unnamed generic segregates. Phylogenetic inference was based on maximum parsimony, maximum likelihood, and Bayesian analyses of DNA sequences from the trnL/trnL-F and rbcL plastid regions for 102 ingroup accessions. Results from phylogenetic analyses showed Rinorea and Hybanthus to be polyphyletic, with each genus represented by three and nine clades, respectively. Results also showed that most intrafamilial taxa from previous classifications of the Violaceae were not supported. The phylogenetic inferences presented in this study illustrate the need to describe new generic segregates and to reinstate other genera, as well as to revise the traditionally accepted intrafamilial classification, which is artificial and principally based on the continuous and homoplasious character state of floral symmetry