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1.
Am J Bot ; 111(1): e16259, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38031479

RESUMO

PREMISE: The rise of angiosperm-dominated tropical rainforests has been proposed to have occurred shortly after the Cretaceous-Paleogene transition. Paleocene fossil wood assemblages are rare yet provide important data for understanding these forests and whether their wood anatomical features can be used to document the changes that occurred during this transition. METHODS: We used standard techniques to section 11 fossil wood specimens of Paleocene-age, described the anatomy using standard terminology, and investigated their affinities to present-day taxa. RESULTS: We report here the first middle Paleocene fossil wood specimens from Myanmar, which at the time was near the equator and anchored to India. Some fossils share affinities with Arecaceae, Sapindales (Anacardiaceae, Meliaceae) and Moraceae and possibly Fabaceae or Lauraceae. One specimen is described as a new species and genus: Compitoxylon paleocenicum gen. et sp. nov. CONCLUSIONS: This assemblage reveals the long-lasting presence of these aforementioned groups in South Asia and suggests the early presence of multiple taxa of Laurasian affinity in Myanmar and India. The wood anatomical features of the dicotyledonous specimens reveal that both "modern" and "primitive" features (in a Baileyan scheme) are present with proportions similar to features in specimens from Paleocene Indian localities. Their anatomical diversity corroborates that tropical flora display "modern" features early in the history of angiosperms and that their high diversity remained steady afterward.


Assuntos
Fósseis , Magnoliopsida , Madeira , Mianmar , Índia
2.
Plants (Basel) ; 11(3)2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-35161233

RESUMO

Fruits historically have been the key character for delimitation of tribes in the Burseraceae. However, fruit structure is incompletely known within the family, thus the importance of this character is unclear. This study of fruit anatomy in the traditional tribe Canarieae examines the distribution of the tissues that correspond to the exo-, meso-, and endocarp. The detailed arrangement and measurement of the tissues are reported here for the first time in all eight genera in the tribe. The evidence suggests that in all cases except Pseudodacryodes, the endocarp has at least one layer of parenchyma cells within which a sclereid layer is evident and, in some cases, an inner epidermis. All Canarieae fruits exhibit secretory canals, and some taxa have epidermal glands with resin-like contents. Evidence of carpellar sutures was found for all Canarieae, and in Dacryodes, Haplolobus, Rosselia, and Santiria, an articulated plate is present that corresponds to an abortive locule. The anatomical and morphological characters presented here are useful in delimiting genera within Canarieae.

3.
J Bioinform Comput Biol ; 19(6): 2140008, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34806950

RESUMO

Using RACCROCHE, a method for reconstructing gene content and order of ancestral chromosomes from a phylogeny of extant genomes represented by the gene orders on their chromosomes, we study the evolution of three orders of woody plants. The method retrieves the monoploid complement of each Ancestor in a phylogeny, consisting a complete set of distinct chromosomes, despite some of the extant genomes being recently or historically polyploidized. The three orders are the Sapindales, the Fagales and the Malvales. All of these are independently estimated to have ancestral monoploid number [Formula: see text].


Assuntos
Evolução Molecular , Genoma , Cromossomos , Filogenia
4.
J Agric Food Chem ; 69(31): 8838-8849, 2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34339210

RESUMO

Xyloglucans are the dominant hemicelluloses in the primary cell wall of dicotyledonous plants, fulfilling numerous functions. However, routine methods of cell wall analytical chemistry such as methylation analysis are time-consuming and often not adequate to capture the structural diversity of xyloglucans. Here, a xyloglucan profiling method based on the enzymatic release of xyloglucan oligosaccharides by a xyloglucan-specific endo-ß-(1→4)-glucanase and subsequent analysis of these oligosaccharides by high-performance anion-exchange chromatography (HPAEC) with parallel pulsed amperometric and mass spectrometric detection was developed. For this purpose, a set of 23 authentic xyloglucan oligosaccharides was generated, structurally characterized by mass spectrometry and NMR spectroscopy, and established as analytical standard compounds. Coupling of HPAEC with parallel electrochemical and MS detection was demonstrated to be an excellent tool to analyze xyloglucan-derived oligosaccharides. The applicability of the method was demonstrated by characterizing the xyloglucan architecture from a set of nine economically relevant food plants from the botanical orders Caryophyllales (rhubarb, buckwheat, amaranth, and quinoa), Cucurbitales (Hokkaido squash), Laurales (avocado), Myrtales (pomegranate), and Sapindales (mango and orange) for the first time. In future studies, this method can ideally be used to monitor structural alterations of xyloglucans as a result of genetic engineering, plant/tissue maturation, and processing of plant material.


Assuntos
Plantas Comestíveis , Xilanos , Ânions , Cromatografia , Glucanos , Espectrometria de Massas , Oligossacarídeos , Polissacarídeos
5.
Am J Bot ; 108(7): 1234-1251, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34219219

RESUMO

PREMISE: The economically important, cosmopolitan soapberry family (Sapindaceae) comprises ca. 1900 species in 144 genera. Since the seminal work of Radlkofer, several authors have attempted to overcome challenges presented by the family's complex infra-familial classification. With the advent of molecular systematics, revisions of the various proposed groupings have provided significant momentum, but we still lack a formal classification system rooted in an evolutionary framework. METHODS: Nuclear DNA sequence data were generated for 123 genera (86%) of Sapindaceae using target sequence capture with the Angiosperms353 universal probe set. HybPiper was used to produce aligned DNA matrices. Phylogenetic inferences were obtained using coalescence-based and concatenated methods. The clades recovered are discussed in light of both benchmark studies to identify synapomorphies and distributional evidence to underpin an updated infra-familial classification. KEY RESULTS: Coalescence-based and concatenated phylogenetic trees had identical topologies and node support, except for the placement of Melicoccus bijugatus Jacq. Twenty-one clades were recovered, which serve as the basis for a revised infra-familial classification. CONCLUSIONS: Twenty tribes are recognized in four subfamilies: two tribes in Hippocastanoideae, two in Dodonaeoideae, and 16 in Sapindoideae (no tribes are recognized in the monotypic subfamily Xanthoceratoideae). Within Sapindoideae, six new tribes are described: Blomieae Buerki & Callm.; Guindilieae Buerki, Callm. & Acev.-Rodr.; Haplocoeleae Buerki & Callm.; Stadmanieae Buerki & Callm.; Tristiropsideae Buerki & Callm.; and Ungnadieae Buerki & Callm. This updated classification provides a backbone for further research and conservation efforts on this family.


Assuntos
Sapindaceae , Evolução Biológica , Filogenia , Sapindaceae/genética
6.
Phytochemistry ; 185: 112668, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33743499

RESUMO

We review glucosinolate (GSL) diversity and analyze phylogeny in the crucifer tribe Cardamineae as well as selected species from Brassicaceae (tribe Brassiceae) and Resedaceae. Some GSLs occur widely, while there is a scattered distribution of many less common GSLs, tentatively sorted into three classes: ancient, intermediate and more recently evolved. The number of conclusively identified GSLs in the tribe (53 GSLs) constitute 60% of all GSLs known with certainty from any plant (89 GSLs) and apparently unique GSLs in the tribe constitute 10 of those GSLs conclusively identified (19%). Intraspecific, qualitative GSL polymorphism is known from at least four species in the tribe. The most ancient GSL biosynthesis in Brassicales probably involved biosynthesis from Phe, Val, Leu, Ile and possibly Trp, and hydroxylation at the ß-position. From a broad comparison of families in Brassicales and tribes in Brassicaceae, we estimate that a common ancestor of the tribe Cardamineae and the family Brassicaceae exhibited GSL biosynthesis from Phe, Val, Ile, Leu, possibly Tyr, Trp and homoPhe (ancient GSLs), as well as homologs of Met and possibly homoIle (intermediate age GSLs). From the comparison of phylogeny and GSL diversity, we also suggest that hydroxylation and subsequent methylation of indole GSLs and usual modifications of Met-derived GSLs (formation of sulfinyls, sulfonyls and alkenyls) occur due to conserved biochemical mechanisms and was present in a common ancestor of the family. Apparent loss of homologs of Met as biosynthetic precursors was deduced in the entire genus Barbarea and was frequent in Cardamine (e.g. C. pratensis, C. diphylla, C. concatenata, possibly C. amara). The loss was often associated with appearance of significant levels of unique or rare GSLs as well as recapitulation of ancient types of GSLs. Biosynthetic traits interpreted as de novo evolution included hydroxylation at rare positions, acylation at the thioglucose and use of dihomoIle and possibly homoIle as biosynthetic precursors. Biochemical aspects of the deduced evolution are discussed and testable hypotheses proposed. Biosyntheses from Val, Leu, Ile, Phe, Trp, homoPhe and homologs of Met are increasingly well understood, while GSL biosynthesis from mono- and dihomoIle is poorly understood. Overall, interpretation of known diversity suggests that evolution of GSL biosynthesis often seems to recapitulate ancient biosynthesis. In contrast, unprecedented GSL biosynthetic innovation seems to be rare.


Assuntos
Barbarea , Brassicaceae , Acilação , Brassicaceae/genética , Glucosinolatos , Filogenia
7.
Mol Phylogenet Evol ; 154: 106971, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33035682

RESUMO

Subtribe Galipeinae (tribe Galipeeae) is the most diverse group of Rutaceae (the orange family) in the Neotropics, with 27 genera and ca. 130 species. The largest genus in the subtribe is Conchocarpus, with ca. 50 species, distributed from Central America to southern Brazil, and is particularly diverse in the Brazilian Atlantic Forest. The circumscription of the genus was recently changed to accommodate the species of Almeidea. However, even with this inclusion, Conchocarpus did not appear as monophyletic because the position of C. concinnus, which appeared in a clade with the other genera of Galipeinae rather than in the clade with the other species of Conchocarpus. The objective of the present study is to investigate the phylogenetic position of four other species of Conchocarpus (hereafter called "C. gauchaudianus group") that share morphological traits and geographical distribution with C. concinnus suggesting a close phylogenetic affinity. Phylogenetic analyses were based on morphological and molecular data from nuclear regions ITS-1 and ITS-2 as well as plastid regions trnL-trnF and rps-16, and were conducted with parsimony and Bayesian inference as optimization criteria. Results showed Conchocarpus as polyphyletic with its species divided in two clades, one, herein called "the Conchocarpus sensu stricto group," includes the type species C. macrophyllus, and the other "the Conchocarpus gaudichaudianus group" includes C. concinnus. The latter group is here recognized as a new genus, Dryades, the name given by Carl Friederich von Martius (1794-1868) to the Domain of the Atlantic Forest in Brazil, inspired by the tree nymphs in Greek mythology. Floral structure and leaf morphology provided further support to the findings of phylogenetic analysis. A description of the new genus, new combinations, a key to the species of the new genus, discussions of the affinities of the species are also provided, as well as data on the conservation status of the species of Dryades. Additionally, new data on floral structure of C. heterophyllus, C. macrophyllus and C. minutiflorus (all from the Conchocarpus sensu stricto group) are provided.


Assuntos
Segregação de Cromossomos , Florestas , Rutaceae/classificação , Clima Tropical , Teorema de Bayes , Brasil , América Central , Flores/anatomia & histologia , Fenótipo , Filogenia , Folhas de Planta/anatomia & histologia , Rutaceae/embriologia , Especificidade da Espécie
8.
PhytoKeys ; 165: 115-126, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33192150

RESUMO

Thinouia is a Neotropical genus of lianas with approximately 12 species and is the only genus in tribe Paullinieae with actinomorphic flowers. During a taxonomic revision of the genus and fieldwork in south-western Amazonia, we found a new species that appears similar to Thinouia trifoliata (ex Allosanthus) because of its racemiform inflorescence. However, before describing the new species, we had to confirm that Allosanthus was congeneric with Thinouia so we could place the new species in the correct genus. The results of the phylogenetic analysis, based on molecular data (trnL intron and ITS sequences), show that Allosanthus should be included in Thinouia. Thus, the new taxon is described here as Thinouia cazumbensis sp. nov. The new species is described, illustrated and phylogenetic trees showing relationships within supertribe Paulliniodae and Thinouia and the congeneric Allosanthus are given.

9.
PeerJ ; 8: e9315, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32587799

RESUMO

Plastid genomes (plastomes) represent rich sources of information for phylogenomics, from higher-level studies to below the species level. The genus Rhus (sumac) has received a significant amount of study from phylogenetic and biogeographic perspectives, but genomic studies in this genus are lacking. Rhus integrifolia and R. ovata are two shrubby species of high ecological importance in the southwestern USA and Mexico, where they occupy coastal scrub and chaparral habitats. They hybridize frequently, representing a fascinating system in which to investigate the opposing effects of hybridization and divergent selection, yet are poorly characterized from a genomic perspective. In this study, complete plastid genomes were sequenced for one accession of R. integrifolia and one each of R. ovata from California and Arizona. Sequence variation among these three accessions was characterized, and PCR primers potentially useful in phylogeographic studies were designed. Phylogenomic analyses were conducted based on a robustly supported phylogenetic framework based on 52 complete plastomes across the order Sapindales. Repeat content, rather than the size of the inverted repeat, had a stronger relative association with total plastome length across Sapindales when analyzed with phylogenetic least squares regression. Variation at the inverted repeat boundary within Rhus was striking, resulting in major shifts and independent gene losses. Specifically, rps19 was lost independently in the R. integrifolia-ovata complex and in R. chinensis, with a further loss of rps22 and a major contraction of the inverted repeat in two accessions of the latter. Rhus represents a promising novel system to study plastome structural variation of photosynthetic angiosperms at and below the species level.

10.
Plants (Basel) ; 9(2)2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-32098193

RESUMO

Picramniaceae is the only member of Picramniales which is sister to the clade (Sapindales (Huerteales (Malvales, Brassicales))) in the rosidsmalvids. Not much is known about most aspects of their ecology, geography, and morphology. The family is restricted to American tropics. Picramniaceae representatives are rich in secondary metabolites; some species are known to be important for pharmaceutical purposes. Traditionally, Picramniaceae was classified as a subfamily of Simaroubaceae, but from 1995 on, it has been segregated containing two genera, Picramnia and Alvaradoa, with the recent addition of a third genus, Nothotalisia, described in 2011. Only a few species of the family have been the subject of DNA-related research, and fewer than half of the species have been included in morphological phylogenetic analyses. It is clear that Picramniaceae remains a largely under-researched plant group. Here we present the first molecular phylogenetic tree of the group, based on both chloroplast and nuclear markers, widely adopted in the plant DNA barcoding. The main findings are: The family and its genera are monophyletic and Picramnia is sister to two other genera; some clades corroborate previous assumptions of relationships made on a morphological or geographical basis, while most parts of the molecular topology suggest high levels of homoplasy in the morphological evolution of Picramnia.

11.
Am J Bot ; 107(1): 139-147, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31903551

RESUMO

PREMISE: The mahogany family (Meliaceae) is an angiosperm lineage comprising many species that are important elements in tropical ecosystems, and is often used as a study system to understand the evolution of tropical rainforests. While divergence time studies have estimated a Cretaceous origin for the family, no unequivocal fossils of that age have been described. Here, the first Cretaceous evidence for Meliaceae is reported, based on an exceptionally well-preserved fruit from the Upper Cretaceous (79-72 Ma, Campanian) of North America. METHODS: The fossil fruit was prepared using traditional paleobotanical techniques. Bayesian phylogenetic analyses using morphological and molecular data were conducted to assess the phylogenetic position of the Cretaceous fruit in Meliaceae and to assess the effect of morphology for inferring the overall pattern of phylogeny for the family. RESULTS: The fruit consists of a fleshy mesocarp and a woody endocarp with a hollow center, nine locules, loculicidal sutures, and one subapically attached seed per locule that has an enlarged sarcotesta near the hilum. The combination of characters in this fruit is strikingly similar to the genus Melia L. Phylogenetic analyses recover the Cretaceous fruit as being closely related to Melia and highlights the effect of fruit morphological data for inferring the overall pattern of phylogeny in Meliaceae. There are a few structural differences between the fossil fruit of this study and Melia; thus, the newly characterized Cretaceous taxon is named Manchestercarpa vancouverensis gen. et sp. nov. DISCUSSION: These results clearly confirm a Cretaceous origin for Meliaceae and that important tropical families were present prior to the development of modern tropical ecosystems in the Cenozoic.


Assuntos
Fósseis , Meliaceae , Teorema de Bayes , Ecossistema , América do Norte , Filogenia
12.
Mol Phylogenet Evol ; 133: 302-351, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30326286

RESUMO

Schinus, best known by its few cultivated and invasive species, is the largest genus of Anacardiaceae in southern South America. It is remarkably diverse compared to closely related genera, with approximately 42 species, most of which occur in several arid vegetation types and extend into Andean and Atlantic moist forests. The most comprehensive taxonomic revision of the genus dates to 1957, recognizing S. subg. Schinus and S. subg. Duvaua, the latter of which were further divided into two sections. Subsequent studies have highlighted morphological inconsistencies in this infrageneric classification, and species delimitation remains a challenge. Schinus has been poorly sampled in previous phylogenetic studies of Anacardiaceae, and thus any assumptions about its monophyly and relationships remain untested. We investigated the phylogenetic relationships of 44 Schinus taxa and sampled 122 specimens, including the outgroup, using nine nuclear and two plastid DNA sequence regions, most of them developed recently for Commiphora (Burseraceae, sister to Anacardiaceae). We used maximum parsimony, maximum likelihood, and Bayesian inference to infer relationships among species. We also constructed a morphological dataset, including vegetative anatomical features, and compared these characters to hypotheses based on molecular evidence in order to achieve a better understanding of the relationships among the species of Schinus and to related genera, aiming also to identify morphological characters and putative synapomorphies for major clades, and to discuss hypotheses regarding the evolution of structural traits in the genus. Our analyses strongly support the monophyly of Schinus, but also indicate that S. subg. Schinus and the sections of S. subg. Duvaua are polyphyletic. The phylogenetic relationships that emerged from our analyses include eight relatively well-supported lineages, but relationships among closely related species remain unclear in some clades. Ancestral state reconstructions demonstrate that several morphological and leaf-anatomical characters are valuable in characterizing some lineages. By contrast, most of the traits that have traditionally been used to circumscribe groups in Schinus show high levels of homoplasy. In light of these results, we present a novel sectional classification of Schinus based on a combination of character states associated with geographic distribution, corresponding to lineages that are mostly allopatric or at least ecologically distinct.


Assuntos
Anacardiaceae/anatomia & histologia , Anacardiaceae/classificação , Evolução Biológica , Flores/anatomia & histologia , Filogenia , Característica Quantitativa Herdável , Sequência de Bases , Teorema de Bayes , DNA de Plantas/genética , Plastídeos/genética
13.
Appl Plant Sci ; 6(4): e1040, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30131882

RESUMO

PREMISE OF THE STUDY: Toona (Meliaceae, Sapindales) is a small genus of five species of trees native from southern and eastern Asia to New Guinea and Australia. Complete plastomes were sequenced for three Toona species to provide a basis for future plastome genetic studies in threatened species of Toona. In addition, plastome structural evolution and phylogenetic relationships across Sapindales were explored with a larger data set of 29 Sapindales plastomes (including members of six out of nine families). METHODS: The plastomes were determined using the Illumina sequencing platform; the phylogenetic analyses were conducted using maximum likelihood by RAxML. RESULTS: The lengths of three Toona plastomes range from 159,185 to 158,196 bp. A total of 113 unique genes were found in each plastome. Across Sapindales, plastome gene structure and content were largely conserved, with the exception of the contraction of the inverted repeat region to exclude ycf1 in some species of Rutaceae and Sapindaceae, and the movement of trnI-GAU and trnA-UGC to a position outside the inverted repeat region in some Rutaceae species. DISCUSSION: The three Toona plastomes possess the typical structure of angiosperm plastomes. Phylogenomic analysis of Sapindales recovered a mostly strongly supported phylogeny of Sapindales, including most of the backbone relationships, with some improvements compared to previous targeted-gene analyses.

14.
Int J Mol Sci ; 19(4)2018 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-29561773

RESUMO

Ailanthus altissima (Mill.) Swingle (Simaroubaceae) is a deciduous tree widely distributed throughout temperate regions in China, hence suitable for genetic diversity and evolutionary studies. Previous studies in A. altissima have mainly focused on its biological activities, genetic diversity and genetic structure. However, until now there is no published report regarding genome of this plant species or Simaroubaceae family. Therefore, in this paper, we first characterized A. altissima complete chloroplast genome sequence. The tree of heaven chloroplast genome was found to be a circular molecule 160,815 base pairs (bp) in size and possess a quadripartite structure. The A. altissima chloroplast genome contains 113 unique genes of which 79 and 30 are protein coding and transfer RNA (tRNA) genes respectively and also 4 ribosomal RNA genes (rRNA) with overall GC content of 37.6%. Microsatellite marker detection identified A/T mononucleotides as majority SSRs in all the seven analyzed genomes. Repeat analyses of seven Sapindales revealed a total of 49 repeats in A. altissima, Rhus chinensis, Dodonaea viscosa, Leitneria floridana, while Azadirachta indica, Boswellia sacra, and Citrus aurantiifolia had a total of 48 repeats. The phylogenetic analysis using protein coding genes revealed that A. altissima is a sister to Leitneria floridana and also suggested that Simaroubaceae is a sister to Rutaceae family. The genome information reported here could be further applied for evolution and invasion, population genetics, and molecular studies in this plant species and family.


Assuntos
Ailanthus/genética , Genoma de Cloroplastos , Clima Tropical , Aminoácidos/genética , Sequência de Bases , Mapeamento Cromossômico , Códon/genética , Rearranjo Gênico/genética , Genes de Plantas , Repetições de Microssatélites , Filogenia , Edição de RNA/genética
15.
PhytoKeys ; (114): 95-113, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30627043

RESUMO

Six new species are described in the large Neotropical genus Paullinia (Sapindaceae), P.cidii, P.decorticans, P.fruticosa, P.hondurensis; P.martinellii and P.wurdackii. In addition, they are illustrated and contrasted to the morphologically most similar species currently known. The new species were discovered while working on a forthcoming revision of the genus.


ResumoAo trabalhar na revisão do grande gênero neotropical Paullinia, descobrimos várias espécies novas para a ciência, dentre estas, seis são descritas P.cidii, P.decorticans, P.fruticosa, P.hondurensis, P.martinellii e P.wurdackii. Além disso, estas são ilustradas e contrastadas com outras espécies conhecidas atualmente mais morfologicamente semelhantes.

16.
Mitochondrial DNA B Resour ; 3(2): 730-731, 2018 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-33474301

RESUMO

Atalantia kwangtungensis (Rutaceae) is a small shrub (1-2 m tall) distributed in moist and shady places throughout evergreen broad-leaved forests having altitudes that range from 100 to 400 m in West Guangdong, Southeast Guangxi, Hainan province of China. It has been ranked as a near threatened (NT) species in China. Here, we report and characterize the complete plastid genome sequence of A. kwangtungensis in an effort to provide genomic resources useful for its conservation. The complete plastome is 160,248 bp in length and contains the typical structure and gene content of angiosperm plastomes, including two inverted repeat (IR) regions of 27,151 bp, a large single-copy (LSC) region of 87,483 bp and a small single-copy (SSC) region of 18,463 bp. The plastome contains 110 genes, consisting of 77 unique protein-coding genes (ycf1 is a pseudogene), 29 unique tRNA genes, and 4 unique rRNA genes. The overall A/T content in the plastome of A. kwangtungensis is 61.6%. Phylogenetic analyses were performed using the entire plastome, including spacers, introns, etc., and we determined that A. kwangtungensis and Merrillia caloxylon were closely related. The complete plastome sequence of A. kwangtungensis will provide a useful resource for the conservation genetics of this species as well as for the phylogenetic studies in Sapindales.

17.
Mol Phylogenet Evol ; 120: 63-82, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29222065

RESUMO

Generic circumscriptions in the mostly pantropical family Simaroubaceae are somewhat controversial. Simaba is the largest genus, currently defined as exclusively neotropical, with around 25 species of trees and shrubs, but both its limits and infrageneric classification have been a matter of discussion and divergence. Traditionally, species of the genus have been treated in three sections: Simaba sect. Tenuiflorae, S. sect. Floribundae and S. sect. Grandiflorae, but a phylogenetic analysis suggested that the latter two may not be monophyletic. To test the monophyly of Simaba and its infrageneric classification, we used a molecular approach based on DNA sequence data from two nuclear ribosomal spacer regions (ITS and ETS) and three plastid regions (rps16 intron, and intergenic spacers psbA-trnH and trnL-trnF), including a comprehensive sampling of species from Simaba and closely related genera. We also performed ancestral character reconstructions to identify morphological characters that could serve as synapomorphies for major clades and to explore patterns of homoplasy in the morphological dataset. Our results show Simaba as traditionally circumscribed is not monophyletic, with taxa segregated into two strongly supported but distinct clades, one of which is more closely related to Simarouba. The three main clades that emerged in the phylogeny include a mostly Amazonian Simaba clade (which includes the type species of Simaba and the remaining species of S. sect. Tenuiflorae, here proposed to be recognized as Simaba sensu stricto), a mostly extra-Amazonian Simaba clade (a distinct lineage that will be recognized as Homalolepis, a genus currently treated in synonymy and equivalent to Simaba sections Grandiflorae and Floribundae), and the Simarouba clade (including all of its current species). These three clades are characterized by a combination of morphological characters, described in detail herein, some of which are novel features for Simaba not previously reported in the literature. Mapping character-states on the phylogenetic tree provides tests for evolutionary hypotheses. For example, our reconstruction of habit and geographic distribution suggests that the diversification of several shrubby species within the extra-Amazonian lineage in the South American cerrados probably occurred from ancestors inhabiting tropical forests, involving transitions in morphological and ecological traits.


Assuntos
Filogenia , Simaroubaceae/classificação , Simaroubaceae/genética , Sequência de Bases , Teorema de Bayes , Núcleo Celular/genética , Sequência Consenso , DNA de Plantas/genética , Geografia , Íntrons/genética , Análise de Sequência de DNA , Simaroubaceae/anatomia & histologia , Simaroubaceae/ultraestrutura , Especificidade da Espécie
18.
PhytoKeys ; (76): 89-113, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28228688

RESUMO

Two new species of Protium (Burseraceae) are described and illustrated: Protium aguilariisp. nov., from the Pacific slope of the Osa Peninsula, Puntarenas Province, Costa Rica; and Protium hammeliisp. nov., from wet forests on the Caribbean slopes of Nicaragua and Costa Rica. In addition, Protium brenesiicomb. nov., is proposed as a new combination based on Trichilia brenesii, a name that was based on a specimen collected with flowers in the mountains near San Ramón, Alajuela Province, Costa Rica. It is compared with Protium costaricense, a similar species with which it has been confused for more than 90 years. Finally, illustrations and specimen citations are provided for all the aforementioned taxa, and some others with which they have been confused.


ResumenSe describen e ilustran dos nuevas especies de Protium (Burseraceae): Protium aguilariisp. nov., de la vertiente del Pacífico en la Península de Osa, provincia de Puntarenas, Costa Rica; y Protium hammeliisp. nov., de los bosques húmedos de la vertiente del Caribe en Nicaragua y Costa Rica. Además, se propone la combinación Protium brenesiicomb. nov., basada en Trichilia brenesii, un nombre que fue descrito en base en un ejemplar con flores recolectado en las montañas de San Ramón, provincia de Alajuela, Costa Rica. Se compara con Protium costaricense, especie similar, con la cual se confundió por más de 90 años. Finalmente, se proveen ilustraciones y listas de los ejemplares examinados para todos los taxones antes mencionados, y además algunos otros similares.

19.
Mycologia ; 106(5): 989-1003, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24891410

RESUMO

Four new resinicolous species of Chaenothecopsis are described from China: Chaenothecopsis perforata from exudate of Rhus chinensis (Anacardiaceae), C. pallida from exudate of Ailanthus altissima (Simaroubaceae), C. resinophila from exudate of Kalopanax septemlobus (Araliaceae) and C. hunanensis from resin of Pinus massoniana (Pinaceae). All the new species are compared with previously described resinicolous mycocalicioid taxa, and several new features in these species are presented. The newly described species cannot always be distinguished by any single character, but they all possess unique combinations of morphological, chemical and ecological features. Several aspects in the ecology and evolution of boreal and tropical resinicolous species are briefly discussed.


Assuntos
Ascomicetos/classificação , Magnoliopsida/microbiologia , Traqueófitas/microbiologia , Ascomicetos/citologia , Ascomicetos/genética , Ascomicetos/isolamento & purificação , Sequência de Bases , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Carpóforos , Magnoliopsida/química , Dados de Sequência Molecular , Filogenia , Exsudatos de Plantas , Resinas Vegetais , Análise de Sequência de DNA , Esporos Fúngicos , Traqueófitas/química
20.
Mol Phylogenet Evol ; 73: 65-76, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24495856

RESUMO

Similar to other species-rich taxa in the Indo-Australian Archipelago, taxonomy of the genus Aglaia (mahogany family, Meliaceae) remains problematic. This study aims to evaluate taxonomic concepts within Aglaia based on the largest dataset to-date. We analyzed sequences of 237 accessions of Aglaia and representatives of all other genera of the tribe Aglaieae, including nuclear ribosomal ITS, the trnL-trnF intron and intergenic spacer, the atpF intron and the petD region comprising the petB-petD spacer, the petD-5' exon and the petD intron (all but the first from the plastid genome). Our analyses were set both in maximum likelihood and Bayesian frameworks, which (1) supported paraphyly of Aglaia and Aphanamixis; (2) demonstrated polyphyly of previously described sections for Aglaia; and (3) suggested delimitation problems with 57% of the morphologically "variable species" and all "complex species". In general, there were more genetic entities than species described, which shows that the taxonomy of this group is more complex than has sometimes been previously assumed. For some species, morphological variation suggests the existence of more variants, subspecies or species within various taxa. Furthermore, our study detected additional phylogenetic entities that were geographically distinct, occurring on either side of Wallace's Line but not on both sides. The delineation of these inter-specific taxa needs further investigation by taking into account the morphological variation within and between populations across the entire distribution.


Assuntos
Aglaia/classificação , Aglaia/genética , Meliaceae/classificação , Meliaceae/genética , Filogenia , Sudeste Asiático , Sequência de Bases , Teorema de Bayes , DNA de Plantas/genética , DNA Espaçador Ribossômico/genética , Íntrons/genética , Análise de Sequência de DNA
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