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Kenneth J. Sytsma - One of the best experts on this subject based on the ideXlab platform.
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Summary of major relationships within Myrtales.
2017Co-Authors: Ricardo Kriebel, Mohammad Khabbazian, Kenneth J. SytsmaAbstract:Major relationships within Myrtales showing three possible placements of Combretaceae (summarized in [39]). A: Phylogeny with the family Combretaceae sister to the rest of the order. B: Phylogeny with the family Combretaceae sister to Lythraceae + Onagraceae. C: Phylogeny with the family Combretaceae as sister to rest of the order excluding Lythraceae + Onagraceae.
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Examples of pollen grains in Myrtales.
2017Co-Authors: Ricardo Kriebel, Mohammad Khabbazian, Kenneth J. SytsmaAbstract:Scanning electron micrographs of pollen grains from selected species of Myrtales. Representing the CAP clade is Saltera sarcocolla; Bucida macrostachya in equatorial view and Conocarpus erecta in polar view (Combretaceae); Heimia salicifolia (Lythraceae); Miconia alypifolia in equatorial view and Miconia caesia in polar view for (Melastomaceae); Tristania conferta (Myrtaceae); Calylophus toumeyi (Onagraceae). Scale bars are 5 um except for Onagraceae which is 50 um. Adapted from [50] with permission from the Annals of the Missouri Botanical Garden Press.
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A continuous morphological approach to study the evolution of pollen in a phylogenetic context: An example with the order Myrtales
2017Co-Authors: Ricardo Kriebel, Mohammad Khabbazian, Kenneth J. SytsmaAbstract:The study of pollen morphology has historically allowed evolutionary biologists to assess phylogenetic relationships among Angiosperms, as well as to better understand the fossil record. During this process, pollen has mainly been studied by discretizing some of its main characteristics such as size, shape, and exine ornamentation. One large plant clade in which pollen has been used this way for phylogenetic inference and character mapping is the order Myrtales, composed by the small families Alzateaceae, Crypteroniaceae, and Penaeaceae (collectively the “CAP clade”), as well as the large families Combretaceae, Lythraceae, Melastomataceae, Myrtaceae, Onagraceae and Vochysiaceae. In this study, we present a novel way to study pollen evolution by using quantitative size and shape variables. We use morphometric and morphospace methods to evaluate pollen change in the order Myrtales using a time-calibrated, supermatrix phylogeny. We then test for conservatism, divergence, and morphological convergence of pollen and for correlation between the latitudinal gradient and pollen size and shape. To obtain an estimate of shape, Myrtales pollen images were extracted from the literature, and their outlines analyzed using elliptic Fourier methods. Shape and size variables were then analyzed in a phylogenetic framework under an Ornstein-Uhlenbeck process to test for shifts in size and shape during the evolutionary history of Myrtales. Few shifts in Myrtales pollen morphology were found which indicates morphological conservatism. Heterocolpate, small pollen is ancestral with largest pollen in Onagraceae. Convergent shifts in shape but not size occurred in Myrtaceae and Onagraceae and are correlated to shifts in latitude and biogeography. A quantitative approach was applied for the first time to examine pollen evolution across a large time scale. Using phylogenetic based morphometrics and an OU process, hypotheses of pollen size and shape were tested across Myrtales. Convergent pollen shifts and position in the latitudinal gradient support the selective role of harmomegathy, the mechanism by which pollen grains accommodate their volume in response to water loss.
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Paraphyly in Tribe Onagreae: Insights into Phylogenetic Relationships of Onagraceae Based on Nuclear and Chloroplast Sequence Data
Systematic Botany, 2004Co-Authors: Rachel A. Levin, Warren L. Wagner, Peter C. Hoch, Elizabeth A. Zimmer, William J. Hahn, Aarón Rodríguez, David A. Baum, Liliana Katinas, Kenneth J. SytsmaAbstract:Onagraceae are a family of 17 genera in seven tribes, with the majority of species in tribes Onagreae and Epilobieae. Despite the species-richness of these two tribes, to date no phylogenetic study has been done with sufe cient taxon sampling to examine relationships between and within these tribes. In this study, we used DNA sequence data from one nuclear region (ITS) and two chloroplast regions ( trnL-trnF and rps16) to infer phylogenetic relationships among93taxa across thefamily, withconcentratedsamplinginthelargetribeOnagreae.Results stronglysuggestthattribeGongylocarpeae is sister to tribes Epilobieae 1 Onagreae, both of which are monophyletic. Within Onagreae, Camissonia seems to be broadly paraphyletic, and Oenothera is also paraphyletic. In Oenothera there appear to be two lineages, one of which has Gaura 1 Stenosiphon nested within it. At the base of the Onagraceae phylogeny, we have clarie ed previous confusion regarding cone icting placements of Hauya and Lopezia based on nuclear versus chloroplast data. Results of theseanalysesaresupported by morphology and suggest the need for new taxonomic delimitations, which are forthcoming.
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Family‐level relationships of Onagraceae based on chloroplast rbcL and ndhF data
American Journal of Botany, 2003Co-Authors: Rachel A. Levin, Warren L. Wagner, Peter C. Hoch, Molly Nepokroeff, J. Chris Pires, Elizabeth A. Zimmer, Kenneth J. SytsmaAbstract:Despite intensive morphological and molecular studies of Onagraceae, relationships within the family are not fully understood. One drawback of previous analyses is limited sampling within the large tribe Onagreae. In addition, the monophyly of two species-rich genera in Onagreae, Camissonia and Oenothera, has never been adequately tested. To understand relationships within Onagraceae, test the monophyly of these two genera, and ascertain the affinities of the newly discovered genus Megacorax, we conducted parsimony and maximum likelihood analyses with rbcL and ndhF sequence data for 24 taxa representing all 17 Onagraceae genera and two outgroup Lythraceae. Results strongly support a monophyletic Onagraceae, with Ludwigia as the basal lineage and a sister-taxon relationship between Megacorax and Lopezia. Gongylocarpus is supported as sister to Epilobieae plus the rest of Onagreae, although relationships within the latter clade have limited resolution. Thus, we advocate placement of Gongylocarpus in a monogeneric tribe, Gongylocarpeae. Most relationships within Onagreae are weakly resolved, suggesting a rapid diversification of this group in western North America. Neither Camissonia nor Oenothera appears to be monophyletic; however, increased taxon sampling is needed to clarify those relationships. Morphological characters generally agree with the molecular data, providing further support for relationships.
Buril, Maria Teresa - One of the best experts on this subject based on the ideXlab platform.
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Flora da Usina São José, Igarassu, Pernambuco (Brasil): Lythraceae J. St.-Hil. e Onagraceae Juss.
'Acta Brasiliensis', 2020Co-Authors: Lacerda, Tainá Lacerda Gomes, Rocha, Amanda Macêdo, Buril, Maria TeresaAbstract:Lythraceae comprises about 30 genera and 600 species widely distributed in tropical and subtropical regions, while Onagraceae comprises 22 genera and about 660 species distributed in temperate and subtropical areas, predominantly in Americas. The aim of this work was to realize the taxonomic study of Lythraceae and Onagraceae species from Usina São José, Igarassu, Pernambuco (Brazil), an Atlantic forest remnant. Fieldworks and visits to herbaria HST, HUEFS, IPA, JPB, PEUFR and UFP were conducted between 2018 and 2019. Three Lythraceae species were recognized: Cuphea carthagenensis (Jacq.) J.F. Macbr., C. flava Spreg. and Rotala ramosior (L.) Koehne, and three Onagraceae species: Ludwigia erecta (L.) H. Hara, L. hyssopifolia (G. Don) Exell and L. octovalvis (Jacq.) P.H. Raven. Rotala ramosior is a new record for Brazil. Morphological descriptions, an identification key, phenological period, geographic distribution, taxonomic notes, photographs and illustrations of diagnostic characters are presented herein. The relevant morphological characters for species identification are phyllotaxy, indumentum of stems, shape and indumentum of leaves, petals color and apex, capsule shape, seeds arrangement and raphe size.Lythraceae apresenta cerca de 30 gêneros e 600 espécies amplamente distribuídas nas regiões tropicais e subtropicais, enquanto Onagraceae compreende 22 gêneros e cerca de 660 espécies distribuídas nas regiões temperadas e subtropicais, predominantemente nas Américas. Este trabalho teve como objetivo realizar o estudo taxonômico das espécies de Lythraceae e Onagraceae ocorrentes na Usina São José, Igarassu, Pernambuco (Brasil), um remanescente de Mata Atlântica. Para isso, foram realizadas expedições de campo e visitas aos herbários HST, HUEFS, IPA, JPB, PEUFR e UFP entre 2018 e 2019. Foram reconhecidas três espécies de Lythraceae: Cuphea carthagenensis (Jacq.) J.F. Macbr., C. flava Spreg. e Rotala ramosior (L.) Koehne, e três espécies de Onagraceae: Ludwigia erecta (L.) H. Hara, L. hyssopifolia (G. Don) Exell e L. octovalvis (Jacq.) P.H. Raven. Rotala ramosior é um novo registro para a flora do Brasil. Descrições morfológicas, uma chave de identificação, período fenológico, distribuição geográfica, notas taxonômicas, pranchas de fotografias e ilustrações dos caracteres diagnósticos são apresentadas. Os caracteres morfológicos relevantes para a identificação das espécies são filotaxia, indumento dos ramos, forma e indumento das folhas e cor e ápice das pétalas, forma da cápsula, arranjo das sementes e tamanho da rafe
Грошенко С.А. - One of the best experts on this subject based on the ideXlab platform.
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Особенности распространения и инвазионный потенциал видов рода Oenothera L. (subsect. Oenothera, Onagraceae) в Восточной Европе
Тверской государственный университет, 2020Co-Authors: Тохтарь В.К., Грошенко С.А.Abstract:Изучение гербарного материала видов рода Oenothera L. (subsect. Oenothera, Onagraceae) в коллекциях LE, MW, MHA, MOSP, BSU, RV, KW, DNZ, полевые исследования, а также анализ основных публикаций по теме исследования позволили выявить характерные особенности распространения энотер. Сравнительный анализ современных ареалов видов свидетельствует о том, что среднецветковые виды в наибольшей степени приспособлены к климатическим различиям в Западной и Восточной Европе, обладают широкой экологической амплитудой и, поэтому, являются наиболее распространенными растениями. На основании изученных гербарных экземпляров энотер, собранных в Восточной Европе, установлен инвазионный потенциал видов, определены лимитирующие значения климатических факторов для наиболее инвазионных видов, представлены основные характеристики климатических ареалов видо
Maria Teresa Buril - One of the best experts on this subject based on the ideXlab platform.
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Flora of Usina São José, Igarassu, Pernambuco (Brazil): Lythraceae J. St.-Hil. and Onagraceae Juss
Acta Brasiliensis, 2020Co-Authors: Tainá Lacerda Gomes Lacerda, Amanda Macêdo Rocha, Maria Teresa BurilAbstract:Lythraceae comprises about 30 genera and 600 species widely distributed in tropical and subtropical regions, while Onagraceae comprises 22 genera and about 660 species distributed in temperate and subtropical areas, predominantly in Americas. The aim of this work was to realize the taxonomic study of Lythraceae and Onagraceae species from Usina Sao Jose, Igarassu, Pernambuco (Brazil), an Atlantic forest remnant. Fieldworks and visits to herbaria HST, HUEFS, IPA, JPB, PEUFR and UFP were conducted between 2018 and 2019. Three Lythraceae species were recognized: Cuphea carthagenensis (Jacq.) J.F. Macbr., C. flava Spreg. and Rotala ramosior (L.) Koehne, and three Onagraceae species: Ludwigia erecta (L.) H. Hara, L. hyssopifolia (G. Don) Exell and L. octovalvis (Jacq.) P.H. Raven. Rotala ramosior is a new record for Brazil. Morphological descriptions, an identification key, phenological period, geographic distribution, taxonomic notes, photographs and illustrations of diagnostic characters are presented herein. The relevant morphological characters for species identification are phyllotaxy, indumentum of stems, shape and indumentum of leaves, petals color and apex, capsule shape, seeds arrangement and raphe size.
Dallas C. Mildenhall - One of the best experts on this subject based on the ideXlab platform.
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A fossil Fuchsia (Onagraceae) flower and an anther mass with in situ pollen from the early Miocene of New Zealand
American Journal of Botany, 2013Co-Authors: Daphne E. Lee, John G. Conran, Jennifer M. Bannister, Uwe Kaulfuss, Dallas C. MildenhallAbstract: Premise of the study: Fuchsia (Onagraceae) anthers, pollen, and an ornithophilous Fuchsia -like fl ower from an earliest Miocene lacustrine diatomite deposit at Foulden Maar, southern New Zealand confi rm a long record for Fuchsia in New Zealand and probably an equally long history for its distinctive honeyeater pollination syndrome. The anthers contain in situ pollen of the fossil palynomorph previously assigned to Diporites aspis Pocknall et Mildenh. (Onagraceae: Fuchsia L.). Methods: We undertook comparative studies of the fl ower and anther morphology of the newly discovered macrofossils and compared the in situ pollen grains from the anthers with dispersed pollen grains from extant species. Key results: The anther mass is referred to a new, extinct species, Fuchsia antiqua D.E.Lee, Conran, Bannister, U.Kaulfuss & Mildenh. (Onagraceae), and is associated with a fossilized Fuchsia -like fl ower from the same small mining pit. Because Diporites van der Hammen is typifi ed by a fungal sporomorph, the replacement name for D. aspis is Koninidites aspis (Pocknall & Mildenh.) Mildenh. gen. & comb. nov. Phylogenetic placement of the fossils agrees with a proximal position to either sect. Skinnera or sect. Procumbentes. These are the oldest macrofossils of Fuchsia globally. Conclusions: The fl oral structures are remarkably similar to those of modern New Zealand Fuchsia . They suggest that the distinctive honeyeater bird-pollination syndrome/association seen in modern New Zealand was already established by the late Oligocene–earliest Miocene. The implications for the biogeography and paleoecology of Fuchsia in Australasia are discussed.
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New Zealand Eocene, Oligocene and Miocene Macrofossil and Pollen Records and Modern Plant Distributions in the Southern Hemisphere
The Botanical Review, 2012Co-Authors: John G. Conran, Jennifer M. Bannister, Jon K. Lindqvist, Dallas C. MildenhallAbstract:The modern New Zealand flora has a relatively low number of families and genera in relation to land area, but well-preserved macrofossils and pollen from three sites in southern New Zealand suggest that the floras in Eocene, Oligocene and Miocene times were much more diverse at the generic level. At Pikopiko, Southland, a late Eocene in situ forest with fern understory was dominated by conifers, Casuarinaceae, Lauraceae, Nothofagus , Proteaceae, and mesothermal angiosperms including palms (aff. Calamus ), Sapindaceae: Cupaniae and Picrodendraceae. At Newvale Mine, Southland, a leaf bed within a thick lignite seam represents leaf fossils preserved in a late Oligocene oligotrophic bog. This site demonstrates that Agathis , Dacrycarpus , Dacrydium , Halocarpus , Microcachrys , Podocarpus and Phyllocladus coexisted with diverse angiosperms including Nothofagus , Gymnostoma , Cunoniaceae, Ericaceae, Sapindaceae and several Proteaceae. Pollen data add Meliaceae, Myrtaceae, Onagraceae and Rubiaceae to the flora . At Foulden Maar, Otago, mummified leaves and flowers, including several with in situ pollen, demonstrate the existence of a diverse flora surrounding an Early Miocene lake. This site contains numerous monocot macrofossils including Astelia , Cordyline , Ripogonum and Typha , as well as the oldest fossils known for Orchidaceae and Luzuriagaceae. This flora was dominated by Lauraceae with affinities to Cryptocarya and Litsea , but other families include Araliaceae, Cunoniaceae, Elaeocarpaceae, Euphorbiaceae sensu lato, Menispermaceae, Myrsinaceae, Myrtaceae, Onagraceae, Proteaceae and Sterculiaceae. Many ferns, conifers, and Nothofagus are from lineages with Gondwanan ancestors, whereas other taxa show links to Australia (e.g., Gyrostemonaceae), New Caledonia (e.g., Beauprea ) and South America (e.g., Luzuriaga, Fuchsia ). Many of these taxa are now extinct in New Zealand, and therefore indicate much wider biogeographic ranges for many families and genera in the past.
