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Registros recuperados: 59 | |
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Huysmans, S.; Robbrecht, E.; Smets, E.. |
Recent literature is controversial as regards the segregation of Hallea and Mitragyna, and pretends that the two genera show pollen morphological differences. In the present study the pollen morphology of all ten species of the complex is described on the basis of light and scanning electron microscopy (including examination of broken grains, which were obtained with a technique never applied in palynology, viz. shaking with glass beads). The two genera have 3-zonocolporate grains with compound apertures (endoapertures are always H-shaped, sometimes incompletely so). While Hallea showed to be stenopalynous (sexine always tectate-perforate), Mitragyna is more variable (sexine microreticulate or tectate-perforate), and several of its species have pollen... |
Tipo: Article / Letter to the editor |
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Ano: 1994 |
URL: http://www.repository.naturalis.nl/record/524503 |
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Lens, F.; Jansen, S.; Huysmans, S.; Robbrecht, E.; Smets, E.. |
The Vanguerieae is a large tribe of the subfamily Ixoroideae (Rubiaceae) and consists of about 500 species in 27 genera. This study gives a detailed pollen morphological description of 30 species from 16 genera, based on light microscopy and scanning electron microscopy. The Vanguerieae are considered to be stenopalynous, although there is some evidence to question this. First, there is a difference in sexine types that clearly de® nes Keetia and Psydrax ( both reticulate) , and Canthium and Vanguerieae (both perforate with very small perforations) from the other Vanguerieae investigated. Second, pollen grains corroborate the subgeneric delimitations of Canthium sensu Bridson. Pollen morphologically the tribe is characterised by ( 1) the shape of the... |
Tipo: Article / Letter to the editor |
Palavras-chave: Vanguereae; Ixoroideae; Rubiaceae; Pollen; Morphological variation; Stenopalynous; 42.58. |
Ano: 2000 |
URL: http://www.repository.naturalis.nl/record/423771 |
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Simpson, D.A.; Muthama Muasya, A.; Alves, M.V.; Bruhl, J.J.; Dhooge, S.; Chase, M.W.; Furness, C.A.; Ghamkhar, K.; Goetghebeur, P.; Hodkinson, T.D.; Marchant, A.D.; Reznicek, A.A.; Nieuwborg, R.; Roalson, E.H.; Smets, E.; Starr, J.R.; Thomas, W.W.; Wilson, K.L.; Zhang, X.. |
Since the Monocots II meeting in 1998, significant new data have been published that enhance our systematic knowledge of Cyperaceae. Phylogenetic studies in the family have also progressed steadily. For this study, a parsimony analysis was carried out using all rbcL sequences currently available for Cyperaceae, including data for two new genera. One of the four subfamilies (Caricoideae) and seven of the 14 tribes (Bisboeckelereae, Cariceae, Cryptangieae, Dulichieae, Eleocharideae, Sclerieae, Trilepideae) are monophyletic. Subfamily Mapanioideae and tribe Chrysitricheae are monophyletic if, as the evidence suggests, Hellmuthia is considered a member of Cypereae. Some other features of our analysis include: well-supported Trilepideae and... |
Tipo: Article / Letter to the editor |
Palavras-chave: Cyperaceae; Monocotyledons; Phylogeny; RbcL; Sequence; 42.48. |
Ano: 2007 |
URL: http://www.repository.naturalis.nl/record/414071 |
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Dessein, S.; Harwood, R.; Smets, E.; Robbrecht, E.. |
Complementary to the revision of the genus Spermacoce in the Northern Territory of Australia, pollen morphology of 48 of the 53 native Spermacoce species from the Northern Territory has been investigated by scanning electron and light microscopy. There is considerable variation for most diagnostic pollen characters. The average equatorial diameter (E) ranges from 10.5 to 41.7 μm. Grains are invariably colporate with apertures situated at the equator (being zonocolporate). The number of apertures varies from 3 to 17. The endoaperture is generally an endocingulum, often with a secondary thinning at the ectocolpus; one species has endocolpi. The sexine is usually perforate, but psilate, foveolate, and (micro)reticulate patterns were also found. Supratectal... |
Tipo: Article / Letter to the editor |
Palavras-chave: Spermacoce; Rubiaceae; Pollen morphology; Palynology; Australia; Northern Territory. |
Ano: 2005 |
URL: http://www.repository.naturalis.nl/record/407293 |
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Verellen, J.; Dessein, S.; Razafimandimbison, S.G.; Smets, E.; Huysmans, S.. |
The tribe Naucleeae has recently been recircumscribed on the basis of both morphological and molecular [rbcL, trnT-F, internal transcribed spacer (ITS)] evidence, and has been found to be the sister group of the tribe Hymenodictyeae Razafim. & B. Bremer. In order to find pollen morphological support for this new classification, the pollen and orbicules of 65 species, representing 23 Naucleeae and the two Hymenodictyeae genera, were investigated by scanning electron and light microscopy. Naucleeae pollen is very small (< 20 µm) to small (20–30 µm) and its shape in equatorial view is suboblate to spheroidal or, more rarely, subprolate. Three compound apertures are present, each comprising a long and narrow ectocolpus, a circular to slightly lolongate... |
Tipo: Article / Letter to the editor |
Palavras-chave: Compound apertures; Endoapertures; Orbicule morphology; Palynology; Sexine ornamentation; 42.48. |
Ano: 2007 |
URL: http://www.repository.naturalis.nl/record/422226 |
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Petanidou, T.; Van Laere, A.; Ellis, W.; Smets, E.. |
We studied the amino acid (AA) composition of the floral nectars of 73 plant species occurring in a phryganic (East Mediterranean garrigue) community and investigated whether AA and sugar composition is shaped by evolutionary (plant phylogeny), ecological (flowering time as a direct effect of summer drought) and coevolutionary (pollinator partnership) constraints. Our study utilised an extensive plantpollinator matrix compiled in the same area where the plants had been sampled. Using HPLC we detected 22 AA compounds/groups of compounds, out of which 15 were commonly present in almost all nectars. Among all AAs, phenylalanine was the most abundant, especially in keystone (ââcornucopianââ) plant species visited by many insect species, such as the... |
Tipo: Article / Letter to the editor |
Palavras-chave: Floral nectar; Composition; Mediterranean; Evolution; Ecology; Coeveloution. |
Ano: 2006 |
URL: http://www.repository.naturalis.nl/record/407342 |
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Lens, F.; Dressler, S.; Vinckier, S.; Janssens, S.; Dessein, S.; Van Evelghem, L.; Smets, E.. |
Background and Aims Marcgraviaceae are a rather small family of seven genera and approx. 130 neotropical species. This study aims to present a detailed palynological survey of the family in order to comment on the intrafamily relationships and possible correlations with pollinators. Methods In total, 119 specimens representing 67 species and all genera are observed using light microscopy and scanning electron microscopy. Furthermore, eight species from five genera are studied with transmission electron microscopy. Key Results Our results show that pollen grains of Marcgraviaceae are small (20–35 mm), have three equatorial apertures, granules on the colpus membrane, oblate spheroidal to prolate spheroidal shapes, mainly psilate to perforate ornamentations,... |
Tipo: Article / Letter to the editor |
Palavras-chave: Balsaminoids; Ericales; Marcgraviaceae; Neotropics; Orbicules; Palynology; SEM; TEM. |
Ano: 2005 |
URL: http://www.repository.naturalis.nl/record/407283 |
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Groeninckx, I.; Janssens, S.; Smets, E.; Verstraete, B.. |
Astiella is an herbaceous genus endemic to Madagascar, originally described with a single species A. delicatula Jovet. Molecular and morphological evidence place it in the tribe Spermacoceae s. lat. of Rubiaceae. During herbarium studies and fieldwork in Madagascar, 11 new Astiella species were identified and these are described here: A. antongilensis Groeninckx sp. nov., A. antsalovansis Groeninckx sp. nov., A. confusa Groeninckx sp. nov., A. deblockiae Groeninckx sp. nov., A. desseinii Groeninckx sp. nov., A. homolleae Groeninckx sp. nov., A. latifolia Groeninckx sp. nov., A. longifimbria Groeninckx sp. nov., A. perrieri Groeninckx sp. nov., A. pulla Groeninckx sp. nov., and A. tsaratanensis Groeninckx sp. nov. The genus Astiella now holds 12 species in... |
Tipo: Article / Letter to the editor |
Palavras-chave: Astiella; Endemism; Madagascar; Rubiaceae; Spermacoceae s. lat.. |
Ano: 2017 |
URL: http://www.repository.naturalis.nl/record/629097 |
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Janssens, S.; Lens, F.; Dressler, S.; Geuten, K.; Smets, E.; Vinckier, S.. |
Background and Aims The objective of this study is to examine the palynological diversity of Balsaminaceae (two genera/61000 species), Tetrameristaceae (two genera/two species) and Pellicieraceae (one genus/one species). The diversity found will be used to infer the systematic value of pollen features within the balsaminoid clade. Methods Pollen morphology and ultrastructure of 29 species, representing all families of the balsaminoid clade except Marcgraviaceae, are investigated by means of light microscopy, scanning electron microscopy and transmission electron microscopy. Key Results Balsaminaceae pollen is small to medium sized with three to four apertures, which can be either colpate or porate, and a sexine sculpturing varying from coarsely... |
Tipo: Article / Letter to the editor |
Palavras-chave: Balsaminaceae; Ericales; Orbicules; Pellicieraceae; Pollen; SEM; TEM; Tetrameristaceae. |
Ano: 2005 |
URL: http://www.repository.naturalis.nl/record/407278 |
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Lens, F.; Jansen, S.; Caris, P.; Serlet, L.; Smets, E.. |
The wood structure of 78 species from 27 genera representing the woody primuloids (Maesaceae, Myrsinaceae, and Theophrastaceae) was investigated using light microscopy (LM) and scanning electron microscopy (SEM). Results indicated that the ray structure, the nature of mineral inclusions, and the occurrence of breakdown areas in rays can be used to separate the three primuloid families from each other. Within Ericales, the presence of exclusively multiseriate rays is synapomorphic for Myrsinaceae and Theophrastaceae, and the occurrence of breakdown areas in rays is synapomorphic for Myrsinaceae. Within Myrsinaceae, the wood structure of the mangrove genus Aegiceras differs because it has short vessel elements that are storied, non-septate fibers, a... |
Tipo: Article / Letter to the editor |
Palavras-chave: Primuloids; Ericales s.l.; Maesaceae; Myrsinaceae; Theophrastaceae; Wood anatomy; Comparison; Light microscopy; Scanning electron microscopy. |
Ano: 2005 |
URL: http://www.repository.naturalis.nl/record/407307 |
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Hamann, T.; Smets, E.; Lens, F.. |
Bark anatomy is an unappreciated discipline in plant systematics, despite its great potential to reveal systematically informative features. In this paper, main reasons for the lack of detailed bark anatomical data in many plant families are identified, including problems with sectioning, terminological issues, and difficulties in observation of dilated stems. We deal with these problems by focusing on two aspects: (1) compare, discuss and improve existing sectioning and maceration techniques using two species with soft and hard bark tissues; and (2) discuss the best way to collect stem bark samples. We hope that this paper will stimulate inclusion of bark anatomical data in future systematic studies. |
Tipo: Article / Letter to the editor |
Palavras-chave: Bark anatomy; Light microscopy; Macerations; Plant systematics; Phloem; Sectioning; 42.54. |
Ano: 2011 |
URL: http://www.repository.naturalis.nl/record/421834 |
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Vrijdaghs, H.; Goetghebeur, P.; Muasya, A.M.; Caris, P.; Smets, E.. |
! Background and Aims The generic delimitations of Ficinia and Isolepis, sister genera in the Cypereae, are blurred. Typical Ficinia flowers have a lobed gynophore, which envelops the base of the nutlet, whereas in Isolepis the character is considered to be absent. Some former species of Isolepis, lacking the gynophore, were recently included in Ficinia. The floral ontogeny of representative taxa in Ficinia and Isolepis were investigated with the aim of evaluating the origin and nature of the gynophore in the Cypereae. ! Methods The spikelet and floral ontogeny in inflorescences collected in the field was investigated using scanning electron microscopy (SEM) and light microscopy (LM). ! Key Results SEM images of Isolepis setacea and I. antarctica, Ficinia... |
Tipo: Article / Letter to the editor |
Palavras-chave: Ficinia; Floral ontogeny; Gynophore; Isolepis; Scanning electron microscopy. |
Ano: 2005 |
URL: http://www.repository.naturalis.nl/record/407286 |
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Jansen, S.; Watanabe, T.; Caris, P.; Geuten, K.; Lens, F.; Pyck, N.; Smets, E.. |
The distribution of aluminium (Al) accumulation in the Ericales is surveyed, based on semi-quantitative tests of 114 species and literature data. Al accumulation mainly characterises the families Diapensiaceae, Pentaphylacaceae, Symplocaceae, Ternstroemiaceae, and Theaceae. Al accumulation is consistently present or absent in most families examined, but the character appears to be more variable in a few taxa (e.g., Lecythidaceae, Myrsinaceae). Although the interfamilial relationships within the Ericales require further research, the ability to accumulate high levels of Al appears to show considerable taxonomic significance. While the majority of Al accumulating Ericales includes woody, tropical plants, the feature is remarkably present in several... |
Tipo: Article / Letter to the editor |
Palavras-chave: Aluminium accumulation; Ericales; Phyogeny; Diapensiaceae; Pentaphylacaceae; Symplocaceae; Ternstroemiaceae; Theaceae; 42.56. |
Ano: 2004 |
URL: http://www.repository.naturalis.nl/record/431739 |
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Lens, F.; Gasson, P.; Smets, E.; Jansen, S.. |
The wood anatomy of 16 of the 37 genera within the epacrids (Styphelioideae, Ericaceae s.l.) is investigated by light and scanning electron microscopy. Several features in the secondary xylem occur consistently at the tribal level: arrangement of vessel‐ray pits, distribution of axial parenchyma, ray width, and the presence and location of crystals. The primitive nature of Prionoteae and Archerieae is supported by the presence of scalariform perforation plates with many bars and scalariform to opposite vessel pitting. The wood structure of Oligarrheneae is similar to that of Styphelieae, but the very narrow vessel elements, exclusively uniseriate rays and the lack of prismatic crystals in Oligarrheneae distinguish these two tribes. The secondary xylem of... |
Tipo: Article / Letter to the editor |
Palavras-chave: Ecological wood anatomy; Epacrids; Ericaceae s.l.; Styphelioideae; Systematic wood anatomy; 42.56. |
Ano: 2003 |
URL: http://www.repository.naturalis.nl/record/431740 |
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Registros recuperados: 59 | |
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