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| Registros recuperados: 30 | |
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| Reenen, G.B.A. van; Gradstein, S.R.. |
| Along an altitudinal transect on the northern slope of the Sierra Nevada de Santa Marta, Colombia, 500-4100 m, five altitudinal bryophyte zones are distinguished – four forest zones and one páramo zone – based on ecosystem relevé analysis concerning species presence, substrate preference and percentage cover of bryophytes. Relevés were compared by using Sørensen’s Index of Similarity and a simplified dendrogram technique, and zonation diagrams were constructed. Bryophyte zonation seems primarily correlated with climatic factors (precipitation, air temperature) as preliminary data suggest. Species presence and cover percentage appear to be of almost equal significance in distinguishing the different bryophyte zones of the tropical forests and are highest in... |
| Tipo: Article / Letter to the editor |
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| Ano: 1983 |
URL: http://www.repository.naturalis.nl/record/534779 |
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| Gradstein, S.R.; Pócs, T.; Váňa, J.. |
| An increasingly large number of macrodisjunct species is emerging from recent literature dealing with taxonomy and floristics of tropical bryophytes. This paper reviews present knowledge concerning Afro-American disjunctions in Hepaticae and seeks to interprete the data in the light of current phytogeographical theory. Numerous new floristic records and range extensions are given and some taxonomic novelties are proposed. For 35 Afro-American species known three main distribution types are recognized, each further subdivided: Tropical Afro-American (lowland, montane and the alpine element), Subtropical-Mediterranean (southern, wide element) and Temperate-Subantarctic (southern, wide element). Most species belong to Jungermanniales except for the... |
| Tipo: Article / Letter to the editor |
Palavras-chave: Africa; America; Disjunction; Dispersal; Hepaticae; Plate tectonics; Phytogeography.; Taxonomy; Vicariants. |
| Ano: 1983 |
URL: http://www.repository.naturalis.nl/record/535250 |
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| Gradstein, S.R.. |
| Lejeuneaceae include species with or without underleaves. Those with underleaves (the majority) have traditionally been classified (e.g. Spruce 1884) into “Lejeuneaceae Holostipae” (underleaves undivided) and “Lejeuneaceae Schizostipae” (underleaves bifid). This system has now become obsolete and has been replaced by a more natural classification into subfamilies, based on several gametophytic as well as sporophytic characters (Schuster 1984, Grolle 1983). The current subfamily system of Lejeuneaceae is shown in Table I, which also lists the genera containing holostipous species. From this table it becomes apparent that holostipous Lejeuneaceae are a clearly unnatural, polyphyletic group, comprising taxa of 5 different subfamilies. Two subfamilies and 34... |
| Tipo: Article / Letter to the editor |
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| Ano: 1985 |
URL: http://www.repository.naturalis.nl/record/535186 |
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| Gradstein, S.R.; Reenen, G.B.A. van; Griffin, D.. |
| Based on data from the ECOANDES project, a phytogeographical analysis has been made of the bryophyte flora along the wet, foggy western slope (1000-4500 m) and the drier eastern slope (500-4500 m) of the Colombian Central Cordillera at the ‘Parque de los Nevados’. Species richness increases with altitude to the upper montane forest, which holds the largest diversity. Liverworts outnumber mosses in the upper submontane and montane forests on the western slope, but elsewhere, in drier environments, their number is lower and falls to below that of mosses. Furthermore, it appears that at lower altitudes, below 3000 m, wide-ranging tropical species prevail whereas narrowranging tropical species (andean and endemic element) and species of temperate origin are... |
| Tipo: Article / Letter to the editor |
Palavras-chave: Phytogeography; Species richness; Altitudinal zonation; Andes; Bryophytes. |
| Ano: 1988 |
URL: http://www.repository.naturalis.nl/record/535268 |
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| Keßler, P.J.A.; Bos, M.M.; Sierra Daza, S.E.C.; Kop, A.; Willemse, L.P.M.; Pitopang, R.; Gradstein, S.R.. |
| Sulawesi comprises of about 182,870 km² of land and fewer botanical specimens (about 23 specimens per 100 km², Whitten et al., 1987) have been collected here than in any other major island in Indonesia. This island is up to date botanically poorly explored and according to Van Steenis (1950) about 32,500 specimens of plants were recorded, the number is probably only a rough estimation and certainly in the precomputer era not based on real specimens. Within the framework of STORMA (Stability of Rainforest Margins) we analyzed the vegetation in several plots of one hectare of different land use systems at the Lore Lindu National Park, Central Sulawesi, Indonesia. Rapidly we were faced with the problem that the identification of the mostly sterile trees would... |
| Tipo: Article / Letter to the editor |
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| Ano: 2002 |
URL: http://www.repository.naturalis.nl/record/526385 |
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| Gradstein, S.R.. |
| The new checklist of Dutch liverworts comprises 126 species, 1 subspecies and 5 varieties. Since 1962 seven liverwort species have been added to the flora: Barbilophozia hatcheri, Calypogeia muellerana, Cephalozia pleniceps, Fossombronia incurva, Haplomitrium hookeri, Lophozia perssonii and Plagiochila porelloides. Of twelve species presumed occurrence in the Netherlands needs verification. Nomenclature follows Grolle’s “Verzeichnis der Lebermoose Europas” (Feddes Repert. 87: 171-279. 1976), except for Isopaches, Leiocolea and Microlejeunea, which are maintained as genera and Phaeoceros carolinianus, Cephalozia lammersiana, Chiloscyphus pallescens, Lophozia silvicola and Lophocolea cuspidata. , which are treated as intraspecific taxa. |
| Tipo: Article / Letter to the editor |
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| Ano: 1977 |
URL: http://www.repository.naturalis.nl/record/534876 |
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| Gradstein, S.R.. |
| Caudalejeunea grolleana Gradst. spec. nov. from Madagascar is referred to this genus with some doubt because of the absence of gemmiparous branches. Ptychocoleus cristilobus (Steph.) Steph. from S. E. Asia has gemmiparous branches and therefore is a true Caudalejeunea: C. cristiloba (Steph.) comb. nov. This species is remarkable by its complicated ciliate leaflobule and by its polystratose rhizoid-disc. Two subspecies are distinguished: ssp. cristiloba from Burma, Andaman Is., Thailand, and Singapore, and ssp. samoana (Steph.) comb. nov. (Caudalejeunea samoana Steph.) from Samoa. Both C. grolleana and C. cristiloba have a 4-5-carinate perianth, which shows that the trigonous perianth present in most species of Caudalejeunea is not a stable character of... |
| Tipo: Article / Letter to the editor |
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| Ano: 1974 |
URL: http://www.repository.naturalis.nl/record/534878 |
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| Gradstein, S.R.. |
| The new Amazonian liverwort genus Verdoornianthus is considered to be a specialized derivative of the widespread tropical genus Archilejeunea. Differences are the absence of innovations, the dull, suberect leaves, the tristratose rhizoid pad and the larger size of the lobule of the female bracts in Verdoornianthus. There are two species, V. marsupiifolius (Spruce) comb. nov. (Lejeunea marsupiifolia Spruce) from the upstream part of the Rio Negro and V. griffinii sp. nov. from Manaus. |
| Tipo: Article / Letter to the editor |
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| Ano: 1977 |
URL: http://www.repository.naturalis.nl/record/534767 |
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| Gradstein, S.R.; Cleef, A.M.; Fulford, M.H.. |
| This paper is the second (Florschütz & Florschütz-de Waard 1974) in the series of reports on cryptogams of Colombia, especially the high Andean bryophytes and lichens, in the framework of recent phytosociological and ecological studies in the area by A. M. Cleef and T. van der Hammen (Amsterdam) and his collaborators. The aim of these studies is to prepare comprehensive descriptions of the various Andean biota of Colombia as a basis for an evaluation of the biological diversity of the Andean environment of Colombia. This paper deals with the Hepaticae or liverworts and focuses on the structure of the oil bodies in the liverwort cell and the geographical and ecological distribution of the species. There are few papers on tropical Andean liverworts. The... |
| Tipo: Article / Letter to the editor |
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| Ano: 1977 |
URL: http://www.repository.naturalis.nl/record/535100 |
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| Gradstein, S.R.; Weber, William A.. |
| De las Islas Galápagos se conoce más de 200 especies de briófitas (el número total de los musgos y de las hepáticas es de mas o menos igual). Más que 2/3 partes de las especies occurren en la selva y matorrales perennifolias y húmedas limitadas a las zonas altas de algunas islas. Una proporción elevada (65-70%) de la brioflora trata de especies de una distribución amplia y neotropical o ampliamente tropical, que probablemente han llegado cón los vientos predominantes orientales del continente sudamericano. Generalmente las briófitas de las Islas Galápagos tienen una dispersión excelente, al contrario de otros grupos de organismos. Mas o menos 85% de las hepáticas produce esperes y/o gemmae y aproximadamente 40% de las especies son bisexuales. Además es... |
| Tipo: Article / Letter to the editor |
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| Ano: 1982 |
URL: http://www.repository.naturalis.nl/record/535016 |
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| Gradstein, S.R.; Asakawa, Y.; Mues, R.; Klein, R.. |
| Chemical analysis of representatives of about thirty genera of Lejeuneaceae has shown that the terpenoid and flavonoid content of the Lejeuneaceae is basically comparable to that of other Hepaticae and quite diversified. Among the terpenoids detected, some are common throughout the family (elemenenes, germacrenes), others are distributed more restrictedly and are indicative of evolutionary relationships among genera, e.g. borneols (Nipponolejeunea), pinguisanines (Acrolejeunea complex), striatenes (Ptychanthoideae, Omphalanthus complex), calamenanes ( Lopholejeunea) and labdanes (Ptychanthus, Tuzibeanthus). Flavonoids are present in smaller amounts than terpenoids and comprise some compounds unique to bryophytes (lutonarin, kaempferol-3-methylether). The... |
| Tipo: Article / Letter to the editor |
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| Ano: 1985 |
URL: http://www.repository.naturalis.nl/record/535244 |
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| Gradstein, S.R.; Held, J.J. den; Wolff, P.. |
| Revision of the Dutch species of the Bryum crythrocarpum complex. A revision is given of the collections of the Brya erythrocarpa from Holland. Delimitating the species of this group the authors have followed the monograph of the European Brya erythrocarpa by Crundwell & Nyholm (1964). 5 species have been found in Holland up till now: Bryum micro-eryithrocarpum C. MÜLL. & KINDB., B. radiculosum Brid,. B. klinggraeffii Schimp., B. violaceum Crundw. & Nyholm and B. ruderale Crundw. & Nyholm. The latter three have not been collected until 1968, B. violaceum and B. ruderale being recorded here for the first time from our country. These two species were discovered in the Southern part of the province of Limburg, a hilly area with rich,... |
| Tipo: Article / Letter to the editor |
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| Ano: 1971 |
URL: http://www.repository.naturalis.nl/record/534893 |
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| Gradstein, S.R.. |
| A characteristic feature of the liverwort cell is the presence of “oil bodies”. Chemically they are made up of rather volatile terpenoids, mainly sesquiterpenes and their derivatives (Suire 1975) which seem to be surrounded by a membrane. The nature of this membrane is still unknown. Through the light microscope the oil bodies appear as colourless, rarely brownish or blueish organelles in the cytoplasm, showing great variation in shape, size, number and structure. The morphological characteristics of the oil bodies, which have been studied over 80% of the genera of Hepaticae, have been shown to be taxonomically significant (cf. Schuster 1966). While in the subclass Marchantiidae they are restricted to special, chloroplast-free “oil cells” of the... |
| Tipo: Article / Letter to the editor |
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| Ano: 1978 |
URL: http://www.repository.naturalis.nl/record/535050 |
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| Gradstein, S.R.. |
| This report deals with the results of the determination of bryophytes collected by the author in 1967 in the western District of Chanià on the island of Crete. 33 species new to Crete were discovered and a number of bryophytes were collected for the first time in the District Chanià. Some species listed here were previously known from only very few European localities: Riella notarisii, Solenostoma handelii, Rhamphidium rechingeri and Trematodon longicollis. Rhamphidium rechingeri has been found to be conspecific with the west-mediterranean Rhamphidium purpuratum Michx. A few remarks are made on the distribution of the bryophytes on the island. A relatively rich flora of liverworts is present in District Chanià, which is due to a high annual... |
| Tipo: Article / Letter to the editor |
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| Ano: 1971 |
URL: http://www.repository.naturalis.nl/record/534726 |
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| Gradstein, S.R.. |
| A small set of bryophytes collected on the islands of Malta and Gozo in April-May, 1968, and April, 1969, by K. U. Kramer and L. Y. Th. Westra (Utrecht) was handed to the author for identification. The results are presented here as a supplement to a paper on the vascular plants of the Maltese islands (Kramer et al. 1972). The collections are deposited in the herbarium of the State University of Utrecht. In the past few years many new data have been published on the bryophytes of the Mediterranean islands, cf. Sunding (1967,1971), Koppe (1965), Lübenau & Lübenau (1970), Düll (1967), Gradstein (1971), and Townsend (1965). The liverwort flora of the Mediterranean coasts is being studied thoroughly by Jovet-Ast & Bischler (cf. 1968). Yet the bryophyte... |
| Tipo: Article / Letter to the editor |
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| Ano: 1972 |
URL: http://www.repository.naturalis.nl/record/534794 |
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| Gradstein, S.R.; Sipman, H.J.M.. |
| Campylopus introflexus (Hedw.) Brid. sensu lato comprises two widespread, closely related species: tropical and warm-temperate C. pilifer Brid. (= C. polytrichoides DeNot.) and temperate southern hemispheric C. introflexus (Hedw.) Brid., which was recently introduced in Europe. Main differences are in the height of the dorsal lamellae of the leaves, in spore size and in seta length. In C. pilifer lamellae are more pronounced in tropical mountains than in lowland areas. An extreme form with lamellae up to seven cells high is C. pilifer var. lamellatus (Mont.) comb. nov. from Bolivia. |
| Tipo: Article / Letter to the editor |
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| Ano: 1978 |
URL: http://www.repository.naturalis.nl/record/535057 |
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| Gradstein, S.R.; Cleef, A.M.; Fulford, M.H.. |
| Oil bodies in leaves variable in number, (2-)3-8(-13) per cell; subglobose to, more rarely, ellipsoid, 4-8(-12)x4—6 μm; colourless, rather coarsely to finely granulosepapillose, becoming homogeneous upon degeneration (Colombia, Cundinamarca, Cleef 78b, 3410b, 397b; ibid., Cauca, Cleef 679). Variation in number and morphology of the oil bodies apparently is characteristic for Lophocoleaceae, since it has been found not only in this and the other species of Lophocolea reported here but also in European material of Lophocolea and Chiloscyphus (unpubl. obs.). |
| Tipo: Article / Letter to the editor |
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| Ano: 1977 |
URL: http://www.repository.naturalis.nl/record/534852 |
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| Registros recuperados: 30 | |
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