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| Registros recuperados: 30 | |
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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.. |
| 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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| 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.. |
| 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.; 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.; Hekking, W.H.A.. |
| □ The main purpose of this catalogue is to provide a complete listing of the species of liverworts hitherto known from Colombia and to summarize our present knowledge of species distribution within the country. It was prepared parallel to a catalogue of the mosses (Musci), which is being published elsewhere (Florschütz & Waard in press). The data were extracted from the available literature and from unpublished determinations of collections from U and COL, made in Colombia by A.M. Cleef (Utrecht), T. van der Hammen (Amsterdam), H. Bischler (Paris) and others. While the first author is responsible for the taxonomy and nomenclature of the taxa, the second author is responsible for the data on species distribution and collecting. □ The literature on... |
| Tipo: Article / Letter to the editor |
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| Ano: 1979 |
URL: http://www.repository.naturalis.nl/record/534863 |
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| Griffin, D.; Gradstein, S.R.; Aguirre C., J.. |
| Dendrocryphaea latifolia sp.nov. from the Páramo de Chisacá, Colombia is described and illustrated. It is allied to D. cuspidata from austral South America but differs from that species in the broader leaves, globose capsules and the basally smooth exostome teeth. A key to the four species of Dendrocryphaea and a conspectus of the genus are provided. D. ramosissima is reduced to synonymy under D. lechleri. Dendrocryphaea is a rheophytic genus with antipodal distribution. Its discovery in the high Andes of Colombia extends to 34 the number of genera of bryophytes with similar antipodal affinities known from the páramos of the northern sector of the Andean cordillera, The nature and origin of these distribution patterns is discussed. In the case of... |
| Tipo: Article / Letter to the editor |
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| Ano: 1982 |
URL: http://www.repository.naturalis.nl/record/534825 |
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| Gradstein, S.R.; Melick, H. van. |
| First record of Bryum gemmiparum de Not. from The Netherlands. The taxonomy and distribution of the species are discussed. Bryum gemmiparum was collected in a clay-pit along the river Maas in the north of the province of Limburg. This locality seems to be the northernmost one known of the species. Bryum gemmiparum was found growing on steep, rather humid, loamy soils in a luxuriant cover of bryophytes characterized by Anisothecium varium, Riccardia sinuata, Riccardia pinguis, Bryum bicolor, Didymodon tophaceus, and Mniobryum wahlenbergii. A floristical and ecological investigation of this highly interesting bryophyte vegetation in The Netherlands is needed. |
| Tipo: Article / Letter to the editor |
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| Ano: 1972 |
URL: http://www.repository.naturalis.nl/record/535128 |
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| Gradstein, S.R.. |
| The Lejeuneaceae are the largest family of the Hepaticae with over 1500 species in about 90 currently accepted genera (Gradstein, 1980). Much has already been written on the nomenclatural and taxonomic problems associated with the generic names in this family. A brief review of the problems is given, introductory to the proposals presented here. Current generic concepts in Lejeuneaceae are essentially based on Richard Spruce’s treatment of the group in his “Hepaticae of the Amazon and of the Andes of Peru and Ecuador” (Spruce, 1884). Spruce recognized, besides the monotypic Myriocolea Spruce, one single genus, Lejeunea, for several hundreds of species of Lejeuneaceae known at that time. This muchembracing genus was subdivided by Spruce into 37 subgenera.... |
| Tipo: Article / Letter to the editor |
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| Ano: 1982 |
URL: http://www.repository.naturalis.nl/record/534923 |
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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.. |
| 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.; 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.; 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 7-12 in upper leaf cells, 10-20 in elongated basal leaf cells; globose to ellipsoid, 3-7(-10)x3-5 μm; colourless, coarsely segmented, consisting of c. 15-30 aggregated droplets (Colombia, Boyacá, páramos NW of Belén, Cabeceras Q. El Toral, 3765 m, Cleef 2292e; Ecuador, páramos de El Angel, 17 km. S. of Tulcán, 3350 m, Gradstein, Lanier & Weber s.n.). The presence of segmented oil bodies in Colura patagonica is remarkable because previous studies of living Colura (from Japan) reported homogeneous oil bodies (cf. Schuster & Hattori 1964; Inoue 1974). |
| Tipo: Article / Letter to the editor |
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| Ano: 1977 |
URL: http://www.repository.naturalis.nl/record/535047 |
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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.. |
| On 27 May 1976 Peter Arnold Florschütz, bryologist, died at the age of only 53 at De Bilt, Netherlands. Only six weeks prior he had been hospitalized as a result of kidney cancer. His untimely death came as totally unexpected and shocking news to his friends and colleagues all over the world, many of whom had seen him in excellent health the year before at the Botanical Congress in Leningrad. He was a lector of botany and curator of the cryptogamic herbarium at the Institute for Systematic Botany and acting director of the Botanical Gardens of the University of Utrecht, the same institution where he had studied biology from 1941 to 1949. In his professional capacity he had held positions at the Institute for Systematic Botany from 1946 until 1949 as... |
| Tipo: Article / Letter to the editor |
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| Ano: 1977 |
URL: http://www.repository.naturalis.nl/record/534931 |
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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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| Registros recuperados: 30 | |
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