440 research outputs found
Taxonomic results of the Bryotrop expedition to Zaire and Rwanda : 24., Leskeaceae, Brachytheciaceae, Stereophyllaceae, Plagiotheciaceae, Entodontaceae, Sematophyllaceae p.pte, Hypnaceae (except Hypnum)
This very distinctive and easily recognized moss has terete foliation when dry, and has leaves spreading when moist. The leaves are ovate, abruptly broad-acuminate, about 1.5-2 mm long, and strongly plicate. The single costa extends to the base of the acumen, and the laminal cells are 1-2(-3):1 and low unipapillose
Biogeography of the Greater Antillean mosses
The distinctions between dispersal and vicariance are discussed and shown how they relate to geological history. Postulated theories on the tectonic origins and history of the Greater Antilles are reviewed, as well as possible climatic events that would affect biogeography. Numerous zoological examples are presented to argue both dispersalist and vicariance viewpoints. It is proposed that the modern moss flora of the Greater Antilles is best explained primarily by dispersal events. Post-vicariant events, such as Pleistocene climate changes, would have extirpated the vast majority of mosses from the islands and even among those taxa that survived, disperal by the same taxa would have obscured their origins. It is assumed that many of the North American elements in the high elevations of Hispaniola are a result of invasions during the Pleistocene. The Andean elements are considered relatively recent dispersally derived taxa that have successfully colonized the Antilles because of ecologically compatible habitats
On the variation of leaf border in Rhizomnium (Cinclidiaceae)
In the genus Rhizomnium T. Kop. most taxa have a strong leaf border several cells broad and bi- to tristratose. Rhizomnium striatulum (Mitt.) T. Kop. belongs to that group. In Northeast China one population of R. striatulum was found with a very weak leaf border, and also the costa of these plants is weaker than is characteristic for the species. The deviating population is figured and its significance discussed. The distribution of R. striatulum is mapped
Bryophytes of Uganda : 5., Bryocrumia L.E.Anderson (Hypnaceae) ; a monotypic moss genus new to Africa
A number of collections from Africa identified as Phyllodon scutellifolius or Glossadelphus serpyllifolius belong to Bryocrumia vivicolor, previously known only from America and Asia. Phyllodon scutellifolius is known only from one (possibly two) collections from Madagascar, and Glossadelphus serpyllifolius is a synonym of Bryocrumia vivicolor
Plagiothecium lucidum (Hook. f. & Wils.) Paris in tropical Africa
Plagiothecium lucidum (Hook. f. & Wils.) Paris is confirmed as a new addition to the bryoflora of tropical Africa on the basis of two collections from the Bale Mountains in Ethiopia. The type material of Isopterygium integrifolium Bartr. from Costa Rica in Central America is evaluated and this species is considered to be conspecific with P. lucidum. As a result of this taxonomic conclusion the range of this species is extended to Costa Rica and this is the first recognition of this species in the Central American isthmus. A world distribution map for this species is presented and some details of African plants and the type of I. integrifolium are illustrated
Bryophytes from the Republic of Equatorial Guinea (West-Central Africa) : 2., bryophytes collected by Emilio Guinea (1907-1985) in the Island of Bioco in 1947
Some unidentified samples of bryophytes collected by Emilio Guinea in Bioco (Equatorial Guinea) in 1947 have been studied. Twenty-seven taxa are the result of this study, nine of them being new for Equatorial Guinea and two new for the island of Bioco.Se han estudiado varias muestras de briĂłfitos sin identificar recogidas por Emilio Guinea en Bioco (Guinea Ecuatorial) en 1947. Veintisiete taxones son el resultado de este estudio, siendo nueve de ellos novedad para Guinea Ecuatorial y dos mĂĄs, nuevos para la isla de Bioco
Campylopus steerei (Dicranaceae), a new paraleucobryoid species from South American PĂĄramos
The Campylopus paraleucobryoid complex, restricted to Andean South
America, is discussed and a new species, C. steerei, is described. These plants differ
from other members of the complex in having all dorsal (abaxial) surface cells
with very thick, orange outer walls. Additionally, Campylopus erratus nom. nov. is
provided to correct an earlier nomenclatural error. A key is included to separate
the five species in the comple
Re-assessment of type material of Plagiothecium novae-seelandiae Broth. and descriptions of four new Plagiothecium taxa (Bryophyta, Plagiotheciaceae) from Australasia
A re-examination of the original collection of Plagiothecium novae-seelandiae described by Brotherus in 1916 indicated that this material is not homogeneous. Re-examination of the diagnosis of this species and morphological analysis supports that two separate taxa should be distinguished â Plagiothecium novae-seelandiae var. novae-seelandiae and P. novae-seelandiae var. brotheri var. nov. Also, comparisons with the original collection of Hypnum lamprostachys (= P. lamprostachys) showed differences, which supported their treatment as separate taxa. Revision of the genus Plagiothecium from Australasia (CANB, CHR, HO, MEL, WELT) and types of other species described from this part of the world (P. funale and P. lucidum) supported by the study of their diagnoses, qualitative and quantitative characteristics as well as mathematical analyses (PCA, HCA) allowed the division of the examined material into six separate groups â six separate taxa. Thereby, three distinct taxa are proposed â P. cordatum sp. nov., P. semimortuum sp. nov., and P. semimortuum var. macquariense var. nov. All taxa mentioned above are described in detail, their current known distribution and ecological preferences are also included. In addition, images illustrating their most important taxonomic features, as well as an original key to distinguish individual taxa are presented
Interactions of Bioactive Trace Metals in Shipboard Southern Ocean Incubation Experiments
In the Southern Ocean, it is wellâknown that iron (Fe) limits phytoplankton growth. Yet, other trace metals can also affect phytoplankton physiology. This study investigated feedbacks between phytoplankton growth and dissolved Fe, manganese (Mn), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), and cadmium (Cd) concentrations in Southern Ocean shipboard incubations. Three experiments were conducted in SeptemberâOctober 2016 near the West Antarctic Peninsula: Incubations 1 and 3 offshore in the Antarctic Circumpolar Current, and Incubation 2 inshore in Bransfield Strait. Additions of Fe and/or vitamin B12 to inshore and offshore waters were employed and allowed assessment of metal (M) uptake relative to soluble reactive phosphorus (P) across a wide range of initial conditions. Offshore, treatments of \u3e1 nmolâLâ1 added Fe were Feâreplete, whereas inshore waters were already Feâreplete. Results suggest Mn was a secondary limiting nutrient inshore and offshore. No Feâvitamin B12 colimitation was observed. Overall, M:P uptake in the incubations was closely related to initial dissolved M:P for Fe, Mn, Co, Ni, and Cd, and for Cu inshore. Final concentrations of Fe and Zn were similar across light treatments of the experiments despite very different phytoplankton responses, and we observed evidence for Co/Cd/Zn substitution and for recycling of biogenic metals as inventories plateaued. In dark bottles, the absence of Mn oxidation may have allowed more efficient recycling of Fe and other trace metals. Our results provide insight into factors governing trace metal uptake, with implications for phytoplankton community composition locally and preformed micronutrient bioavailability in Southern Ocean water masses
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