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Abstrakt

Schistidium urnulaceum (C. Muell.) B. G. Bell, a species hitherto known from the sub-Antarctic island of South Georgia, is reported for the first time from King George Island, South Shetland Islands, in the Antarctic botanical zone. A description of the species together with illustrations, notes on habitat and a distribution map are provided. Taxonomic notes to assist in the identification of S. urnulaceum are also given.
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Abstrakt

On the basis of comparable habit, leaf morphology and leaf cell pattern, leaf and stem sectional anatomy, Dichelyma antarcticum C. Muell. is reduced to synonymy with Blindia magellanica C. Muell.
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Abstrakt

On the basis of the distinctly biplicate and carinate leaves in the distal portion Grimmia lawiana J.H. Willis, the only continental Antarctic endemic moss species, is transferred to the genus Coscinodon Spreng. and the new combination C. lawianus (J.H. Willis) Ochyra is proposed. The species is described and illustrated, its affinities are discussed and its geographical distribution in the Antarctic is mapped. Grimmia reflexidens Müll. Hal., a southern South American endemic species from Chile , is briefly assessed and this species is also shifted to Coscinodon as C. reflexidens (Müll. Hal.) Ochyra, comb. nov. A key to all species of the genus Coscinodon is presented. Guembelia longirostris (Hook.) Ochyra et Żarnowiec is reported for the first time from the Antarctic on the basis of a specimen collected from the Nordenskjöld Coast on the eastern coast of the Antarctic Peninsula.
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Abstrakt

Schistidium cupulare (Müll. Hal.) Ochyra, an obscure and poorly known species originally described from Îles Kerguelen as Grimmia cupularis Müll. Hal. and subsequently reported from a single station in the Antarctic, is re-assessed taxonomically. It is considered to be a distinct species of sect. Conferta, closely related to S. amblyophyllum (Müll. Hal.) Ochyra et Hertel, from which it differs in its distal- and mid-leaf areolation of short, isodiametric, quadrate to shortly rectangular cells; stouter costa, 50–75 μm wide in the distal and median part, semi-terete to subrectangular in cross-section and prominently convex on the dorsal surface, (2–)3-stratose above, 3(–4)-stratose below; leaf margins regularly 2–3-stratose in 1–3 rows of cells forming fleshy, bulging limbidia; presence of a distinct central strand; and finely roughened to nearly smooth peristome teeth. S. celatum (Cardot) B.G. Bell from South Georgia and Tierra del Fuego is considered to be conspecific with S. cupulare. Some details of the type specimens of both species are illustrated. The geographical range of S. cupulare is evaluated and it is considered to be an amphiatlantic subantarctic species. A new record of the species from Livingston Island in the Antarctic is provided and a key to species of Schistidium in Antarctica is given.
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Abstrakt

This paper reports on eleven species of hepatics collected on King George Island, South Shetland Islands (6Г50'—62°15'S latitude and 57°30'—59 00'W longitude). A short account of the vegetation of this Antarctic island is provided and the role of liverworts in particular plant communities is discussed. Two species, Hygrolembidium ventrosum (Mitt.) Grolle and Scapania abcordata (Berggr.) S. Arnell are reported for the first time from the Antarctic botanical zone; the latter is recorded for the first time in the Southern Hemisphere and, additionally, this is the first record of the genus Scapania from Antarctica. A detailed description of the habitat of each taxon is given and distribution maps for the eleven species are provided. A key to the eleven species from King George Island is given, and a detailed taxonomic discussion is included for Cephaloziella varians (Gott.) Steph and Lophozia excisa (Dicks.) Dumort. The former is considered to be synonymous with the widespread Arctic species C. arctica Bryhn & Douin ex K. Müll.
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Abstrakt

A short review of the history of the hepaticological exploration of Antarctica is given in the present paper. An annotated check list of all taxa of hepatics reported from within the Antarctic botanical zone, based on literature data and unpublished records, is included. Altogether 22 species of liverworts, excluding two taxa known only at generic level, representing 18 genera and 13 families, are known to occur in the Antarctic. All species of hepatics, except for Cephaloziella varians which is also known from Greater Antarctica, occur exclusively in the maritime Antarctic region. In the livewort flora of Antarctica, the southern temperate and subantarctic elements are predominant (72.7%) and the bipolar element is remarkably scarce, albeit the bipolar taxa belong to the most widespread and frequent of the impoverished Antarctic hepatic flora. Distribution patterns of all known Antarctic liverworts are briefly discussed and several floristic elements and subelements are recognized.
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Abstrakt

Grimmia andreaeopsis C. Muell., a species described from sterile material from the Chukotka Peninsula, is redescribed and illustrated The species is actually a member of the genus Schistidium. It can be distinguished from its closest relatives, viz. species of S. strictum complex, by the possession of a unique combination of characters: (1) inky black coloration of gametophytes; (2) strongly and asymmetrically keeled, rapidly wide-spreading to squarrose when moist, leaves; (3) cells entirely smooth, very incrassate and strongly nodulose nearly to the base of the lamina: (4) a costa totally smooth or only occasionally slightly roughened on the back below the apex, but never scabrous with conical papillae; (5) leaf margins always entire; (6) peristome teeth bluntly acuminate. Unlike most rupestral species of Schistidium it grows in wet arctic fens. S. holmenianum Steere & Brassard, a species known to be widely distributed in the Nearctic, and Racomitrium depressum Lesq. var. nigricans Kindb., a variety described from Labrador and Hudson Bay. are synonymous with S. andreaeopsis (C. Muell.) Laz. A comparison of S andreaeopsis with the Andean-Subantarctic S. anqustifolium (Mitt.) Herz is made and these species are considered to be closely related, but not conspecific, bipolar counterparts. Also, a comparison with the South Georgian S. urnulaceum (C. Muell.) Bell and the Holarctic species of S. strictum complex, which are characterized by having similar leaf cell patterns, is made. S. andreaeopsis has a circumpolar distribution, mainly within the High Arctic. In addition to the Nearctic, the species is known to occur in Svalbard, North Land, Taymyr Peninsula, Yakutia, Wrangel Island, and on the Chukotka Peninsula.
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