Search results for "Lycopodiophyta"
showing 10 items of 10 documents
The genus Isoëtes L. (Lycophyta, Isoëtaceae): Synthesis of karyological data
2001
Summary A synthesis of relevant karyological data regarding the genus Isoetes is given, with an up-to-date check list of chromosome numbers including 152 records referring to 67 taxa (62 species and 5 infraspecific taxa) and 16 hybrids. Total of different chromosome counts (considering two or more cytotypes for certain taxa, excluding hybrids) is 80. Probable base number is x = 11, even though x = 10 and x = 12 have been proposed for certain species. On the basis of data here summarized, the mean percentage of polyploidy is 61.2%; 31 taxa are diploids (38.8%), 28 are tetraploids (35.0%), 8 are hexaploids (10.0%), with a few species each which are tri-, penta-, octo-, deca- and dodeca-ploids…
Osservazioni sulla flora pteridologica della Sicilia
2011
Biogeographia vol. XXX - 2071 (Pubblicato il 23 dicembre 2011) La Biogeografia della Sici/ia Osservazioni sulla flora pteridologica della Sicilia ANGELO TROIA, VTNCENZO ILARDI, FRANCESCO MARIA RAIMONDO Universita di Palermo - Dz'partz'mem.‘0 a’z' Biologia Ambientale e Biodiversita, via Arckirafi 38, I—90]23 Palermo (Italy); e—mail: ange[0.tr0z'a @[z'ber0.z'2f Key words: flora, pteridophytes, Lycopodiophyta, Monilophyta, ferns, Sicily SUMMARY An updated checll—list of Sicilian pteridophytes is presented: in total, there are 55 taxa, including 49 ferns in the strict sense (“monilophytes”) and 6 lycopodiophytes. Aspleniaceae is the most represented family in terms of speci…
A critical conspectus of ItalianIsoetes(Isoetaceae)
2014
The work on the Isoetaceae account for the Critical Flora of Italy has resulted in a new, synonymic inventory of Italian Isoetes taxa, based on herbarium studies, observation by scanning electron microscopy and critical re-examination of the previously published works. Ten species are listed. The names I. longissima and I. gymnocarpa are restored as correct, to replace I. velata and I. subinermis, respectively. Eighteen lectotypes, one epitype and one neotype are designated. A dichotomous key to Italian taxa is provided.
Isoëtes sabatina (IsoëtaceaeLycopodiophyta), a new aquatic species from central Italy
2013
The new species Isoetes sabatina is described and illustrated. Morphological, anatomical, and ecological characters are given. It differs from the similar I. echinospora by several characters, such as megaspore ornamentation and size, microspore size, velum extension and form, and also for its ecology. A table showing the main differential characters of the new species compared with those of the other European aquatic species is presented. So far, the species is known from a single locality (Bracciano Lake, central Italy), having a peculiar ecology and within the Mediterranean bioclimate.
Contributo alla flora critica d'Italia: i generi della famiglia Lycopodiaceae
2012
Conferma della presenza di Isoëtes velata A. Braun (Isoëtaceae, Lycopodiophyta) nella Sicilia occidentale
2010
Towards a Critical Flora of Italy: Assessing the Lycopodiophyta
2013
Micromorphological approach to the systematics of Mediterranean Isoëtes species (Isoëtaceae, Lycopodiophyta): analysis of the megaspore surface
2012
Megaspore ornamentation is one of the few morphological characters used in the taxonomy of the genus Isoëtes. In the present work, we test the application of this character for distinguishing some Isoëtes species occurring in the Mediterranean: Isoëtes sicula, which according to some authors should be included as a variety in I. histrix, and the recently described I. todaroana, whose affinity with other taxa is currently unknown. Two additional species (I. duriei, I. velata) were also included in the analysis. The megaspores were studied using scanning electron microscopy combined with energy-dispersive X-ray spectroscopy and chemical treatment. In all species, the megaspore surface is cove…
Isoëtes todaroana (Isoëtaceae, Lycopodiophyta), a New Species from Sicily (Italy)
2009
Isoetes todaroana, a new species from western Sicily (Italy), is described. Morpholog- ical, anatomical and ecological characters are given. The main differential characters are the presence of only two leaf air chambers, rather than four as in all other known species of the genus, and the shape of the scales, which have two lateral rounded lobes and one central spine-like lobe, together with its peculiar calcophilic habitat. So far, the species is known from a single locality.