1,129 research outputs found
Dianthus borbonicus (Caryophyllaceae), a new species from Sicily
Dianthus borbonicus a new species occurring in North-Western Sicily is described and illustrated. It is a rare chasmophyte
belonging to the D. sylvestris group, which is exclusive of a rupestrian stand near Rocca Busambra (Ficuzza). Its macro- and
micromorphological features (seed testa sculptures, and leaf anatomy), ecology, conservation status and a comparison with
the related species are provided too
Multivariate karyomorphometric analysis and taxonomic implications in Allium sect. Cupanioscordum (Amaryllidaceae)
Significant karyological variation occurs amongst different taxa/populations in the A. cupani group. The ancestral diploid chromosome complement is 2n = 16 (x = 8), but populations of A. cupani s.l. also exhibit dysploidy (2n = 14), polyploidy (2n = 4x = 32, 2n = 4x = 30). These different chromosome assets are associated to specific diagnostic morphological characters and well-defined eco-geographical patterns, which cluster different taxa and populations in 5 series (Brullo&al. 1995, 2008). In order to test the impact of inter-and intra-specific variation in chromosome structure on the systematic treatment of the A. cupani group and its contribution to allow comparing and understanding affinities and relationships among taxa, multivariate statistics was applied to 34 karyomorphometric parameters from 34 samples belonging to 22 taxa which represent the main variability with respect to morphological, cytological and ecological patterns within A. cupani s. l
Taxonomic and phylogenetic relations of Allium chamaespathum Boiss., a remarkable species of Balkan Flora
Allium chamaespathum Boiss., the only autumn-flowering species of Sect. Allium, was studied based on morphology, karyology, seed coat microsculpturing and DNA sequences from several populations
Variabilità morfologica e ultrastrutturale dei semi nel gruppo di Allium cupanii (Alliaceae, Sez. Cupanioscordum)
Indagine fitosociologica sulle praterie a Brachypodium Retusum (Pers.) beauv. della Sardegna
The grasslands characterized by the dominance of Brachypodium retusum occurring in Sardinia are examined. These communities, belonging to the Thero-Brachypodion ramosi alliance (Lygeo-Stipetea class), are quite widespread in the Island, where they usually grow on carbonate substrata from the sea level up to 1300 m of altitude. On the basis of several phytosociological relevés, it has been possible to recognize six associations well-differentiated from the floristic, ecological and syndynamic point of view. The autonomy of these associations is also supported by a numerical multivariate analysis based on quantitative data (dendrogram and P.C.A.). The associations surveyed are the following: Dorycnio suffruticosi-Stipetum offneri ass. nova, localized on summit plateaux at an altitude of 700-1200 m (CE
Sardinia), Stipo bromoidis-Astragaletum verrucosi ass. nova, very rare and circumscribed to the coastal
hills (W Sardinia), Triseto splendentis-Brachypodietum retusi ass. nova, colonizing more or less stabilized
screes at 200-900 m of altitude (NE Sardinia), Asphodelo africani-Brachypodietum ramosi Biondi & Mossa 1992 corr., thermo-xerophilous community linked to coastal stands (S Sardinia), Ranunculo graminei-Brachypodietum retusi ass. nova, orophilous community growing on jointed rocky places at an altitude of 1100-1300 m (CE Sardinia), Melico ciliatae-Brachypodietum retusi ass. nova, found on the
coastal screes of Figarolo islet (NE Sardinia). Besides, a floristic comparison among the hitherto known associations belonging to this alliance is given
Variabilit\ue0 morfologica e ultrastrutturale delle cipsele delle specie siciliane di Helichrysum (Asteraceae)
Si riportano i risultati di uno studio sui caratteri morfologici e ultrastrutturali delle cipsele dei taxa siciliani di Helichrysum e sulla variabilit\ue0 esistente con lo scopo di valutarne l'uso a fini tassonomici. Campioni di diaspore, relativi a 23 accessioni di 12 diversi taxa, sono stati sottoposti a esame macro-micromorfologico e ultrastrutturale al SEM. I dati sono stati elaborati statisticamente mediante ANOVA e varie analisi multivariate (AFD, ACP, CAG)
Biosystematic researches on Allium cupani group (Amaryllidaceae) in the Mediterranean area
Allium cupani Raf. is a species complex of the subgenus Allium L., which is taxonomically quite critical mainly for its marked karyological and morphological variability. In the present study, karyo-taxonomic characterization of some peculiar populations of this group from Italian, N African, Balcan and Aegean territories has been performed, using both living plants collected in the field and herbarium material. As a result, ten new species have been recognized and described within the A. cupani complex. They are A. panormitanum from N Sicily, A. samniticum from C Italy, A. mauritanicum from N Morocco and NW Algeria, A. balcanicum from mountains of Balkan Peninsula, A. tzanoudakisanum from Aegean area, A. cephalonicum from Cephalonia island, A. meikleanum from Cyprus, A. pelagicum from Lampedusa island, A. maghrebinum from Tunisia and NE Algeria, and A. tingitanum from N Morocco and NW Algeria. A comprehensive description and detailed illustration, together with significant notes on karyology, phenology, ecology, geographic distribution, and taxonomic relationships are provided for each species
The Querco-Fagetea class in Sicily: an example of boreal temperate vegetation in the central Mediterranean area
Note tassonomiche e biosistematiche su Anthemis aeolica (Asteraceae).
Sono riportati i risultati relativi alla caratterizzazione morfologica, distribuzione attuale , ecologia e correlazioni sistematiche della specie endemica Anthemis aeolic
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