Lorenzo Gianguzzi

Phytosociological survey vegetation map of Sicily (Mediterranean region)

ABSTRACT We present the results of a study aimed at developing a vegetation map of Sicily (Italy) including the smaller circum-Sicilian islands, for an area of approximately 25,703 km2. The work is a synthesis of studies carried out in accordance with the survey methodology of phytosociology in the last 40 years over the whole study area. The vegetation map of Sicily was compiled in a Geographical Information Systems (GIS) environment, in order to produce a cartographic representation at a scale of 1:10,000 (reduced to a scale of 1:250,000). The physiognomic-structural characteristics of the plant landscape of Sicily are analyzed, providing a general and, at the same time, detailed overview of the phytocoenotic aspects represented on the territory, as well as of the relative bibliographic references. At the reference scale, 36 types are represented, 16 of which are related to zonal vegetation (Mediterranean maquis, Quercus ilex woods, Quercus suber woods, Castanea sativa woods, Quercus pubescens deciduous woods, mesophilous deciduous woods, Fagus sylvatica woods, Betula aetnensis woods, woods dominated by woody gymnosperms, forest edge shrubs, orophilous pulvinate shrubs, shrublands and garrigues, Ampelodesmos mauritanicus grasslands, mesophilous and sub-hygrophilous grasslands and pastures), 11 are related to azonal vegetation (riparian, psammophilous herbaceous, chasmo-halophitic, etc.) and 9 are related to anthropogenic vegetation (arable lands and extensive herbaceous crops, vineyards, olive groves and dry cultivation mosaics, hazelnut groves, irrigated citrus groves and orchards, greenhouses, built-up areas).

Bio-ecological, phytosociological and conservation aspects of relictual and disjointed populations of Simethis mattiazzi (Vandelli) Sacc. (Xanthorrhoeaceae) in the Channel of Sicily

Abstract Two populations of Simethis mattiazzi (Xanthorrhoeaceae) were recently discovered in the Channel of Sicily – (1) Punta Bassana (Marettimo Island) and (2) Mount S. Giuliano (western Sicily) – at a considerable distance from the nearest stations hitherto known, located in southern Sardinia, the Pontine Islands Archipelago and Tunisia. The taxonomical and distributive aspects of this species are analysed to highlight the relictual and biogeographical significance of the disjointed and fragmentary nuclei distributed in several small islands of the Channel of Sicily, the Italian Peninsula and North Africa. Some morphological, biological, ecological and phytosociological aspects of the two new populations are analysed to assess risk factors. These relictual populations are included in a residual garrigue ascribed to the association Erico–Micromerietum fruticulosae, endemic to western Sicily and characterized by a significant frequency of endemic or rare species. The coenose is tied to the calcareous dolomite rocky ridges located near the coast and exposed to humid currents from the sea; this ecological combination gives to the habitat a character of oceanic environmental conditions, somewhat similar to the Atlantic stations where the main range of the species gravitates. The survey has shown the populations to be formed of a small number of individuals at both stations, which has further highlighted the biological precariousness of these populations, located at the extreme south-eastern limit of the range of the species. The threats of anthropogenic nature, such as reforestation with non-native conifers, but mostly by fires, the frequency of which tends to alter the integrity of the sites, increase this vulnerability. The IUCN “risk status” for the regional territory of Sicily of S. mattiazzi is to be ascribed to the “Critically endangered” category, in accordance with the B1ab (ii) and B2ab (ii) criteria of the IUCN. The same “risk status” is likely to be extended to the other isolated stations of the western Mediterranean.

Flower and fruit structure of the endangered species Petagnaea gussonei (Sprengel) Rauschert (Saniculoideae, Apiaceae) and implications for its reproductive biology

Petagnaea gussonei (Apiaceae) is an endangered species endemic to the Nebrodi mountains (north-eastern Sicily). Although an increasing number of studies have been performed on this species, its reproductive biology remains poorly understood. The aim of this study was to investigate in detail the structure of the flower and the fruit of Petagnaea, and the possible implications for its breeding system and seed dispersal mechanism. Results from fieldwork, light microscopy and scanning electron microscopy suggest (1) the presence of protandrous hermaphrodite flowers; (2) geitonogamy, autogamy, and allogamy as breeding system mechanisms of P. gussonei, even if asexual reproduction is preferred by the plant; and (3) epizoochory and hydrochory as possible modalities of fruit dispersal.

Distribution, ecology, vegetation and conservation survey on the relictual population of Carex panormitana Guss. (Cyperaceae) in Sicily (Italy)

We report the results of research on the Carex panormitana Guss. (Cyperaceae) population in Sicily, carried out within its locus classicus at the Oreto River (Palermo). The survey led to a morphological, biological and autoecological characterization, to the definition of the current distribution in the site, to an estimate of the number of individuals and to an analysis of its conservation status. The risk status was also assessed and the species was ascribed to the category Critically Endangered (CR), in accordance with the CR B1ab (ii, iii, v) and EN C1 IUCN criteria. Moreover, the phytosociological survey carried out on the meso-hygrophilous vegetation in which the species is dominant allowed description of the association Caricetum pendulo-panormitanae ass. nova, in turn framed into the alliance Magnocaricion elatae (ord. Magnocaricetalia, cl. Phragmito-Magnocaricetea).

Distribution, ecology and conservation survey on Trifolium michelianum Savi (Fabaceae) in Sicily (Italy)

We report the identification of four residual stations for Trifolium michelianum Savi (Fabaceae) in Sicily, whereas the species was documented to be extinct at the Gorgo Cerro station (western Sicily), the only locality previously reported in the literature. In addition to an update on the distribution of the species, a survey on the new Sicilian populations led to their biological, ecological and phytosociological characterization, as well as to an assessment of the risk factors. The species, here relegated to the limit of its distribution area, occurs in particularly sensitive and vulnerable environments, such as the “Mediterranean temporary ponds”, considered “priority” by the Council Directive 92/43/EEC. Moreover, a new Sicilian association (Trifolio micheliani–Glycerietumspicatae ass. nova), framed in the alliance Glycerio-Sparganion (class Phragmito-Magnocaricetea), is described.

First record of Ribes uva-crispa L. (Grossulariaceae) from the Madonie Mts., a new species of the Sicilian flora

Abstract In this study, a first record of Ribes uva-crispa L. (Grossulariaceae) – a new species of the Sicilian flora – from the Madonie Mts. is reported. The autochthonous and relict new population of Ribes uva-crispa L. (Grossulariaceae) is found on Mount Carbonara (Madonie Mts., North-Central Sicily), which is several hundred kilometers away from the Central Apenninic and the South Mediterranean locations of its distribution range. R. uva-crispa shows a distribution similar to other taxa extending from the Euro-Asiatic area to the mountains of North Africa with disjunct populations on the main Sicilian reliefs (Madonie and Nebrodi Mts.), testifying ancient phytogeographical connections. This noteworthy record adds a new species – as well as a new genus and new family – to the vascular flora of Sicily. Based on the morphological characters, the population found is to be referred to Ribes uva-crispa L. subsp. austro-europaeum (Bornm.) Bech var. glanduligerum (Lindberg) Maire.

Distribution, ecology and conservation survey on the Celtis tournefortii subsp. aetnensis (Celtidaceae: Cannabaceae) populations in Sicily

Results of research on the Celtis tournefortii subsp. aetnensis (Celtidaceae: Cannabaceae) populations in Sicily, based on the monitoring of the various nuclei distributed in the territory, are presented. In particular, two new important unpublished stations located in the southern part of the Sicani Mountains, widespread over an area of approximately 75 hectares, are reported. It is highlighted that the species, besides the lava flows of the western slope of Mount Etna (Catania province), is tied to conoids present in five other disjointed sub-ranges, often with fragmentary and relictual stations: (1) Nebrodi Mountains inland (Cesarò territory, Messina province); (2) Madonie Mountains inland (Gangi territory, Palermo province); (3) northwestern sector, in the Palermo province (Rocca Busambra); (4) southwestern Sicani Mountains (Pizzo Telegrafo, in Contrada S. Biagio and in the Caltabellotta territory, Agrigento province); (5) southeastern Sicani Mountains (S. Stefano di Quisquina at Pizzo Castelluzzo, Agrigento province). In addition to a herbarium exsiccata census, the survey led to a biological and autoecological characterization, to the definition of the current distribution, to an estimate of the number of individuals and to an analysis of its conservation status. The risk status was also assessed and the species was ascribed to the category Endangered (EN), in accordance with the B1ab(iii) and B2ab(iii) IUCN criteria.

Checklist of gypsophilous vascular flora in Italy

Abstract Our understanding of the richness and uniqueness of the flora growing on gypsum substrates in Italy has grown significantly since the 19th century and, even today, new plant species are still being discovered. However, the plants and plant communities, growing on gypsum substrates in Italy, are still a relatively unknown subject. The main aim of this paper was to elaborate a checklist of the Italian gypsophilous flora, to increase knowledge about this peculiar flora and for which conservation efforts need to be addressed. Through a structured group communication process of experts (application of the Delphi technique), a remarkable number of experienced Italian botanists have joined together to select focal plant species linked to gypsum substrates. From the results obtained, 31 plant species behave as absolute or preferent taxa (gypsophytes and gypsoclines) and form the ‘core’ Italian gypsophilous flora. The most abundant life forms were chamaephytes and hemicryptophytes, belonging to Poaceae and Brassicaceae; as for chorotypes, the most represented are Mediterranean and narrow endemics. By improving on previously available information about the flora with a clear preference for gypsum in Italy, this undertaking represents an important contribution to the knowledge of a habitat which is today considered a priority for conservation.

Notes on the distribution, ecology and conservation status of two very rare sedges (Carex, Cyperaceae) rediscovered in Sicily (Italy)

Abstract New data on the geographical distribution and ecology of two rare taxa of Carex collected in the area of the Nebrodi Mountains (Sicily) are provided; the Sicilian populations of both taxa are at the border of their respective ranges, and their regional distribution is still poorly known. The new population of Carex × boenninghausiana reported here confirms the presence of this hybrid in Sicily, but at the same time it represents the only known population currently occurring in Italy; in fact, the other – so far only – known Italian population is considered extinct. The second report concerns Carex grioletii, recently considered doubtful for the Sicilian flora, whose new population here reported is the only confirmed and currently present population in the island; the assessment of extinction risk and conservation status, carried out at regional (Sicilian) level according to the IUCN criteria for the latter taxon, showed that it is Critically Endangered (CR).

Phytosociological analysis of the Genista sp. pl. garrigues of the Cisto-Lavanduletea and Rosmarinetea officinalis classes in the South-Tyrrhenian area (Mediterranean Region)

The study reviews the Genista sp. pl. garrigues ascribable to the classes Cisto-Lavanduletea (acidophilous communities on volcanics and quartzarenites) and Rosmarinetea officinalis (basiphilous communities on calcareous and calcareous-dolomite substrates), in the southern territories of the Italo-Tyrrhenian Province. The floristic-synecological characterization of the identified coenoses led to the description and/or redefinition of various new syntaxa. They are distributed in the two new suballiances Calicotomo villosae–Genistenion tyrrhenae and Genisto aristatae–Calicotomenion infestae of the class Cisto-Lavanduletea (Lavanduletalia stoechadis and Calicotomo villosae–Genistion tyrrhenae), and in the alliance Cisto eriocephali–Ericion multiflorae of the class Rosmarinetea officinalis (Rosmarinetalia officinalis), with two new described associations.