Giovanna Abbate

Lemna valdiviana Phil. (Araceae) as a potential invasive species in Italy and Europe: Taxonomic study and first observations on its ecology and distribution

Abstract Lemna valdiviana Phil. and L. minuta Kunth are native species of the Americas. At present L. minuta colonizes in Europa and Asia, where it is often considered an invasive alien species. Recent floristic surveys in the Agro Pontino area (Lazio region, central Italy) allowed to find a population referring to L. valdiviana, supported by the recent gathering in Sardegna region. With the aim to identify correctly the two species, we carried out a morphometric study based on measurements of both qualitative and quantitative characters, made on herbarium and living specimens collected from America and Europe. The univariate and multivariate analyses clearly support the attribution of the population from Lazio to L. valdiviana. This gathering is the first record of this species for the Italian peninsula. Moreover, the checking of Herbaria allowed us to find the older specimen of L. minuta collected in Europe (around 1877). At present L. valdiviana is to be considered as a casual alien species in Agro Pontino, but the rapid colonization of the aquatic environments by Lemna species by means of vegetative reproduction allows us to recognize it as a potential invasive species.

Typification of Trifolium latinum Sebast. (Fabaceae) and Comparison with Similar Species

Based on a plate from the protologue by Antonio Sebastiani and a specimen in RO, a lectotype and an epitype, respectively, for Trifolium latinum Sebast. are designated here.

Woody flora as a predictor of vascular plant richness: An insight in Italy

A key problem in quantifying biodiversity is whether it is possible to infer the overall diversity using suitable data subsets. The aim of this article, based on the updated data on the native woody flora of Italy, is to evaluate the reliability of such data as a predictor of vascular plant richness at a medium scale represented by the 20 administrative regions. Woody taxa were divided in trees, shrubs and lianas. We used stepwise multiple regression and principal component analysis to analyse the correlation between environmental heterogeneity, vascular plant units (species and subspecies) richness and woody units’ richness. Woody flora of Italy consists of 61 families, 133 genera, 469 species and 509 units. Shrubs constitute 74% of the woody flora, trees and lianas of 23% and 3%, respectively. Both stepwise multiple regression analysis and two principal component analyses strongly suggest that woody units, and trees in particular, are correlated with total vascular plant richness, at all hierarchical taxonomical levels. The environmental heterogeneity has been demonstrated to be much more important than the area for the biodiversity of Italian regions. Woody flora, as a surrogate of total flora, is extremely useful for rapid assessments of overall vascular plant diversity that may be exploited for monitoring purposes.

Morphological study of three taxa of the genus Rubus L. sect. Rubus (Rosaceae) in Western Central Italy

ABSTRACT The three most frequent taxa of Rubus subgen. Rubus sect. Rubus in Western Central Italy are here examined from a morphological point of view. The study is based mostly on new collections. The morphological variability of each taxon is analyzed at the regional scale, and a complete description for the three entities is provided.

Detecting Phytogeographic Units Based on Native Woody Flora: A Case Study in Central Peninsular Italy

We present a statistically derived phytogeographic regionalization based on the spatial distribution of native woody flora, investigating environmental correlates and assessing congruence between the spatial patterns of species, genera, and families. A sector of central peninsular Italy (Lazio and Abruzzo regions) was selected as a case study. A rich georeferenced floristic database was compiled, including information from different sources. A total of 43,968 occurrence data, 290 10 × 10 km cells, 224 species, 103 genera, and 80 families was used; Ward’s clustering was performed to identify phytogeographic units. Three well-defined and relatively spatially coherent units were identified at the species, genus, and family levels: a Mediterranean unit, a Transition unit, and a Eurosiberian one. Congruence between taxonomic levels was well supported. Further divisions in subunits were detected using species data. The main environmental descriptors of the clusters were distance from the sea, elevation, temperature, and lithology.

Salt glands of Armeria canescens (Host) Boiss.: Morphological and functional aspects

Abstract The morphology and functionality of salt glands in four Italian Armeria canescens populations were investigated. Microscopic analysis showed that salt glands consist of 16 cells arranged in four quadrants, including four subsidiary cells and 12 gland cells. The main secreted elements are K, Ca and Cl, although qualitative and quantitative differences were observed between gland and subsidiary cells. Soil characteristics like texture, pH and C/N ratio were shown to vary between population sites. The highest number of glands per leaf area was found in plants from Ca-rich sites. Although A. canescens is not a halophilous species, its salt glands were revealed to be active, suggesting that they could represent an ancestral character.

A morphometric study of Armeria canescens aggr. (Plumbaginaceae) in the Italian Peninsula

Armeria Willd. is a genus of diploid, self-incompatible plants with weak internal reproductive barriers, in which hybridisation and introgression play a fundamental role and are partly responsible for patterns of variation. One of the most critical groups in Italy comprises Armeria canescens (Host) Ebel and Armeriamajellensis Boiss., species living in grasslands and pastures of central and southern Apennines. The taxonomic status of A. majellensis is not clear: for some authors it must be considered as a species endemic to Italy, but according to others it must be included in A. canescens because of their poor morphological separation. With the aim of clarifying the real status of A. majellensis and its relationship with A. canescens, we performed a morphometric study using materials coming from field collections throughout their Italian distribution area, herbarium specimens and samples coming from the loci classici of the species. The morphometric multivariate analyses showed that there are no significant differences in morphology among the Italian sampled populations referable to A. canescens/A. majellensis and so they should be referred to the same biological entity. The priority name for the A. canescens/A. majellensis complex, at the specific level, is A. canescens.

Lectotypification of Statice canescens Host and Armeria majellensis Boiss. (Plumbaginaceae)

We designate lectotypes for Statice canescens Host [= Armeria canescens (Host) Ebel] and A. majellensis Boiss. (Plumbaginaceae), selected from the original material stored at the Herbarium of Naturhistorische Museum in Wien (W) and at the Herbarium of the Conservatoire et Jardin Botaniques de la Ville de Genève (G), respectively.

Contribution to the vascular flora of the Castelli Romani Regional Park (Rome, Central Italy) with recent observations and early herbarium surveys.

Summary We report the results of a floristic survey carried out in the Castelli Romani Regional Park (Rome, Central Italy) during the years 2003–2008, supplemented with data derived from recent literature. The Park includes part of Colli Albani, four SCIs and a SPA. The purpose of this study was to assess the actual floristic value of an area close to the city of Rome, yet still at medium floristic knowledge. The area has peculiar features in terms of lithomorphology (volcanic rocks, volcanic lakes), soils (andisoils, brown soils), and phytoclimate (Mediterranean Transitional Region, Temperate Region). The floristic list is composed of 796 units belonging to 783 species, 420 genera, and 102 families. One species, Sechium edule (Jacq.) Sw., is new to Lazio Region. The woody flora reaches 12.06%, while, as for the herbaceous flora, Hemicryptophytes slightly prevail over Therophytes. As regards chorotypes, together with a considerable number of Mediterranean s. l. and of European species, there are many species with wide distribution area, testifying a longlasting and deep urban impact which started many decades ago. The flora of the Park is similar enough, both in structural and geographical terms, to the flora of the volcanic district of Vico (northern Lazio Region); a detailed comparison concerning aquatic and hygrophilous flora between the two areas pointed out similar sets of rhizophyte species, whereas in the lakes of Albano and Nemi helophyte belt and wet meadows are lacking. Quite few species that are rare or extremely rare to Lazio Region or included in the Regional Red Lists of the Italian Plants were recorded. Nevertheless, some of them have a high biogeographical value (e.g., Vicia sativa subsp. incisa, Adenocarpus samniticus) or are typical of rare environments (Potamogeton sp. pl.). A test study limited to Lycopodiophyta, Ferns and allies, and Orchidaceae was carried out on ancient herbarium specimens kept in the Herbarium RO, showing that 21 units are today no longer recorded.

Control of invasive species for the conservation of biodiversity in Mediterranean islands. The LIFE PonDerat project in the Pontine Archipelago, Italy

Abstract We present the EU LIFE PonDerat project, which is aimed at restoring the natural ecosystems of the Pontine Archipelago, a group of islands located off the western coast of Italy. The spread of invasive species is a major environmental threat on these islands, which are rich in rare habitats and endemic species and are important sites for the conservation of Mediterranean biodiversity. The project focuses on the conservation of species and habitats that are protected by EU laws but are currently threatened by introduced plants and animals. The main targets of the control measures are black rats, feral goats, mouflons and invasive plants of the genus Carpobrotus. Conservation measures focus on the shearwaters Puffinus yelkouan and Calonectris diomedea, which are endemic to the Mediterranean and are listed in Annex I of the European Bird Directive. Conservation measures also focus on island habitats of great biogeographical value, which are listed in Annex I of the European Habitats Directive and are seriously threatened by introduced herbivores and by invasive plants. The main outcome expected from this project is that the restoration of ecosystem functions will enhance the breeding success and population size of shearwaters and lead to the recovery of target habitats.