Giuseppina Messina

Diversity of terrestrial isopods in a protected area characterized by salty coastal ponds (Vendicari, Sicily)

The diversity of Oniscidean isopods was studied in Vendicari, a protected area in southeastern Sicily characterized by salty ponds separated from the sea by narrow bands of land. Samples were collected in pitfall traps placed in transects from the coastline to the ponds and from the ponds inland. Twenty-three species were identified, only seven of which were present at all sampling sites. Shannons diversity and Pielous evenness indices revealed higher values in the spring and autumn; activity indices were also calculated for each species for all months of the year. Similarity among sampling sites was evaluated qualitatively with Jaccards index and quantitatively with Sørensens index. The ponds seem to play the same role as the seacoasts regarding species zonation.

The diversity of terrestrial isopods in the natural reserve "Saline di Trapani e Paceco" (Crustacea, Isopoda, Oniscidea) in northwestern Sicily.

Abstract Ecosystems comprising coastal lakes and ponds are important areas for preserving biodiversity. The natural reserve “Saline di Trapani e Paceco” is an interesting natural area in Sicily, formed by the remaining strips of land among salt pans near the coastline. From January 2008 to January 2010, pitfall trapping was conducted in five sampling sites inside the study area. The community of terrestrial isopods was assessed using the main diversity indices. Twenty-four species were collected, only one of them endemic to western Sicily: Porcellio siculoccidentalis Viglianisi, Lombardo & Caruso, 1992. Two species are new to Sicily: Armadilloniscus candidus Budde-Lund, 1885 and Armadilloniscus ellipticus (Harger, 1878). This is high species richness for a single reserve in Sicily. The extended sampling period also allowed us to study species phenology. Most of the species exhibited higher activity in spring than in autumn while some species also exhibited lower activity in the summer. The species richness revealed that the study area is in an acceptable conservation status; Shannon and Pielou indices also confirmed a more or less even distribution of individuals belonging to different species.

Plant communities preferences of terrestrial crustaceans (Isopoda: Oniscidea) in a protected coastal area of southeastern Sicily (Italy)

We studied the plant communities preferences of oniscidean isopods in a protected coastal area in southeastern Sicily that is characterized by ponds, dunes and rocky coast. In total, five sites were sampled between March 2003 and February 2004 using pitfall traps. A total of 7,326 specimens were found, belonging to 23 species. The vegetation analysis, using the phytosociological method, recognized a total of 11 types of plant communities, with specific ecological features. Measuring the species richness, diversity and annual activity density (aAD) values of the terrestrial isopod communities from each sampling site revealed differences among the various plant communities. PCA analysis confirmed the correlation between isopods species and specific plant communities. Moreover our results show that the high species richness is associated with a high vegetation cover and number of plants.

Morphostructural and immunohistochemical study on the role of metallothionein in the detoxification of heavy metals in Apis mellifera L., 1758

Honey is a valuable food produced by bees from sugary substances that they gather in nature. The transformation the nectar into honey, by bees, is long and complex. Except for honey, where heavy metals are absent or are found only in traces, the bees and their products have always been considered excellent biomarkers of such contaminants. We have assumed that the absence of heavy metals in honey is due to the presence of a detoxification system in the digestive system of bees, which involves metallothioneins, proteins that have a role in the homeostatic control of essential and non‐essential metals. We have placed the beehives in three different zones: industrial, urban and rural. Investigations were carried out with ICP‐MS method for the detection of heavy metals in the guts of honey bees and honey. The metallothioneins have been identified by Immunohistochemical and Western‐blotting analisys. The investigations have shown the presence of heavy metals only in bees guts but not in honey, while the presence of metallothionein has been highlighted only in epithelium of the honey sac, demonstrating the existence of an efficient system of detoxification of heavy metals.

Metallic Nano‐Composite Toxicity Evaluation by Zebrafish Embryo Toxicity Test with Identification of Specific Exposure Biomarkers

Nanomaterials (NM) have different shapes and can be composed of different materials such as carbon, silicon, and some metals like gold, silver, and titanium. They are used as fillers, catalysts, semiconductors, cosmetics, drug carriers in medicine, energy storage systems, and antifriction coatings. NM are the parent compounds of nanoparticles (NPs), which may be divided into two groups: fullerenes and engineered nanoparticles (ENPs). After crossing the cell membrane, NPs may be stored in vesicles, mitochondria, and additional organelles within epithelial cells. They may generate reactive oxygen species, oxidative stress, and cytotoxicity, as well as denaturation of proteins, apoptosis, and necrosis. Nowadays, new toxicological data are required to assess the potential exposure of the environment and human beings to pollutants. The aim of the present investigation is to evaluate the toxicity of the metallic nano‐composite by the zebrafish embryo toxicity test (ZFET). The methods described here can be easily adapted to other nanocomposites or nanomaterials with some variations.

The influence of coastal zonation and meteorological variables on terrestrial isopod populations: a case study in western Sicily (Italy)

Abstract Because of their biological and ecological characteristics terrestrial isopods are considered as bioindicators of ecosystem health and several studies have shown that their distribution and abundance are influenced by environmental factors, such as weather, soil texture, composition and vegetation structure. However, few quantitative data are available on the relationship between single species of terrestrial isopods, meteorological variables and coastal zonation. This study aims to clarify relationships between terrestrial isopod populations, coastal zones and weather conditions of a protected area in Sicily. The terrestrial isopods were sampled using pitfall traps, and we verified the association between each species abundance and three different (lower, medium and upper) coastal zones. Furthermore, we analyzed correlations between isopod abundances and meteorological conditions (temperature and precipitation). The results showed a close relationship between some isopod species and coastal zone types, as well as a positive correlation of most of the species abundances with temperature and a negative one with precipitation.

A sampling optimization analysis of soil‐bugs diversity (Crustacea, Isopoda, Oniscidea)

Abstract Biological diversity analysis is among the most informative approaches to describe communities and regional species compositions. Soil ecosystems include large numbers of invertebrates, among which soil bugs (Crustacea, Isopoda, Oniscidea) play significant ecological roles. The aim of this study was to provide advices to optimize the sampling effort, to efficiently monitor the diversity of this taxon, to analyze its seasonal patterns of species composition, and ultimately to understand better the coexistence of so many species over a relatively small area. Terrestrial isopods were collected at the Natural Reserve “Saline di Trapani e Paceco” (Italy), using pitfall traps monthly monitored over 2 years. We analyzed parameters of α‐ and β‐diversity and calculated a number of indexes and measures to disentangle diversity patterns. We also used various approaches to analyze changes in biodiversity over time, such as distributions of species abundances and accumulation and rarefaction curves. As concerns species richness and total abundance of individuals, spring resulted the best season to monitor Isopoda, to reduce sampling efforts, and to save resources without losing information, while in both years abundances were maximum between summer and autumn. This suggests that evaluations of β‐diversity are maximized if samples are first collected during the spring and then between summer and autumn. Sampling during these coupled seasons allows to collect a number of species close to the γ‐diversity (24 species) of the area. Finally, our results show that seasonal shifts in community composition (i.e., dynamic fluctuations in species abundances during the four seasons) may minimize competitive interactions, contribute to stabilize total abundances, and allow the coexistence of phylogenetically close species within the ecosystem.

Habitat and ecological diversity influences the species-area relationship and the biogeography of the Sicilian archipelago’s isopods

Abstract Terrestrial isopods are a well-studied invertebrate taxon in Sicily and in the surrounding islands (Maltese archipelago included). During the last 30 years their systematics, ecology and biogeography have been analysed by many authors. The size and the diverse geological origin of the Sicilian archipelago represents an ideal open laboratory in which to study some biogeographical patterns, such as the species-area relationship (SAR). Since many species show limited adaptation to broad physiological conditions and low mobility, and, therefore, their active dispersion is very slow, SAR can be a useful means to examine biogeographical patterns of isopods. Here we analyse their biogeography and whether there is a relationship between the area and the habitat variability of the island surveyed, and whether these factors have an either direct or coupled influence on species richness and ecology. Moreover, we evaluate a potential relationship between Isopoda species richness and the distance from the centre of dispersion (Sicily). Finally, we test for a difference in species and habitat richness between volcanic and non-volcanic islands. Our results show a positive correlation between the area and the habitat, more significant than that between the area and the species, leading us to speculate that habitat diversity has an influence on the SAR of isopods. We find a significantly higher richness of both species and habitats on non-volcanic islands. Finally, our analysis confutes the hypothesis that the number of isopod species on the archipelago’s islets declines with the distance from Sicily. We suggest some potential explanations.