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The occurrence of the Chinese pond mussel Sinanodonta woodiana is reported for the first time in the Molise region (Southeast Italy). Details of the mussel’s invasion history in Italy are also given. A total of 24 S. woodiana specimens were collected after a long drought period in October 2017 from an emerged beach on the southwest side of the Guardialfiera artificial lake and their main morphometric features were quantified. No young individuals were found, only large adults, whose survival could ensure population subsistence in more suitable environmental conditions. The present study provides evidence of a massive die-off affecting invasive bivalves during an extreme climatic event, producing decaying biomass with negative impacts on the water quality of the lake. Further investigations of the population dynamics of this species and the environmental quality of the water body are needed to develop an appropriate management plan in relation to the ecosystem services it delivers.

Le previsioni di un incremento delle temperature globali e di un conseguente innalzamento del livello del mare nei prossimi decenni/secoli ha sollevato interrogativi riguardo la risposta dei parassiti al cambiamento climatico antropogenico. In particolare questo lavoro prevede lo studio delle tracce di parassitismo da trematodi digenei Gymnophallidae che si manifestano in forma di pits, depressioni ovali con bordi rialzati all’interno delle valve di esemplari fossili di Abra segmentum, per verificare se questo tipo di lesione sia presente (e con quale frequenza) anche negli esemplari attuali comparandole con quelle evidenziabili in A. segmentum datati fino a circa 9000 anni fa. Gli esemplari viventi di A. segmentum studiati in questa ricerca sono stati campionati in tre aree salmastre costiere, Piallassa Baiona (RA), Saline di Cervia (FC) e Laguna di Lesina (FG). Le località scelte rappresentano habitat ideali per la specie A. segmentum, nonché analoghi moderni degli ambienti olocenici in studio. Per ogni sito sono state delimitate aree di 25 m2 e, per i siti romagnoli, raccolti ~200 esemplari vivi di A. segmentum durante Giugno - Luglio 2017, mentre nella Laguna di Lesina oltre ai campionamenti estivi consistenti in ~200 esemplari vivi, erano stati prelevati ulteriori ~100 esemplari anche durante Novembre - Dicembre 2016. I bivalvi sono stati aperti ed esaminati allo stereomicroscopio; il tessuto molle è stato rimosso dalle valve e pressato tra due vetrini portaoggetto per l’individuazione di sporocisti, cercarie e metacercarie di trematodi digenei, con particolare attenzione a queste ultime che sono ritenute responsabili della formazione dei pits sulle valve interne (Campbell, 1985, Cremonte & Ituarte, 2003). Gli elementi parassitari riscontrati venivano fissati in etanolo 70%, sia previo isolamento sia all’interno dei tessuti, per la successiva identificazione morfologica e molecolare. I risultati indicano valori di prevalenza di stadi larvali di trematodi digenei molto variabili e talvolta molto elevati nella Laguna di Lesina (tra 6 e 61%), e valori di prevalenza inferiori e con range meno ampio in quelli delle Saline di Cervia (tra 23 e 34%) e Piallassa Baiona (tra 7 e 17%). Quando riferiti agli esemplari con sole metacercarie la prevalenza media nella laguna di Lesina scende al 21%±5%, 20%±5% per le Saline di Cervia e 7%±3% per Piallassa Baiona. A livello stagionale, nella Laguna di Lesina i campioni invernali hanno presentato prevalenza inferiore rispetto a quelli estivi, con valore massimo di 6%. L’analisi dei pits sulle valve degli esemplari attuali parassitati ha messo in luce come gli esemplari di A. segmentum viventi sviluppino accenni di pits molto meno marcati rispetto alle controparti fossili, sebbene sia da evidenziare come l’identificazione dei parassiti reperiti nel corso della presente indagine sia ancora in corso. Il confronto preliminare tra i valori di prevalenza dei pits in A. segmentum fossili riportati da Scarponi et al. (2017) evidenzia come mediamente la presenza dei pits nel record fossile durante le fasi di rapido innalzamento del livello marino appaia più elevata rispetto agli esemplari attuali. I risultati ottenuti nel corso di questa indagine nel confronto tra Abra segmentum fossili e attuali, pone l’accento sull’importanza di ulteriori approfondimenti sul rischio che l’aumento del livello marino causato dal riscaldamento globale possa in futuro, come già accaduto in passato, provocare una maggior diffusione e patogenicità di parassiti marini con effetti negativi sugli ecosistemi interessati.

Lo studio e monitoraggio delle specie alloctone in ambiente marino è un elemento di primaria importanza per lo sviluppo di politiche ambientali. Tuttavia, soprattutto con gli invertebrati, non è sempre semplice capire se una specie sia realmente alloctona, o non rappresenti piuttosto un’entità nativa la cui presenza è stata sottostimata. In questo studio si è scelto di studiare la diffusione in Mediterraneo di Aricidea fragilis Webster, 1879, una specie tipica dell’Atlantico occidentale, di cui sono note alcune segnalazioni storiche (Strelzov, 1973; Laubier&Ramos, 1974), ma che negli ultimi anni è stata oggetto di un’ampia espansione demografica principalmente nel Mar Adriatico. Sulla base di dati storici e di dati inediti, con considerazioni sull’ecologia della specie, si tenta di discutere se A. fragilis debba essere considerata alloctona o nativa nei mari italiani. Si tratta, in questo caso, della prima possibile introduzione di un polichete della famiglia Paraonidae.

The blue crab Callinectes sapidus (Rathbun, 1896), a native to western Atlantic coasts, is widely recorded in various Mediterranean regions, including the Gargano lagoons in the Adriatic Sea. This study investigated selected biological traits of Callinectes sapidus females in the Lesina and Varano lagoons during their breeding migration to more saline waters. In total, 19 individuals of Callinectes sapidus, 15 females and four males, were collected in the lagoons near the mouths of the seaward channels. The specimens' Carapace Width ranged from 115 to 230 mm, classifying them as medium to large crabs. In Varano lagoon in April and May 2014, two ovigerous females with egg masses of 63.39 g and 11.65 g respectively were captured. This represents the first record of ovigerous females of C. sapidus in this lagoon. The average Gonado-Somatic Index was 2.91 +/- 1.82 and 1.65 +/- 0.65 for the specimens captured in Varano and Lesina lagoons, respectively. The average Hepato-Somatic Index was 3.88 +/- 0.80 and 4.22 +/- 0.31 for specimens captured in Varano and Lesina, respectively. Egg diameter ranged between 0.23 and 0.35 mm. Histological analysis of gonads showed stages from III to V, with individuals in emission or postissuance stages. This study presents evidence of the establishment of C. sapidus populations in Varano lagoon in the south-west Adriatic Sea and provides additional information on this species in the Lesina and Varano lagoons.

The zooplankton composition of Lake Varano has been studied from June 2007 to May 2008 considering three sampling stations (western, central, eastern). A total of 55 zooplankton categories were recognised, with medusae Aurelia aurita as the main macroscopic species; 43 of them occurred in less than 50% of the 71 samples collected, highlighting the seasonal aspect of the community. The remaining 12 categories, present in more than 50% of samples, were numerically dominated by the copepod ‘Non Indigenous Species’ Acartia tonsa (reported here for the first time in the lake), which occurred throughout the year. Maximal abundance of zooplankton was recorded in the eastern sampling station, while the lowest values were recorded in the central one. The statistical analysis of data allowed us to establish a not sharp separation of the three sampling stations, apart from isolated dates. The present zooplankton assemblage showed that about 40% of its components differed from those recorded in a study of 18 years before. This last comparison is not easily referable to the ongoing climate warming (the dominant species are of cold temperate origin) and analysis of uninterrupted time series could be useful to understand the underlying reasons.

1 - In this study recent changes of the distribution of three phanerogam species (Ruppia cirrhosa, Cymodocea nodosa, and Nanozostera noltii) were studied in the Orbetello lagoon, a meso-eutrophic and human stressed ecosystem. 2 - The aim was: I) to produce SURFER distributions maps, and II) to statistically evaluate significant changes in the spatial distribution taking into account two different factors (basin and year). For these reasons, percentage of coverage (CP) of each species was estimated in 38 sites equally distributed inside the Eastern and Western basins both in summers 2003 and 2009. 3 - The geostatistical maps evidenced changes in phanerogams distribution during the studied period but only variations observed for the N. noltii species at basin level resulted significant on a statistical basis. Significant differences at basin level were also obtained by the multivariate analysis. These results might be explained by the different ecological characteristics existing between Western and Eastern basins. © 2009 University of Salento - SIBA.

The results presented in this work are related to an anoxic event occurred in Lesina lagoon (SE Italy) in summer 2008. The main aim is to describe the temporal dynamics of physicochemical characteristics of both sediment and overlaying water inside and outside the critical area. Nine sampling campaigns were carried out on a weekly basis. At each occasion T, S, pH, DO, nutrients and chl a were measured in water and TOC, TN, TP, TFe and ORP were performed on superficial sediments. Multivariate analysis was used in order to evaluate differences between inner and outer sites and assess the relationships between sediments and overlaying water. The factor "location" was significant for the observed physicochemical differences, as also tested by Anosim test one-way which supported evident differences in sediments (R = 0.599, p = 0.01%) and water (R = 0.381, p = 0.01%) between inner and outer sites. Wide fluctuations of oxygen and chlorophyll a were observed in the sites located within the anoxic area, with a peak of biomass of 180 µg.L-1 followed by saturation of oxygen higher than 100%. PCA analysis on sediment variables indicated a clear separation between inner and outer sites along the first axis (PC1) strongly associated with TOC, TN and ORP. A relationship between the content of TP in sediments and TP in water, followed by a phytoplanktonic bloom, was observed and confirmed by statistical correlation methods based on Spearman rank (Rho = 0,569, significance level of 0.01%).

Lo scopo del lavoro è stato quello di descrivere lo stato ecologico della Sacca Orientale della laguna di Lesina (FG), considerando la comunità macrobentonica e la vegetazione sommersa. Sono stati fatti campionamenti stagionali (2010) in 13 stazioni. In ogni stazione sono state misurate T°C, Salinità e O% dell'acqua e prelevato mediante box-corer (0.0225m2) la macrofauna bentonica e la vegetazione. Il campione, separato dalla vegetazione è stato setacciato in situ, con setaccio di 1 mm. Per ogni stazione è stata rilevata la biomassa umida (gr/m2) e le specie vegetali, l'abbondanza (ind/m2), la biomassa umida (gr/m2) e calcolato gli indici strutturali della comunità bentonica. Per la vegetazione sono state identificate 8 categorie, 7 determinate a livello di specie e 1 a livello di genere. Della macrofauna bentonica sono stati identificati 16 taxa, 15 a livello di specie e 1 a livello di genere, raggruppati in 13 famiglie. Il numero maggiore di famiglie apparteneva ai crostacei (4). Il gruppo più abbondante sono stati i gasteropodi (50%), seguito dai bivalvi (21%) e crostacei (11%). I bivalvi e i crostacei sono stati i più ricchi di specie (4). L'abbondanza media non ha mostrato differenze significative sia tra i campionamenti che tra le stazioni (Anova, p non significativo). Differenze significative tra i mesi sono state osservate per l'indice di Shannon (p

Soft bottom macrozoobenthic distribution, as well as its composition, biomass and diversity were studied at 9 stations in the Gulf of Manfredonia. Polychaeta were numerically the dominant component (71%), followed by Crustacea (21%) and Bivalvia (2%). The highest biodiversity was observed at the stations in near-shore of the study area.

In Varano lagoon (Puglia, Italy) the bivalve Loripes lacteus (Linnaeus, 1758) constitutes the most abundant species among the organisms of the benthic macrofauna. This work presents the results of five years (from 2001 at 2006) of observations on the abundance, size/age population structure and spatial distribution of this species within the basin (6500 ha). L. lacteus is one of the most common and frequent bivalve species in Mediterranean lagoons. It typically occurs in reduced sediments where it is able to live at low oxygen concentration due to a particular respiratory pigment haemoglobin. Lucinid bivalves house symbiotic, sulphur-oxydizing chemoautotrophic bacterias in their gills, which contribute substantially to their nutrition. 2 - The design was to perform two sampling campaignes on yearly basis during the intermediate seasons (Spring and Autumn), when possible. Each sampling was realized collecting 53 sampling units taken from 53 stations distributed regularly over the lagoon surface. Each sampling unit consisted in all the individuals contained in a solid 15 x 15 x 20 cm of sediment and held on 1 mm mesh. 3 - Growth patterns were determined with the Bhattacharya method which uses modal progression analysis from size frequency distribution. 4 - The results showed a spatial distribution of L. lacteus which occurred in patches and changed among samples. The population analysis showed two modal classes for each sampling time. 5 - L. lacteus is an “r” strategy species with small size, brief life cycle, with great capacity of recovery after environmental crises.

The purpose of this paper is to assess the present status of a Mediterranean lagoon (Varano lagoon, Italy), basing on nutrient and chlorophyll a data. A water sampling in Varano lagoon was performed at 7 fixed stations from February 2004 to July 2005, collecting surface water samples to analyse ammonia, nitrite, nitrate, soluble reactive phosphorus (SRP) and soluble reactive silica (SRSi), chlorophyll a (chl a) and total suspended solids (TSS). Spatial and temporal distributions of chemical and biological parameters in Varano lagoon were examined to accomplish the goal of this study. Statistical tests were used to investigate the correlations between analysed variables and to characterize, from a spatial and temporal point of view, the lagoon in relation to each variable. Ammonia and nitrate did not showed good correlation (P

The results presented in this work are part of a pilot project aimed at the evaluation of the potential biodiesel production from algal biomass. Specifically, macroalgal and phytoplanktonic biomass of two Italian lagoon, Orbetello (north Tyrrhenian Sea) and Lesina (south Adriatic Sea), regarded as highly productive and eutrophic, were monitored in spring and summer 2011 and 2012. The study has been divided in two main sections. Firstly, a general qualitative outline of the submerged vegetation distribution by visual census techniques was conducted. Secondly, macroalgae and water samples for chlorophyll a determination were collected in order to study the primary production (in Kg.m-2 and ?g.L-1 for macroalgae and phytoplankton, respectively). Accordingly the lagoons have been divided into transects oriented according to the direction NS and WE. We obtained a total of 18 transects oriented in NW-SE direction in the Orbetello (8 in the western basin and 10 in the eastern basin) and 13 in the Lesina (10 of them in the "Sacca Orientale"). At the same time, physico-chemical parameters were measured by multiparametric probe. The results show a basic difference between the two systems, with a productivity shift towards phytoplankton biomass in Lesina and macroalgae in Orbetello. In Lesina, mean concentrations of chlorophyll a were 2.97 ± 3.63 ?g.L-1 (spring, with maximum of 15.27??g.L-1) and 2.36 ± 2.60 ?g.L-1 (summer, with peak of 12??g.L-1), while macroalgal biomass ranged from 1.9 to 2.6 kg.m-2 for both observation periods. Conversely, in Orbetello lagoon mean phytoplanktonic chlorophyll a did not exceed the level of 0.51 ±0.31 ?g.L-1 in spring and 0.81 ± 0.70 ?g.L-1 in summer (with maximum of 3.21 ?g.L-1), while biomass of submerged vegetation was always an order of magnitude greater. In particular, macroalgal biomass was higher in the western basin than in the Eastern one with mean values that increased from spring (28.2 Kg.m-2) to summer (66.1 kg.m-2). This study indicates that the high macroalgal production in Orbetello lagoon could be evaluated for biodiesel production, while in Lesina the macroalgae distribution is more casual e quantitatively less abundant.

1 -In this study recent changes of the distribution of three phanerogam species (Ruppia cirrhosa, Cymodocea nodosa, and Nanozostera noltii) were studied in the Orbetello lagoon, a meso-eutrophic and human stressed ecosystem. 2 -The aim was: I) to produce SURFER distributions maps, and II) to statistically evaluate significant changes in the spatial distribution taking into account two different factors (basin and year). For these reasons, percentage of coverage (CP) of each species was estimated in 38 sites equally distributed inside the Eastern and Western basins both in summers 2003 and 2009. 3 -The geostatistical maps evidenced changes in phanerogams distribution during the studied period but only variations observed for the N. noltii species at basin level resulted significant on a statistical basis. Significant differences at basin level were also obtained by the multivariate analysis. These results might be explained by the different ecological characteristics existing between Western and Eastern basins.

In this work the results of a test breeding of Crassostrea gigas (Thun.) in Varano lagoon, performed from 2006 to 2007, are presented. Minimum average size with trade interest was 6 cm and it was observed for six months. The results obtained suggest good prospects for the oyster culture reintegration into the activities of the aquaculture brackish from reassess.

1. Introducing more or less voluntary alien species is now recognized worldwide as one of the most 1 - serious biological threats to biodiversity. The brackish-water lakes of the Lesina and Varano (Apulia, Adriatic Sea), where in recent years (2000-2007) the presence of exotic species is increasingly reported by local fishermen, have not been spared this phenomenon. 2. The two biotopes are connected with the Adriatic Sea by two artificial channels. In this paper a list 2 - of alien species found in the two brackish basins in recent years was described. 3. The following 6 species were reported: Oreochromis niloticus niloticus (Linnaeus, 1758) 3 - (Actinopterygii, Perciformes, Cichlidae), Callinectes sapidus (Rathbun, 1896) (Arthropoda, Crustacea, Decapoda, Portunidae), Procambarus clarkii (Girard 1852) (Arthropoda, Crustacea, Decapoda, Cambaridae), Musculista senhousia (Benson in Cantor,1842) (Mollusca, Bivalvia, Mytilidae), Rapana venosa (Valenciennes, 1846) (Mollusca, Gastropoda, Muricidae), Dyspanopeus sayi (Smith, 1869) (Arthropoda, Crustacea, Decapoda, Xanthidae). 3. The presence of Oreochromis niloticus niloticus and Procambarus clarkii seemed to be linked to the 4 - accidental release from aquaculture activities present in the sourronding land, while the presence of Musculista senhousia, Rapana venosa and Dyspanopeus sayi was probably due to the introduction into the lake of the juvenile mussels coming from the northern Adriatic sea. The place of origin of other species is not clear.

1-The scope of our work was to assess the ecological status of Lesina lagoon on the South Adriatic coast of Italy according to the biological priorities expressed by the directives of the government, priorities which can be summed up in the key words of bionomics, biomass and biodiversity. 2 - Our method was based on the characteristics of the sessile benthic macrofauna considered to be indicative of environmental status. We developed a biotic index (›) that grades from 1 to 10 the rising quality of the environment. The data required for applying the index, i.e. spatial distribution (Zonation), biomass (g ww/m2) and number of species of the benthic macrofauna, were obtained from samples of sediment taken at systematically distributed stations over the entire surface of the lagoon. Samples were taken in spring and again in autumn. 3 - Our first assessment in Jan. 1993 gave 8.48, a high value. No samples were taken in 1994 but quality probably remained high because in Nov. 1995 the index gave 7.86. In 1996 quality must have begun to decline because although we took no sample in that year, in May 1997 the index was 6.14, which is very low for spring, when quality is normally high. The situation did not improve until August 1998 when the index rose to 7.59. From then on till our last assessment in Oct. 2003 the environmental quality of Lesina was at a stable high, the index registering values above 7.00 with a peak of 8.15 in Aug. 1999. 4 - The index values that we registered closely coincided with the opinion on the state of the environment given by experienced fishermen whose livelihood depends on the quality of the lagoon.

Varano lagoon, located on the northern coast of the Gargano promontory (Southern Adriatic Sea), Italy, is a shallow body of water, with a depth ranging from