The present paper deals with the description of specimens of a new species of Pseudobranchiomma Jones, 1962 collected from the Sea of Marmara between 50 and 100 m depths, a genus that, up to now, is represented within the Mediterranean area by only one species. The new species is mainly characterized by having radioles without serrations, well-developed paired compound eyes on radioles, absence of dorsal pinnular appendages, minute interramal eyespots appearing after chaetiger 5, and pointed ventral sacs and lappets. The morphological features of the new s

Sperm ultrastructure and some steps of spermatogenesis of the serpulids Hydroides dianthus, Serpula vermicularis and Vermiliopsis infundibulum are reported. In all the species examined the germinal cells originated from a germinative epithelium associated to blood vessels in the intersegmental septa. The spermatocytes were irregular in shape with a large nucleus and a thin cytoplasmic layer. In early spermatids in which the nucleus gradually condensed, a developed endoplasmic reticulum and some electron-dense bodies were observed. The nucleus was dehydrated in the late spermatids and assumed a cylindrical shape. In all the examined species, the morphology of the ripe spermatozoa can be ascribed to the ect-aquasperm type. The acrosome had a simple cup shape in V. infundibulum, whilst it was more developed extending laterally to the nucleus in H. dianthus, and cup-shaped with a swelling towards the nucleus in S. vermicularis. When the morphology of the serpulid spermatozoa was superimposed on a phylogenetic scheme, some trends could be highlighted. Although the paucity of data on serpulid spermatozoa ultrastructure at present prevents any phylogenetic inference, the comparison of acrosome ultrastructure within a group having similar reproductive strategies showed an increase in the internal complexity of the acrosome.

Metabolic rate determines the physiological and life-history performances of ectotherms. Thus, the extent to which such rates are sensitive and plastic to environmental perturbation is central to an organism’s ability to function in a changing environment. Little is known of long-term metabolic plasticity and potential for metabolic adaptation in marine ectotherms’ exposed to elevated pCO2. Consequently, we carried out a series of in situ transplant experiments using a number of tolerant and sensitive polychaete species living around a natural CO2 vent system. Here, we show that a marine metazoan (i.e. Platynereis dumerilii) was able to adapt to chronic and elevated levels of pCO2. The vent population of P. dumerilii was physiologically and genetically different from nearby populations that experience low pCO2, as well as smaller in body size. By contrast, different populations of Amphiglena mediterranea showed marked physiological plasticity indicating that adaptation or acclimatization are both viable strategies for the successful colonization of elevated pCO2 environments. In addition, sensitive species showed either a reduced or increased metabolism when exposed acutely to elevated pCO2. Our findings may help explain, from a metabolic perspective, the occurrence of past mass extinction, as well as shed light on alternative pathways of resilience in species facing ongoing ocean acidification.

We present a contribution to the knowledge of marine and brackish water alien species (infraspecific taxa included) recorded along the Italian coasts. The Italian Peninsula, with over 7,000 km of coastline, is located in the center of the Mediterranean Sea, splitting the Western and the Eastern basins. Data were collected from published material, mostly authored by the experts of different marine taxa participating in the "Allochthonous Species Group" of the Italian Society of Marine Biology (SIBM). The data have been reviewed according to the taxonomic expertise of the authors and are organized in a referenced database containing information on each species about: distribution along Italian coasts, the native range, most probable vectors of introduction, population status and impact. The total number of marine alien species recorded along Italian coasts during the selected time period 1945-2009 is relatively high: 165 species, in many cases native from tropical regions of the world. Most of them were introduced in the 1980s and 1990s, whereas in the last few years the number of new records has decreased. The highest number of alien species has been observed in the northern Adriatic Sea, particularly in the Lagoon of Venice, which is the main hotspot of introduction. Of the total number of species, 46% was unable to establish resident populations in the Italian seas; 15% (24 species) rapidly increased their populations and extended their geographical range, consequently they may be considered invasive species.

The state-of-art on alien species in the Mediterranean Sea is presented, making distinctions among the four subregions defined in the EU Marine Strategy Framework Directive: (i) the Western Mediterranean Sea (WMED); (ii) the Central Mediterranean Sea (CMED); (iii) the Adriatic Sea (ADRIA); and (iv) the Eastern Mediterranean Sea (EMED). The updated checklist (December 2010) of marine alien species within each subregion, along with their acclimatization status and origin, is provided. A total of 955 alien species is known in the Mediterranean, the vast majority of them having being introduced in the EMED (718), less in the WMED (328) and CMED (267) and least in the Adriatic (171). Of these, 535 species (56%) are established in at least one area.

Direct and indirect biotic interactions driving community structure, can be positive, increasing the fitness of both partners, or negative, often increasing the fitness of only one of the participant to the interaction. Moreover, partner interaction may produce an integration among them, thus giving rise to an association defined as symbiosis, with parasitism and mutualism as the two extremes of a symbiotic continuum. In the past, negative interactions have been considered more widespread within communities and responsible for most of their structures. They have also been studied by an experimental approach. By contrast, cooperative interactions have mainly approached with a descriptive aspect. Negative interactions are more abundant in benign environments, whilst positive ones develop according to the environmental harshness with different organisms cooperating to cope environmental stress. Both parasitism and mutualism can evolve from a commensal interaction depending from the ecological context and have a different role in promoting evolution. In turn commensalism can evolve from epibiosis, a widespread phenomenon in marine benthic environment where the high spatial competition promotes the overgrowth of organisms. Therefore epibiosis is the starting point for further evolution of different kind of interactions. We describe some examples of mutualisms in marine environment, underlining how such interactions can lead to the increase of biodiversity.

A study on macrobenthos of Acquatina Lake, a transitional water basin, was performed in order to evaluate its present status and detect any faunistic changes after the digging of a larger connection with the open sea that has improved the hydrological conditions. A total of 5029 individuals belonging to 51 taxa were collected. Molluscs were taxonomically the richest group, but polychaetes were the most abundant due to the high abundance of Heteromastus filiformis. The sites representing two extremes of the biotope in terms of both the salinity gradient and the distance from the sea had the most variable assemblages, while the central area showed a more homogeneous faunal composition. This was due to the different distribution patterns of molluscs and polychaetes: the former seemed to be more influenced by salinity, while the latter were also influenced by oxygen saturation. The comparison between the present and historical data showed the increase of polychaete diversity, the change in the dominant taxa (from Naineris laevigata to H. filiformis) and the disappearance of some opportunistic forms (e.g. Capitella capitata). Changes in the salinity gradient and the improvement of trophic conditions, possibly enhanced by biotic interactions (e.g. possible competition between the two capitellids H. filiformis and Notomastus latericeus), may have led the polychaete assemblage towards the new equilibrium.

The first observations on the reproductive biology of the alien polychaete Branchiomma bairdi (McIntosh, 1885) (Sabellidae) in the Mediterranean Sea are provided as well as additional Mediterranean records of the species, which can help to understand its introduction and spreading. Re-examination of the specimens from Miseno harbour (Tyrrhenian Sea, Italy) revealed the presence of B. bairdi in the central-Mediterranean since September 2004. The histological study of individuals collected in Malta revealed that the species is a simultaneous hermaphrodite, developing male and female gametes in the same body segments; embryos are brooded inside the parent tube. However, there is also evidence of asexual reproduction. The species shows a different reproductive pattern from the previously reported population from the eastern-Pacific; this demonstrates its great plasticity and adaptability. Branchiomma bairdi has an invasive behaviour, colonizing large areas in relatively short-time, and reaching relatively high densities (c.a. 50 individuals/m2). Its expansion to several Mediterranean localities is largely a consequence of the high capacity of this species to colonize extremely different habitats and substrates, the occurrence of sexual and asexual reproductive strategies, and the combination of both. Furthermore, B. bairdi appears to be particularly abundant in confined areas and areas degraded due to anthropogenic impacts. Finally, our findings strongly suggest that the pathway of introduction in the Mediterranean, previously hypothesized as the Suez Canal (Lessepsian migration), is most likely via the Strait of Gibraltar.

The excessive release of bacterial pathogens from animal waste into the aquaculture environment has become a major concern for the aquaculture industry. The biological filtration by macroinvertebrates contributes to water purification as a result of the bacterioplankton removal from the water. The filterfeeder polychaete Sabella spallanzanii is known for its ability to accumulate bacteria from the marine environment. In the present study we evaluated the survival, growth and capability of this species to remove several bacterial groups from aquaculture waste in order to ascertain its employment as bioremediator in a farming scenario coupled with the conversion of the wastes into polychaete proteinrich biomass of potentially marketable value. In comparison to other technologies, the employment of S. spallanzanii in waste treatment represents a more attractive option to reduce bacterial loads.

Vibrios are among the most abundant culturable microbes in aquatic environments. They can be either free-living in the water column or associated with several marine organisms as mutualists, saprophytes, or parasites. In the present study we analysed vibrios abundance and diversity in the mucus of the polychaete Myxicola infundibulum, complementing culture-based with molecular methods. Vibrios reached 4.6 × 103 CFU mL-1 thus representing a conspicuous component of the heterotrophic culturable bacteria. In addition, luminous vibrios accounted for about 60 % of the total culturable vibrios in the mucus. The isolates were assigned to: Vibrio gigantis, Vibrio fischeri, Vibrio jasicida, Vibrio crassostreae, Vibrio kanaloae, and Vibrio xuii. Two Vibrio isolates (MI-13 and MI-15) may belong to a new species. We also tested the ability of the Vibrio isolates to grow on M. infundibulum mucus as the sole carbon source. All strains showed appreciable growth in the presence of mucus, leading us to conclude that this matrix, which is abundant and covers the animal entirely, may represent a microcosm and a food source for some bacteria, playing a crucial role in the structuring of a mucus-associated beneficial microbial community. Moreover, the trophic relationship between vibrios and M. infundibulum mucus could be enhanced by the protection that mucus offers to vibrios. The results of this study represent a contribution to the growing evidence for complex and dynamic invertebrate-microbe associations present in nature and highlight the importance of exploring relationships that Vibrio species establish with marine invertebrates

In the marine environment, sessile invertebrates have developed an impressive array of mechanisms to avoid predation, bacterial exploitation, and epibiotic overgrowth. In the present study we investigated several defensive strategies adopted by six sabellids: the hard bottom species Sabella spallanzanii (Gmelin, 1791), Branchiomma luctuosum Grube, 1869, Branchiomma bairdi (McIntosh, 1885), and Sabellastarte spectabilis (Grube, 1878), and the soft bottom species Myxicola infundibulum (Renier, 1804), and Megalomma lanigera (Grube, 1846), which have different morphological characteristics and geographical distribution. We examined and compared some defensive features such as branchial crown toughness, tube structure and strength, amount of released mucus, and antibacterial lysozyme-activity in the mucus. The investigated species utilize a combination of defence and deterrence strategies that seems to be related to the colonized habitat. Tube strength was, higher in the hard bottom species compared with the soft bottom ones, where the tubes are generally buried and protected within the sediment. Branchial crown appeared stronger and resistant in hard bottom species, except for S. spallanzanii, which is the species showing the strongest tube. Sabella spallanzanii, M. infundibulum and S. spectabilis secreted high amount of mucus with high lysozyme-like activity. By contrast, B. luctuosum, B. bairdi, and M. lanigera produced low amounts of mucus exerting lower antibacterial activity.

To prevent over-exploitation of global fish stocks by the aquaculture industry, interest is growing in the identification of nontraditional species with potential value as fish feed. In this study, we investigated the biochemical composition of the polychaete Sabella spallanzanii. Its elemental composition, gross protein and proximate composition, amino acid composition, total lipid and fatty acid content, glycosaminoglycan (GAG) content and the extent of polychlorinated biphenyl contamination were determined over an annual cycle. Sabella spallanzanii showed particularly high gross protein (54.8 +/- 5.8%) and gross energy (4.89 +/- 0.5 kcal/g) content. All samples had high concentrations of Na, K, Ca, and Cl. Saturated fatty acids were higher than monounsaturated and polyunsaturated ones. A low -6/-3 ratio (1.7) was recorded. Our results suggest that S. spallanzanii can be used as a dietary supplement for farmed fish. The high concentrations of certain amino acids that improve potential palatability for many farmed fish species suggest that S. spallanzanii extracts can be used in artificial fish diets as an attractant. A further original aspect highlighted by this study is the high concentration of GAGs, which are useful in pet nutrition and also in the nourishment of farmed fish with a partially cartilaginous skeleton.

The general aim of setting up a central database on benthos and plankton was to integrate long-, medium- and short-term datasets on marine biodiversity. Such a database makes it possible to analyse species assemblages and their changes on spatial and temporal scales across Europe. Data collation lasted from early 2007 until August 2008, during which 67 datasets were collected covering three divergent habitats (rocky shores, soft bottoms and the pelagic environment). The database contains a total of 4,525 distinct taxa, 17,117 unique sampling locations and over 45,500 collected samples, representing almost 542,000 distribution records. The database geographically covers the North Sea (221,452 distribution records), the North-East Atlantic (98,796 distribution records) and furthermore the Baltic Sea, the Arctic and the Mediterranean. Data from 1858 to 2008 are presented in the database, with the longest time-series from the Baltic Sea soft bottom benthos. Each delivered dataset was subjected to certain quality control procedures, especially on the level of taxonomy. The standardisation procedure enables pan-European analyses without the hazard of taxonomic artefacts resulting from different determination skills. A case study on rocky shore and pelagic data in different geographical regions shows a general overestimation of biodiversity when making use of data before quality control compared to the same estimations after quality control. These results prove that the contribution of a misspelled name or the use of an obsolete synonym is comparable to the introduction of a rare species, having adverse effects on further diversity calculations. The quality checked data source is now ready to test geographical and temporal hypotheses on a large scale

Bispira polyomma sp. nov. is described. The taxon was recently found on the SW coast of The Netherlands (NE Atlantic), and could not be referred to as any previously described species of the genus Bispira. The area has been thoroughly investigated in the past, therefore we hypothesize the species is a new introduction to The Netherlands. The tubeworm is able to settle massively on all kinds of hard substrates, is eurythermal and able to withstand slight pollution, and therefore wider dispersal is a possibility to reckon with. For this reason we give a taxonomic species description even though the genus needs further revision. Presently the taxon has been observed only near Yerseke, a centre of shellfish culture and trade with a marina. The taxon was found in 2010. Subsequent surveys revealed a very dense population had developed in 2011, with the presence of small individuals in summer 2011 suggesting successful reproduction.

The problem of the generic placement of some peculiar Mediterranean and Atlantic sabellids, showing a mixture of features found in the genera Euchone and Paradialychone, is addressed. Due to the high similarity to E. pseudolimnicola, this peculiar taxon had previously been informally named Euchone cfr. pseudolimnicola. However, while the presence of a simple pre-pygidial depression without lateral wings or a distinct ridge in the uppermost margin is similar to Dialychone and Paradialychone, the dentition of thoracic and abdominal uncini resembles that found in Paradialychone. In this study, the morphological features of Mediterranean and British material were re-examined and compared to E. pseudolimnicola specimens, and a cladistics analysis was performed. The genus Euchone appears not well defined; E. cfr. pseudolimnicola and E. pseudolimnicola are located close to each other and also located in the area of the phylogenetic tree containing the other examined Euchone species. We suggest to maintain both these taxa within the genus Euchone until a revision based on the examination of type material of all the Euchone species is performed. The new species Euchone anceps sp. nov. has been described, and the large morphological variability existing in some Mediterranean material is also addressed. An updated taxonomic key for the species of the considered genera present in Northeast Atlantic and Mediterranean Sea is also provided.

We report on fine taxonomic and functional analyses of polychaetes associated with rocky reefs along a gradient of ocean acidification (OA) at the volcanic CO2 vent system off the Castello Aragonese (Ischia Island, Italy). Percent cover of algae and sessile invertebrates (a determinant of polychaete distribution) was classified into functional groups to disentangle the direct effects of low pH on polychaete abundance from the indirect effects of pH on habitat and other species associations. A total of 6459 polychaete specimens belonging to 83 taxa were collected. Polychaete species richness and abundance dramatically dropped under the extreme low pH conditions due to the disappearance of both calcifying and non-calcifying species. Differences in distribution patterns indicate that the decreasing pH modified the structure and biological traits of polychaete assemblages independent of changes in habitat. A detailed taxonomic analysis highlighted species-specific responses to OA, with closely related species having opposing responses to decreasing pH. This resulted in an increase in the abundance of filter feeders and herbivores with decreasing pH, while sessile polychaetes disappeared in the extreme low pH zones, and were replaced by discretely motile forms. Reproductive traits of the polychaete assemblages changed as well, with brooding species dominating the most acidified zones. The few taxa that were abundant in extreme low pH conditions showed high tolerance to OA (e.g. Amphiglena mediterranea, Syllis prolifera, Platynereis cf. dumerilii, Parafabricia mazzellae, Brifacia aragonensis), and are promising models for further studies on the responses of benthic organisms to the effects of reduced pH.

Erratum to: Biol Invasions DOI 10.1007/s10530-010-9803-y

Members of only a few species of annelids are reported as being incapable of regeneration; of these, Myxicola infundibulum is the only example in the family Sabellidae. Interestingly, its congener Myxicola aesthetica exhibits noteworthy regenerative ability. Unambiguously identifying non-regenerating species is critical to reconstructing how regenerative abilities evolved within the phylum. However, studies designed specifically to assess the regenerative potential of M. infundibulum have never been performed. In this study, we aimed to confirm the lack of regeneration ability of M. infundibulum, reported previously for Atlantic specimens, or to determine the extent to which regeneration occurs. Our results showed that individuals from the Mediterranean Sea (Adriatic Sea) do undergo regeneration of lost body parts, although to a lesser extent than do other sabellids. Therefore, M. infundibulum should no longer be considered a non-regenerating species. At present, uncertainties regarding phylogenetic relationships of Sabellidae prevent inferences about the polarity of change in M. infundibulum. Since our findings are counter to those of previous studies which describe Atlantic specimens as non-regenerating, more extensive analysis is required to ascertain if they could actually belong to a different species than Mediterranean M. infundibulum, accounting for these differences in reported regenerative capacity.

Polychaete worms are known to thrive in extreme environmental conditions, however little is known about how polychaete species will respond to major climatic stressors, such as ocean acidification. Here, we examined the distribution of Fabriciidae (Annelida, Sabellida) species along a gradient of ocean acidification, caused by carbon dioxide (CO2) vent emissions in a shallow, coastal system off the island of Ischia (Tyrrhenian Sea, Italy). A total of 265 specimens of Fabriciidae, representing six species from five genera, were collected along the gradient. Most of the species were found across the entire CO2 gradient, suggesting polychaetes may have a high tolerance for ocean acidification in the future. Two of the species were new to science, and two of the genera were previously unrecorded in the Mediterranean. A full description of the new species Brifacia aragonensis sp. nov. and Parafabricia mazzellae sp. nov. is given, both of which were most abundant in the most acidified areas (pH 6.6-7.2). The geographical distribution and ecology of the new taxa, as well as of the other fabriciid species collected, is discussed. Taxonomic keys to identify the Fabriciidae species currently recorded in the Mediterranean Sea are also provided.

Although mucus plays many different roles among marine invertebrates, relatively little is known about the link between biochemical structure and function. In the present study we focused on some physical and chemical properties of the polychaete Sabella spallanzanii's mucus such as viscosity, osmolarity, electrical conductivity, elemental composition, the protein and carbohydrate content, the total lipids and fatty acid composition, and polychlorinated biphenyls (PCBs) contamination. Moreover, an antimicrobial activity of the mucus was investigated. The water content of S. spallanzanii mucus was 96.2 +/- 0.3%. By dry weight 26 +/- 1.2% was protein, 8 +/- 0.21% was carbohydrate and only 0.1% lipid, much of the remainder of the dry weight was inorganic (about 65.2%). The estimated PCBs content was <0.005 mu g g(-1). The mucus of S. spallanzanii exerted a natural lysozyme-like activity and produced in vitro the growth inhibition of Vibrio anguillarum, Vibrio harveyi, Pseudomonas aeruginosa and Candida albicans. The findings from this study contribute to improve the limited knowledge available on the mucus composition in invertebrates and have implications for future investigations related to employment of S. spallanzanii mucus as a source of compounds of pharmaceutical and marine technological interest.

The population dynamics and gametogenesis of the non-indigenous polychaete species Branchiomma luctuosum Grube, 1869 (Annelida, Sabellidae) has been investigated at three sites in the Taranto Seas (Ionian Sea, Mediterranean Sea). The species, probably introduced from the Red Sea, has been reported in the Mediterranean Sea since 1983. The species is hermaphrodite, and the reproductive season is between June and October when the largest mean size of oocytes was recorded together with the presence of mature spermatozoa. Small oocytes are present in specimens reaching about 20–25 mm in length. Therefore oogenesis seems to begin early during the first year of life, but the first reproduction can occur when the worms attain a larger size and are at least 6 months of age. Although most of the individuals reproduce seasonally within a discrete period, some individuals can reproduce in different periods during the year, the oogenesis of individuals not being synchronous. A life span of at least 2 years is highlighted, with a faster growth rate during the first months (about 20 mm per month) decreasing to about 10 mm from the 3rd to the 8th months and slowing down again after the worm reaches 100 mm in size. Some differences in growth performance are discussed, enhanced by comparing the sites located at greater depth (5–7 m) and those located at 0.5 m depth, together with the possible interactions of this alien species with the autochthonous sabellid Sabella spallanzanii.

The present work analyzed three hard-bottom and two soft-bottom species of sabellid polychaetes to determine the content of several heavy metals in their branchial crown and body. The highest concentrations of heavy metals were recorded in the hard-bottom species Branchiomma bairdi, a recent Mediterranean introduction. Differences in the metal concentrations were most notable in the high trace metal levels of the branchial crown for all the studied species. Statistical analysis showed that the Mediterranean hard-bottom species were similar each other in their heavy metal content in the body as well as in the branchial crown and appeared separated from all the other species. Arsenic and vanadium hyperaccumulation in the branchial crowns of the considered sabellid species probably acts as a deterrent for predation. The observed differences among the examined species were discussed not only at the light of habitat colonization but also in terms of the phylogeny.

Il presente lavoro ha lo scopo di far conoscere alla comunità scientifica e a chiunque sia interessato alla biodiversità del gruppo degli anellidi policheti, l’esistenza di una collezione che può essere un riferimento per studi scientifici e tassonomici. Il materiale in collezione è relativo sia a raccolte mirate, prevalentemente effettuate lungo le coste pugliesi, sia a campionamenti condotti per ricerche di tipo ecologico svolte dalla professoressa Adriana Giangrande nel corso di circa 35 anni non solo nei restanti mari italiani ma anche in altre aree del Mediterraneo ed extra-Mediterranee. La collezione è stata di recente donata al Museo di Biologia Marina “Pietro Parenzan” dell’Università del Salento e comprende 440 taxa appartenenti a 43 famiglie. La famiglia più rappresentata è quella dei Sabellidae, che include 82 taxa, cui segue quella dei Syllidae con 77 taxa. Quest’ultima è ancora oggetto di revisione.

Branchiomma bairdi is a Caribbean fan worm introduced in several localities worldwide, including the Mediterranean Sea, where the species' range has rapidly expanded. Reproduction in B. bairdi was previously investigated in both extra-Mediterranean and Mediterranean areas, but no information is available on larval development and post-larval growth. In the present article, we examined these features for a population from the Mar Grande of Taranto (Ionian Sea). The species is hermaphrodite, and fertilization occurs in situ. Mucus seems to play an important role in fertilization, and also in preserving eggs before fertilization. The trochophore stage develops within the mucus and after hatching, larvae swim for about 3 d before settlement. The trochophore showed a distinct prototroch and two red dorsolateral larval eyes. The pelagic stage takes only 96 h even though prototroch is maintained after settlement, disappearing at 5 d, when larvae showed three chaetigers and branchial crown consisted of four radioles. Some interesting observations concerning changes in the morphology of chaetae and in the number of uncini during growth are also reported, together with discussion of the development of stylodes, an important diagnostic feature in Branchiomma species identification.

In the Northern Adriatic Sea, the combination of natural and anthropogenic processes causes periodic hypoxia and anoxia, which can cause mass mortality of benthic organisms. Here, we report the results of a 20-year monitoring programme carried out after an anoxic event in 1989 that caused benthic mass mortality over an area of about 1200 km2. The recovery dynamics of the polychaete fauna was followed at three stations (including one sampled a year before the anoxic event). Samples (0.1 m2 Van Veen grab, 2-mm sieve) were collected from 1989 to 1994 and from 2003 to 2008. A total of 6519 specimens belonging to 186 species were identified. The analyses of univariate biodiversity indexes highlighted higher temporal variation of assemblage diversity in the period following the dystrophic crisis, followed by higher stability in the next decade. PERMANOVA suggested that the highest component of assemblage variation belonged to the factor year. However, differences across years varied in magnitude, depending on stations and were portrayed by non-metric multidimensional scaling plots of each year’s centroids for each of the three stations. SIMPER analysis identified the species most characterizing the assemblages in each year for each of the three stations. Our results highlight the importance of analysing long-term data sets in order to understand assemblage dynamics following strong disturbance events. Assuming the 1989 anoxia as the event determining the biodiversity change, and considering our outcomes, which suggest that the assemblages still show a pattern of non-random changes through years, our data indicate that the polychaete fauna is still recovering without having reached a pattern of among-years stability. Focusing on the biology of the species characterizing the different periods might help in understanding the ecological processes that have determined the observed pattern

The marine aquarium industry has great potential to generate jobs in low-income coastal communities creating incentives for the maintenance of a healthy coral reef, if effectively managed. In the absence of current monitoring or legislation to govern the trade, baseline information regarding the species, number and source location of animals traded is missing despite being critical for its successful management and sustainability. An industry assessment to establish the number and provenance of species of ornamental polychaetes (sabellids and serpulids) traded was undertaken across UK wholesalers and retailers. Six geographical regions exporting fan worms were identified. Singapore contributed the highest percentage of imports, but of only one worm ‘‘type’’ whereas Bali, the second largest source, supplied five different worm ‘‘types’’. Over 50% of UK retailers were supplied by one wholesaler while the remainder were stocked by a mixture of one other wholesaler and/or direct imports from the source country. We estimate that up to 18,500 ornamental polychaetes (16,980 sabellids and 1,018 serpulids) are sold annually in the UK revealing a drastic underestimation of currently accepted trade figures. Incorrect identification (based on exporting region or visual characteristics) of traded animals exacerbates the inaccuracy in market quantification, although identification of preserved sabellids using published keys proved just as inconclusive with high within-species variability and the potential for new or cryptic species. A re-description of the polychaete groups traded using a combination of molecular and morphological techniques is necessary for effective identification and market quantification. This study provides the first assessment of ornamental polychaetes but more importantly highlights the issues surrounding the collection of baseline information necessary to manage the aquarium trade. We recommend that future management should be community based and site-specific with financial and educational support from NGOs, local governments and industry members.

We examined the bacterial accumulation and digestion in the alien polychaete Branchiomma bairdi. Microbiological analyses were performed on worm homogenates from "unstarved" and "starved" individuals and on seawater from the same sampling site (Ionian Sea, Italy). Densities of culturable heterotrophic bacteria (22. °C), total culturable bacteria (37. °C) and vibrios were measured on Marine Agar 2216, Plate Count Agar and TCBS Agar, respectively. Microbial pollution indicators were determined by the most probable number method. B. bairdi was able to accumulate all the six considered microbiological groups which, however, differ in their resistance to digestion. B. bairdi results more efficient than the other two co-occurring sabellids in removing bacteria suggesting that it may counteract the effects of microbial pollution playing a potential role for in situ bioremediation. Thus a potential risk, such as the invasion of an alien species, could be transformed into a benefit with high potential commercial gain and economic feasibility.

Within Annelida, the family Sabellidae is a particularly interesting clade in which to carry out comparative studies of regeneration, as its members vary in regeneration potential, with some even lacking this ability completely. However, data on the regenerative potential of sabellids are available only for a few species investigated early in the last century, and even for those, many aspects of regenerative ability are yet to be determined. In the present study, we compared the morphology of the regeneration process of anterior and posterior ends in Sabella spallanzanii and Branchiomma luctuosum, two sabellids that belong to closely related genera. Members of S. spallanzanii exhibited lower mortality in response to wounding and greater regenerative ability, with amputees able to complete the regeneration process more rapidly than in B. luctuosum. Moreover, results from this study suggest that adults of S. spallanzanii and B. luctuosum use different mechanisms to restore lost anterior body parts. In S. spallanzanii, both morphallaxis and epimorphosis appear to be important in anterior end regeneration, but in B. luctuosum, only epimorphosis appears to be important. Such variation among closely related taxa sharing similar body plans has rarely been reported, but might be profitably examined using molecular approaches in these and other species of sabellids. Results of such studies interpreted in the context of phylogeny may ultimately provide insight into the evolution of regeneration.

An unusual and abundant orbiniid polychaete, collected from the channel of an aquaculture facility in Brindisi (Adriatic Sea, Italy), has been identified as the subtropical-tropical American species, Naineris setosa (Verrill, 1900). The specimens have been redescribed with SEM used for the first time to illustrate their morphology. The taxonomy and ecology of the species is reviewed. The presence of dorsal crests on abdominal segments and heavily vascularized branchiae may be an adaptation to a low-oxygen habitat. The possible origin of the Brindisi worms is discussed together with the known ecology of N. setosa in American waters. Although it is unlikely that any of the specimens escaped from the aquaculture facility into the Adriatic Sea, the present account documents the occurrence of the worm, and the possibility it could be encountered elsewhere in the region.

The present work reports on recent biodiversity records of Mediterranean native species such as Olindias phosphorica in the Turkish Aegean Sea and extended distribution of eleven alien species in the Mediterranean. These are: Bursatella leachi (Mollusca, Gastropoda: Algeria); Callinectes sapidus (Crustacea, Decapoda: Greek Ionian Sea); Caprella scaura (Crustacea, Amphipoda: Mar Piccolo of Taranto); Fistularia commersonii (Fish: Saronikos Gulf, Aegean Sea); Sphoeroides pachygaster (Fish: South Turkey); Musculista perfragilis (Mollusca, Bivalvia: South Turkey); Sepioteuthis lessoniana (Mollusca, Cephalopoda: central eastern coast of Tunisia); Flabellina rubrolineata (Mollusca, opisthobranchia: central Aegean, Greece); Hesionura serrata (Polychaeta: Apulian coast); Stephanolepis diaspros (Fish: Saronikos Gulf, Aegean Sea); and Parvocalanus crassirostris (Crustacea, Copepoda: Lesvos Island, Greek Aegean Sea).

Thirty-eight nonindigenous marine species (NIS) (macroalgae, sponges, hydrozoans, molluscs, polychaetes, crustaceans, ascidiaceans and fish), are reported from the Apulian coast of Italy. Shipping, aquaculture and migration through the Suez Canal are the main pathways of introduction of the NIS. In Apulian waters, 21% of NIS are occasional, 18% are invasive and 61% are well-established. It is highly probable that more NIS will arrive from warm-water regions, because Mediterranean waters are warming. Furthermore, some of the successful NIS must have the ability to become dormant in order to survive adverse conditions, either seasonal or during long journeys in ballast waters. The identification of NIS depends greatly on the available taxonomic expertise; hence the paucity of taxonomists hinders our knowledge of NIS in our seas. We propose the creation and maintenance of a network of observatories across the Mediterranean to monitor the changes that take place along its coasts.

Nine nominal species are known from Antarctica and adjacent waters that have been assigned to the genus Perkinsiana (Polychaeta: Sabellidae). Taxonomic notes for these species are provided. Currently, only six species are considered valid: Perkinsiana antarctica (Kinberg), P. decorata (Rullier), P. borsibrunoi Giangrande and Gambi, P. magalhaensis (Kinberg), P. milae Giangrande and Gambi and P. pusilla (Johansson); P. antarctica (Gravier) is incertae sedis; P. littoralis (Hartman) is a suggested synonym of P. magalhaensis (Kinberg) and P. antarctica (Gravier), while Potamilla antarctica christenseni Augener probably belongs to the genus Notaulax. Perkinsiana is amended based on the presence of a palmate membrane and radiolar flanges, and three types of abdominal chaetae. The new species Perkinsiana brigittae sp. nov. is here described from collections taken by the U. S. Antarctic Research Program (USARP) at Wilkes Station. A taxonomic key for species of Perkinsiana from Antarctica is provided.

Due to the presence of the complex life cycles involving a benthic adult and a pelagic larval phase, the study of benthic community dynamics cannot ignore investigations of the processes occurring in the water column. Current investigations focus mainly on larval dispersal from an evolutionary and a biogeographic perspective, taking into account also population connectivity, conservation planning and coastal management. In the present paper we underline the need to improve knowledge of the main traits of marine invertebrate life cycles, highlighting the limits and challenges of current approaches. Firstly, we summarized the changing approaches within community studies, following the paradigm shifts found in recent marine ecological research, from supply-side ecology to connectivity, and involving the concepts of open and closed populations. Secondly, we analysed the main larval traits influencing dispersal, paying particular attention to pelagic larval duration in light of the few available data for connectivity studies. The difficulty in estimating many of the main traits of larval ecology make numerical simulation fundamental for a better understanding of the relationship between propagule dispersal and seawater dynamics, both being highly variable. We conclude that some essential biological information is still lacking for the proper integration of the modeling approaches. Thus it is necessary to further investigate the life-cycle traits and physiological and ecological characteristics of each species, an approach known as autecology or natural history. All too frequently modern ecologists ignore such reductionist approaches, although they are essential for a full understanding of processes, such as connectivity and metapopulation dynamics.

In order to utilize the biomass of the polychaete Sabella spallanzanii Gmelin as a dietary supplement for fish nourishment, we conducted some experiences of rearing this worm in the Mediterranean Sea. A preliminary study on the growth of this species on suspended plastic nets was conducted in two sites of the Apulian coast with different trophic features. Data for the first 12 months show that S. spallanzanii reared in eutrophic conditions grows producing a biomass higher than the natural population. The acquired experience was afterward tested in a pilot plant located in the Mar Piccolo of Taranto, a eutrophic area where polychaetes were co-cultured with Mytilus galloprovincialis within a long-line farm. The slight mortality recorded during the first 2 months and quite negligible after 4 months, the high increase in volume and biomass of the reared polychaetes, especially at high density (70 individuals for each net), demonstrated the advantage of rearing S. spallanzanii in the pilot plant with low cost of production and high profit. If the acquired technology is applied to a medium farm containing up to 400 sectors, the biomass produced indeed might reach about 1.36 tons/year. In conclusion, on the basis of our results, we demonstrated the possibility to obtain high-value worm biomass coupled to mussel biomass in a completely non-fed culturing system without increasing, but presumably reducing the environmental impact due to mussel farming.

Explaining the high variability of regenerative ability across metazoan taxa is one of the major challenges in modern biology. Although common and widespread, regeneration shows a heterogeneous distribution and most authors consider regeneration capacity to be an ancestral trait that has been restricted or completely lost over the course of metazoan evolution. Basal Metazoans show the highest capacity for regeneration. By contrast, this feature is highly variable within bilaterians, with many taxa limited in their capacity for regeneration or not regenerating at all. The causes of the loss and/or maintenance of regeneration remain poorly understood, with most explanations invoking adaptive mechanisms. In the present study Metazoan regeneration is discussed with reference to stem cell biology, tissue plasticity, evolution of tissue complexity, cell turnover and lifespan. The presence or absence of regenerative ability cannot be seen only as an adaptation to a particular environment but can also be a consequence of body plan and developmental constraints such as may arise from the evolution of an adaptive immune system.

Collection of live invertebrates from coral reefs has increased dramatically over the past two decades in response to the growing marine aquarium industry, and currently, more than 500 species (excluding corals) are traded globally. Aquaculture of ornamental species is deemed a priority solution in mitigating the effects of wild collection but expanding the range of species is limited by bottlenecks at key life history stages. A novel culture method for ornamental sabellids, which utilises their outstanding regenerative capacity in a process similar to coral ‘fragging’, has been developed and survivorship after regenerative development assessed. Sabella pavonina, a temperate species found around the UK, was used as a model to develop a culture technique which was subsequently transferred to a tropical species of Sabellastarte. Survivorship of S. pavonina was high (≥80%) in individuals which had been cut into as many as eight fragments and all fragments completed regenerative development within a four week period. Sabellastarte species exhibited ≥75% survivorship when cut into just two fragments, but higher mortality was recorded with increasing number of cuts, with only 20% of fragments from individuals cut into eighths surviving the duration of the experiment. Both test species were capable of regenerating cephalically and caudally within a four week period. Caudal regeneration involved the healing of the cut surface, reconstruction of the pygidium and subsequent segment addition, while cephalic regeneration was a more complex process of wound healing, reconstruction of a new mouth and the development of the branchial crown structure. It is concluded that differences in survivorship between S. pavonina and Sabellastarte sp. could be attributed to either infection due to sub-optimal water quality in the test tanks, or species-specific differences in the area of wound size in relation to the length of the fragment. Optimisation of survivorship and the speed of regenerative growth could be improved with the enhancement of the culture system.

The reproductive biology and population ecology of the sabellid polychaete, Sabella pavonina (Savigny) inhabiting an intertidal sand bank in Langstone Harbour, Portsmouth, was investigated between February 2007 and June 2009. 'Blind' thrown quadrats and sediment cores were used to characterise population distribution patterns at the site, and monthly coelomic fluid samples from 30 individuals were used to investigate the reproductive biology of the population, sex of the specimen, the presence of coelomocytes and the development of oocytes. Highest population densities (30.58 m(-1) +/- 8.05) were recorded on the low shore (0.4 m above chart datum) where the largest size particle fractions and lowest percentage organic content were found. Poisson distribution analysis showed the population was 'clumped' at the shore level, with a maximum number of 188 individuals in a 0.25 m(2) quadrat, and within individual quadrats with up to 23 individuals in a 100 cm(2) subsection. Sabella pavonina has an annual reproductive cycle which culminates in May/June spawning period. Oogenesis was a long process, first observed by the presence of small eggs (20 mu m) from September onwards and maximum oocyte diameters were recorded (270 mu m) between May and June prior to spawning. Between- and within-individual synchronicity was greatest in the early stages of oogenesis (October to February) when oocyte diameters ranged from 50-100 mu m; however, increasing oocyte diameters were observed from March when rapid growth was initiated. Day length and sea temperature are candidates for exogenous cues controlling gametogenesis and possible mechanisms concerning fertilization in the species are discussed.

The polychaete Myxicola infundibulum (Renier) produces a large amount of dense mucus which forms a gelatinous envelope where the worm lives. In the present study we evaluated some of the physical-chemical properties of this matrix such as viscosity, osmolarity, electrical conductivity, and protein, carbohydrate and total lipid content The presence of an antibacterial lysozyme-like activity as well as the density of culturable bacteria at 22 degrees C and vibrios and associated macrofauna were also investigated. The water content of M. infundibulum mucus was 95 +/- 0.5%. By dry weight, 38 +/- 1.2% was protein, 2 +/- 021% was carbohydrate and only 3% was lipid. Most of the remainder of the dry weight (about 57%) was inorganic. The mucus of M. infundibulum exerted a lysozyme-like activity evidenced on Petri dishes inoculated with Micrococcus luteus cell walls with a diameter of lysis of 8.4 +/- 0.3 mm, corresponding to 1.15 mg ml(-1) of hen egg white lysozyme. Notwithstanding this high antibacterial activity, the mucous tubes of M. infundibulum contained a high density of culturable heterotrophic bacteria at 22 degrees C, of which presumptive culturable vibrios accounted for 4.6 +/- 0.2 x 10(3) CPU ml(-1). Moreover, tubes were found to be colonized by several specimens of the polychaete Lumbrineris cfr. latreilli. Therefore the mucus of M. infundibutum appears to provide defence against some bacteria and food supply for the growth of others, that in turn could be utilized by macrofaunal organisms. On account of these features this matrix represents an accessible and renewable resource that could repay further exploration from several points of view.

In the present paper, morphological and ecological observations on 4 sabellid taxa, Branchiomma bairdi, B. luctuosum, Megalomma lanigera and Myxicola sp., collected from the coastal lake of Faro (Messina, Ionian Sea) (26-36 psu), are reported. Megalomma lanigera, Myxicola sp. and B. luctuosum were collected from the soft bottom in shallow water and B. bairdi from the hard bottom of an internal channel. The presence of the latter is remarkable, as there is no previous record of this species along the Italian coast, and it confirms the lake of Faro as a very favourable environment for the introduction of alien species, which has occurred frequently as a result of aquaculture. High intraspecific variation was observed for M. lanigera, whilst more extensive analysis is required to ascertain the taxonomic status of the Myxicola specimens, including a review of all Mediterranean data currently attributed to M. infundibulum.

Bio-constructions by Sabellaria worms play a key functional role in the coastal ecosystems being an engineer organism and for this reason are the object of protection. The most widespread reef building species along Atlantic and Mediterranean coasts is S. alveolata (L.), while the aggregations of S. spinulosa are typically limited to the North Sea coasts. This paper constitutes the first detailed description of unusual large S. spinulosa reefs in the Mediterranean Sea. Defining current health status and evaluating the most important threats and impacts is essential to address conservation needs and design management plans for these large biogenic structures. Present knowledge on Mediterranean reefs of S. alveolata is fragmentary compared to Northeast Atlantic reefs, and concerning S. spinulosa, this paper represents a focal point in the knowledge on Mediterranean reefs of this species. A one-year study on temporal changes in reef structure and associated fauna is reported. The annual cycle of S. spinulosa reef shows a spawning event in winter-early spring, a period of growth and tubes aggregation from springearly summer to autumn and a degeneration phase in winter. The variations exhibited in density of the worm aggregation and the changes in the reef elevation highlight a decline and regeneration of the structure over a year. The many ecological roles of the S. spinulosa reef were mainly in providing a diversity of microhabitats hosting hard and sandy bottom species, sheltering rare species, and producing biogenic structures able to provide coastal protection. The Mediterranean S. spinulosa reef does not shelter a distinctive associated fauna; however the richness in species composition underscores the importance of the reef as a biodiversity hot-spot. Finally, the roles of the biogenic formations and their important biotic and physical dynamics support the adoption of strategies for conservation of Mediterranean S.spinulosa reefs, according to the aims of the Habitat Directive.

Sabellidae is the second most diverse polychaete family in the Adriatic Sea, after Syllidae. Herein we report the updated list of the Sabellidae and Fabriciidae families in the Adriatic Sea deriving both from literature data and presently conducted researches in the northern Adriatic. During these researches polychaetes were sampled from three offshore soft-bottom and three coastal rocky shore stations. Among the analysed material three Sabellidae species are new records for the Adriatic fauna, while four Sabellidae and one Fabriciidae species were recorded for the first time in the northern part. Two new species were found and described: Amphicorina rovignensis spec. nov. and Megalomma pseudogesae spec. nov. These findings increase the number of Sabellidae taxa recorded in the northern Adriatic from 29 to 38. Our results point out the lack of the recent taxonomic studies in the area, but might also indicate the widening of the species areal. Taking into consideration that studies on only six stations raised the number of known sabellid taxa from the area by 31%, our results support the need for the regular taxonomic updating of the polychaete fauna in the northern Adriatic. © Marine Biological Association of the United Kingdom 2013.

We report results from a 2-year study on the succession pattern of macrofouling assemblages in the Taranto Sea, an important alien species hotspot in the Mediterranean Sea. Four sets of PVC panels were used as macrofouling collectors; each unit was installed at a different time (April 2013, July 2013, October 2013 and January 2014) and then surveyed quarterly for 1 year. The macrofouling community consisted of 93 sessile invertebrate species, of which 16 were NIS and five were cryptogenic. In both years non-indigenous species (NIS) recruitment occurred mainly in the quarter July/October in concert with the settlement of pioneer autochthonous species. This recruitment is independent of immersion time, occurring on both bare substrates and on previously colonized panels. This increase in NIS coverage is influenced by the development stage of the community, suggesting that NIS grow better without potential competitors. Two sets of NIS were distinguished. The first included abundant ascidians, serpulids, and bryozoans that are structuring components of early communities when favorable conditions exist (i.e. a lack of competitive autochthonous species). After settlement, these species are unable to develop in laterstage communities. The second set of NIS was composed of sabellid worms that settle in early and late communities but, unlike the other NIS, are able to persist and become dominant in late macrofouling communities independent of seasonal changes.

Since the first discovery along the Italian coasts in 2004 of the polychaete Branchiomma bairdi, it has spread very quickly, reaching some localities in very high densities. In order to monitor its colonization, recruitment was investigated by means of PVC panels immersed in the Mar Grande of Taranto (Ionian Sea). Panels were monitored every three months from April 2013 to January 2015. The species showed the ability to settle on bare panels as well as on panels with a developed fouling community. Two years of monitoring identified two different cohorts, with recruits appearing in both years on panels submersed from July to October. Based on these observations B. bairdi is a short-lived species (no more than one year), reproducing at a temperature ranging from 20 to 29°C and reaching sexual maturity three months after recruitment. Oocytes were found in the coelom only in the warmest months and oogenesis was not synchronous either within each individual or within the population. Total annual secondary production was estimated at 43.42 g m−2 year−1. Annual mean biomass was 20.03 g m−2. The corresponding P/B ratio was 2.1678. This study may explain the invasiveness of B. bairdi; indeed, a rapid generation turnover coupled with a short lifespan, rapid growth and early maturity are common traits in most invasive species.

Sabella spallanzanii is a large tubicolous filter feeder polychaete common in the Mediterranean fouling assemblages, where it plays an important role in structuring the community. Its reproductive biology is well known and had has been investigated since 1993. During the past few years, a shift in its reproductive period has been observed. In 2008 the presence of ripe eggs in the females was observed at least two months in advance compared to the past. This was confirmed during the 2009 when spawning and fertilization were observed three months in advance compared to the past. Possible causes of this shift may be related to the increasing surface temperature in the Central Mediterranean Sea.

Phylogeny of Syllidae is under debate due to new studies based on molecular and morphological data. The noticeable taxonomic diversity of syllids (about 700 listed species) is also mirrored in the array of reproductive strategies as well as in sperm morphology, counting a display of forms already supposed to reflect phylogenetic relationships between the species. The sperm ultrastructure of Syllis gerlachi, S. prolifera and S. vittata is herein presented and compared to the Syllinae species studied previously. Moreover, the egg structure and the gamete allocation within stolons of S. vittata are particularly investigated. Both male germinal cells at different level of maturation and oocytes were found in the same individual of S. vittata, suggesting simultaneous hermaphroditism. The ultrastructural analysis revealed that the observed spermatozoa belong to the ect-aquasperm type resembling those of the similar studied species (Syllis sp., S. pigmentata and S. krohni). Differences in the acrosome structure and nucleus shape are in accordance with a recent phylogenetic reconstruction and suggest a trend in the evolution of spermatozoa in Syllinae toward the development of the apical part. However, further molecular and ultrastructural analyses are needed to support this hypothesis. This is the first record of simultaneous hermaphroditism within Syllinae

The new species Echinofabricia rousei is described for the Mediterranean Sea based on specimens collected along the Sardinia Coast (Porto Conte). The genus Echinofabricia is reported for the first time in the Mediterranean area. At present three species are described within the genus: E. goodhartzorum, described from the Caribbean, E. dubia, described from the East Pacific (Hawaii) and E. alata from Australia.

The Genus Nereis L., 1758 (Polychaeta, Nereididae): State of the Art for Identification of Mediterranean Species. The existence of critical problems in the identification of species within the genus Nereis L., 1758 (Annelida Polychaeta: Nereididae) has led to several misidentifications within Mediterranean taxa. In the present paper we report a discussion on the Mediterranean species, with a re-examination of specimens collected along the Italian coasts. A redescription of each species is provided, pinpointing the diagnostic characters with detailed figures for easy identification. Old and recent synonymies are also discussed and a key for identification is provided.

Two new species, Megalomma longoventralis sp. nov. and M. adriaticum sp. nov., are described based on material collected along the Italian and Croatian coasts. The finding increased the number of species up to now recorded for Mediterranean and Italian coasts, indicating that the Megalomma genus is represented in the Mediterranean area by six taxa, living in a range of habitats and depths: M. lanigera, M. cfr. claparedei, M. messapicum, M. pseudogesae, M. longoventralis and M. adriaticum. Some features of the genus Megalomma are revised, and a dichotomous key for Mediterranean species is provided to facilitate their identification. http://zoobank.org/urn:lsid:zoobank.org:pub:822E64C0-3925-4EC6-91A7-0233BCD3B3DF © 2015 Unione Zoologica Italiana

We investigated the bacterial accumulation and digestion capability of Polyandrocarpa zorritensis, a nonindigenous colonial ascidian originally described in Peru and later found in the Mediterranean. Microbiological analyses were carried out on homogenates from “unstarved” and “starved” ascidians and seawater from the same sampling site (Adriatic Sea, Italy). Culturable heterotrophic bacteria (22 °C), total culturable bacteria (37 °C) and vibrios abundances were determined on Marine Agar 2216, Plate Count Agar and TCBS Agar, respectively. Microbial pollution indicators weremeasured by themost probable number method. All the examinedmicrobiological groups were accumulated by ascidians but differently digested. An interesting outcome is the capability of P. zorritensis to digest allochthonous microorganisms such as coliforms as well as culturable bacteria at 37 °C, counteracting the effects of microbial pollution. Thus, the potential exploitation of these filter feeders to restore polluted seawater should be taken into consideration in themanagement of this alien species.

Taxonomic Sufficiency (TS) has been proposed as a short-cut method to quantify changes of biological assemblages in environmental monitoring. However, issues about the efficacy of taxonomic surrogates in depicting long-term temporal patterns of marine assemblages are still scant. Here we report on the adoption of TS combined with data transformations to describe patterns of North Adriatic polychaete assemblages through 20 years. Univariate and multivariate analyses revealed large spatialetemporal variation charactering the assemblages. The efficiency to discriminate between the two research periods (1990e1994 vs. 2004e2008) was reduced when data were analyzed at family and order level leading to misinterpreting the sources of assemblage variation. Further information was lost with data transforms. Families may represent appropriate assemblages’ descriptors in long-term monitoring, but using TS coupled with data transformations could lead to hazardous loss of information. We suggest that periodical analysis at fine taxonomic level should be routinely alternated to long-term monitoring based on TS in order to check its effectiveness

During several surveys conducted along the Ionian coast of Italy, specimens belonging to two species of the genera Monticellina and Protocirrineris were collected and described as new species in the present study. Protocirrineris purgamentorum sp. nov., collected from hard bottom near a sewage outfall, is mainly characterized by having branchiae commencing from the anteriormost tentacle-bearing chaetiger. Monticellina marypetersenae sp. nov., found in muddy sediments of the Gulf of Taranto, is unique among its congeners by having the first pair of branchiae arising anteriorly from the dorsal tentacles, notopodia with only capillaries, and four peristomial rings.

Sabella pavonina Savigny, 1920 is a species common to sheltered areas of northwest Europe and reported also in several Mediterranean sites. However, most Mediterranean records refer to faunistic lists with only few papers reporting morphological descriptions supported by drawings or photographs, most of which are short and out-dated. Moreover, no analysis of intraspecific variations among Mediterranean populations is available. In the present paper we provide the descriptions of individuals identified as S. pavonina belonging to four different Mediterranean populations and deposited at the Laboratory of Zoology of the Salento University. We analyzed the species morphological variation within the Mediterranean area compared to the deposited neotype and some other specimens collected from the type locality (Plymouth) and from Portsmouth (English Channel). The examined specimens from the four Mediterranean localities all differ from the English Channel Plymouth specimens with respect to a higher crown/body length ratio and smaller body size. Among them, individuals from Taranto and Gela resemble the morphology of the neotype specimens from Plymouth more closely than the others, with only a few differences, mostly involving the branchial crown features. Statistical analysis shows the occurrence of two different groups, one formed by specimens collected in sites located at deeper depths (100–130 m), separated by another containing specimens collected at shallower depths (5–10 m). Based on these considerations, it could be hypothesized that the specimens collected from greater depths do not actually belong to the S. pavonina species. However, the poor condition of the material does not yet allow the establishment of a new taxon. Only the examination of additional material coupled with further data including genetic analysis, will clarify the status of the taxon S. pavonina within the Mediterranean area.

In order to investigate the intensity and variability of fouling recruitment on artificial hard substrates, three sites were chosen in the First Inlet of the Mar Piccolo of Taranto (Southern Italy, Ionian Sea). Taxa richness and percentage coverage were examined in three different sampling times within each site. Differences were tested both by univariate and multivariate statistical analysis (ANOVA, SIMPER and MDS). The results show that each site seems to be characterized by its own structural make-up over the whole period of observation, underlying the presence of large-scale variability. By contrast, variability on a smaller scale within each site (replicates) appeared less marked, both in space and time. A set fa quite stable group of species characterized each site. Differences between sites were maintained over time with a difference in community evolution although with a tendency towards a higher similarity in species composition along the time.

Sabellaria alcocki Gravier, 1906, described for the Indian Ocean, should not be present in the Mediterranean area. Though S. spinulosa alcocki, a Mediterranean variety, can be well-distinguished from S. alcocki, it has recently been referred to as S. alcocki. Thus, S. alcocki appears in the Italian coast checklist. The recent finding of S. spinulosa reefs along the southern Adriatic coast, the first report of these biogenic constructions in the Mediterranean area, allowed us to compare its morphological variability with that of S. alcocki. A morphometric analysis of the opercular paleae showed a great deal of intrapopulation, size-independent variation, which cannot justify the existence of varieties within S. spinulosa. Moreover, the analysis of post-settlement development showed that opercular features change during individual growth. Recently settled individuals resemble S. alcocki, while the more advanced life stages become closer to S. spinulosa. Accordingly, we hypothesize that part of the erroneous Mediterranean records of S. alcocki could correspond to specimens of S. spinulosa at different stages of development.