Mytilus Galloprovincialis Lamarck Research Articles

Stable isotopic composition of tissues and shells in the Mediterranean mussel, Mytilus galloprovincialis, in estuarine and aquaculture settings

The Mediterranean mussel, Mytilus galloprovincialis Lamarck, 1819 is a widely distributed commercially important bivalve species, and is one of two cultivated bivalve species in the Adriatic Sea, with the Krka River estuary being a key aquaculture location. Understating the feeding ecology of M. galloprovincialis could help aquaculture be more efficient. The aim of this study is to use stable isotopes to advance our understanding of M. galloprovincialis feeding ecology, as well as explore the potential of their shell as proxies for environmental change. We analyzed stable isotope composition (hereafter, δ13C and δ15N), of M. galloprovincialis soft tissue, as well as the δ15N signature of its shell, over one year at multiple sites in the Krka River estuary. Mussels showed differences in the isotopic niche depending on the site, indicating that feeding varies according to geographic location, likely due to specific conditions in the Krka River estuary and differences in food availability. During our entire survey period, marine organic carbon was the dominant source in the mussels cultivated in the Krka estuary. However, in the period from late summer to late autumn, the contribution of freshwater carbon sources increased for both sites situated in the middle estuary. The distinct feeding patterns observed at each sampling site could be attributed to a combination of factors such as local hydrographic conditions, food availability, and the presence of other competing species. Overall, the stable isotope results present valuable information on the feeding ecology of Mytilus galloprovincialis, highlighting the complex interactions between environmental factors and feeding habits. The results of our study contribute to the isotope data archive for M. galloprovincialis. Furthermore, this work shows the potential of M. galloprovincialis shell δ15N values as an indicator for nitrogen loading in aquaculture settings and coastal marine environments.

Evaluation of the health of Mediterranean mussels (Mytilus galloprovincialis Lamarck, 1819) distributed in the Çanakkale strait, Turkey

The observation of mortality in Mediterranean mussels (Mytilus galloprovincialis) distributed in the Çanakkale Strait in recent years was influential in developing the research question for this study. In this study, the presence of bacteria (Vibrio spp.) and parasites (Marteilia spp. and Haplosporidium spp.) in mussels collected from Kumkale, Kepez, and Umurbey stations in the Çanakkale Strait was investigated seasonally. Microbiological findings, histopathology, oxidative stress enzymes and their gene expressions, lipid peroxidation, lysosomal membrane stability, and changes in haemolymph were examined. In summer samples, both the defence system and the extent of damage were higher in gill tissue. In winter samples, enzyme activities and lipid peroxidation were found to be predominantly higher in digestive gland tissues. Histological examinations and Hemacolor staining revealed the presence of protozoan cysts, and for bacterial examination, molecular analysis performed after culturing revealed the presence of 7 Vibrio species. While the total numbers of heterotrophic bacteria detected in all samples were at acceptable levels, the predominance of Vibrio spp. numbers among the total heterotrophic bacteria detected in almost all samples were noteworthy. The total hemocyte count was calculated as 5.810(4)±0.58 (cells/mm3) in winter and 7.210(4)±1.03 (cells/mm3) in summer. These factors are considered to be possible causes of mussel mortality.

A Comparative Assessment of Content of a Number of Heavy Metals in Soft Tissues of Mytilus trossulus A. Gould, 1850, Mytilus galloprovincialis Lamarck, 1819 (Bivalvia, Mytilidae) and their Hybrid Forms from Minonosok Bay of Peter the Great Bay (Sea of Japan)

A Comparative Assessment of Content of a Number of Heavy Metals in Soft Tissues of Mytilus trossulus A. Gould, 1850, Mytilus galloprovincialis Lamarck, 1819 (Bivalvia, Mytilidae) and their Hybrid Forms from Minonosok Bay of Peter the Great Bay (Sea of Japan)

Fan mussel Pinna nobilis Linneaus, 1758 spat collection on ''Christmas tree'' rope in the Mali Ston Bay area (South Adriatic Sea)

During November 2006 on a 500 m long experimentally placed ''Christmas tree'' rope collector for juvenile mussels (Mytilus galloprovincialis Lamarck, 1819) placed the previous year a significant number of juvenile fan mussels (Pina nobilis Linnaeus, 1758) were observed. Live juvenile individuals (N=322) of P. nobilis with shell length from 17 to 93 mm were found in two sampling events. All juvenile fan mussels were found exclusively on deeper parts of the mussel rope. Observed population density was from 6 to 43 individuals per meter of the rope collector. The 120 smallest juveniles of P. nobilis were separated for the purpose of monitoring the growth rate in suspension, and the remaining juveniles were placed in the natural environment.

Seasonal growth and allometric indices of the mussel Mytilus galloprovincialis Lamarck, 1819, from the coastal zone of the Black Sea in relation to environment quality, mollusc sex and shell coloration

For the first time, experimental data on the seasonal shell growth rate and its allometric indices H/L (ratio of height to length), D/L (ratio of width to length) of M. galloprovincialis are presented in relation to environment quality, mussel sex, size and shell coloration. In this field experiment mussels of two size groups with the shell lengths of 35 and 60 mm were selected. Mussels of both sizes were placed in cages and deployed in a conditionally clean water area of mussel-and-oyster farm and in a harbour under anthropogenic impact. The length (L), height (H) and width (D), of the mussel shells were measured every season. In the 35-mm group, it was noted that in the post-spawning winter period males grew faster than females and the growth rate of mussels with the black shell coloration was higher than that of mussels with brown shells. For mussels of both sexes with the shell length of 35 mm from the conditionally clean water area, the growth rate was three times as high as for males and females from the polluted area; in the 60-mm group, it was twice as high. Mussels with the shell length of 35 mm were more sensitive to unfavorable conditions, which fact renders them more efficient in environmental monitoring. The most indicative was the H/L index, which can be adopted as a water area pollution index. Environment quality (including pollution, food availability and hydrodynamic conditions) of the compared water areas had a significant impact on the shell length growth and allometric indices of mussels.

Lysosomal Membrane Stability of Mussel (Mytilus galloprovincialis Lamarck, 1819) as a Biomarker of Cellular Stress for Environmental Contamination.

The lysosomal membrane stability (LMS) of hemocytes in wild mussels (Mytilus galloprovincialis) as a biomarker of cellular stress for chemical pollution was tested by neutral red retention time (NRRT) assays. To assess the environmental contamination in the study area, seawater quality and pollutant bioaccumulation throughout the soft tissue of mussels were investigated. The samples were collected in July 2022 at four sites on the Romanian Black Sea coast considered to be differently affected by contamination. To support the suitability of LMS as a biomarker of contaminant-induced stress, the contaminant body burdens of the mussels were compared with the NRRT values. The results showed a significantly reduced NRRT in all investigated locations, particularly in port areas (mean retention time between 11 and 14 min). The elevated bioaccumulation of organochlorinated pesticides (OCPs) and polychlorinated biphenyls (PCBs) and low NRRTs were observed at the most contaminated sites (i.e., ports). The low lysosomal stability reflected stress and damage in the hemocytes of mussels and could be related to the body burdens of contaminants. LMS is an effective indicator of health status in mussels and could be considered a sensitive biomarker of cellular stress induced by contaminant exposure.

An Assessment of the Cultivation Potential and Suitability for Human Consumption of Mediterranean Mussels (Mytilus galloprovincialis Lamarck, 1819) from the Yalova Coast of the Marmara Sea

This study aimed to determine into potential suitability of juvenile Mediterranean mussel (Mytilus galloprovincialis) for cultivation and human consumption collected from various stations (Kapaklı, Çınarcık, Koru, and Deveboynu) along the Yalova coast of the South Marmara Sea during the spring season. Specifically, meat yield, condition index, moisture content, density of fouling organisms on the shells, and heavy metal concentrations (copper, zinc, mercury, cadmium, lead, and arsenic) were analysed. The average meat yields for Çınarcık, Deveboynu, Kapaklı, and Koru were found to be 24.51±2.96, 21.72±3.92, 23.75±2.31, and 21.54±4.01, respectively. Similarly, the average condition index were found to be 7.29±1.16, 6.02±0.97, 7.30±0.77, and 5.94±1.39 for Çınarcık, Deveboynu, Kapaklı, and Koru, respectively. The average shell component index for Çınarcık, Deveboynu, Kapaklı, and Koru were detected that 72.06±2.75, 74.39±4.13, 69.99±2.55, and 74.68±4.54, respectively. Additionally, the average moisture contents were found to be 82.63±1.95, 83.34±3.23, 84.02±1.82, and 83.40±4.17 for Çınarcık, Deveboynu, Kapaklı, and Koru, respectively. The statistical analysis revealed significant differences (p<0.05) in these parameters among the stations. Moreover, the quantities of competitive and fouling organisms, such as polychaetes and barnacles, were found to be highest in the Deveboynu and Koru stations. It has been determined that copper, zinc, mercury, and lead levels of the mussels are suitable for human consumption in all stations. However, arsenic values exceeded legal limits in Çınarcık, Koru, and Deveboynu, and cadmium values exceeded legal limits in all stations.

Adenylate System State, Malate Dehydrogenase Activity and Expression Level in Tissues of Mytilus galloprovincialis Lamarck, 1819

Adenylate System State, Malate Dehydrogenase Activity and Expression Level in Tissues of Mytilus galloprovincialis Lamarck, 1819

Growth Performance of Mytilus galloprovincialis Lamarck, 1819 under an Innovative Integrated Multi-Trophic Aquaculture System (IMTA) in the Mar Grande of Taranto (Mediterranean Sea, Italy)

The cultivation of the Mediterranean mussel, Mytilus galloprovincialis Lamarck, 1819, has been tested in an innovative Integrated Multitrophic Aquaculture system (IMTA) in the Mar Grande of Taranto, as part of the EU-funded Remedialife project. This farming method could solve several problems including the low growth rate in mesotrophic environments while reducing the environmental impact of fish mariculture. Three productive cycles have been carried out. The first (2018–2019, traditional experiment) was conducted in three long lines around six cages of the fish farm in order to evaluate total mussel production under the innovative IMTA system and quality for human consumption by analyzing the concentration of culturable heterotrophic bacteria, total and fecal coliforms, Escherichia coli and Salmonella spp. in mussel tissues. In addition, 17 polycyclic aromatic hydrocarbons (PAHs), including 16 EPA priority compounds and seven polychlorinated biphenyls (PCBs), which are indicators of PCB contamination in the environment, were analyzed using gas chromatography in conjunction with a mass spectrometer. The second cycle (2020–2021, horizontal distance experiment) aimed to test the influence of fish cages on mussel growth by placing mussels near and far from the fish cages. The third cycle (2021–2022, vertical distance experiment) aimed to overcome the phenomenon of “heat waves” that can occur in the Mar Grande of Taranto during summer by testing the growth performance of mussels at two different depths (1 and 12 m). The following parameters were measured: Shell Length, L (mm); Shell Dry Weight, SDW (g); Flesh Dry Weight, FDW (g); Condition Index, IC = FDW/SDW. The results showed that the best growth performance was obtained near the fish cages and at a depth of 12 m. Moreover, the indicators of microbial contamination and concentrations of chemical compounds analyzed in mussel tissues cultured under the innovative IMTA system were in compliance with the reference values of European regulations.

Epibiotic association of encrusting cheilostome bryozoans on shells of an invasive mussel from rocky shores of South Africa, with the description of a new aviculiferous species of Chaperia

Rocky shores typically exhibit a variety of sedentary and free-moving forms of epibionts associated with the shells of mussel basibionts. This paper provides a first report on epibiotic bryozoans found on shells of the invasive Mediterranean mussel, Mytilus galloprovincialis Lamarck. More than 2500 mussels were collected between December 2019 and October 2020 from rocky shores during low spring tides across the south-southeast coast of South Africa. Ten percent of these mussels hosted epibiotic bryozoans. We examined a subset of these epibiotised mussels to assess the diversity of bryozoans. Three encrusting cheilostome species were identified: Chaperia atypica n. sp., Celleporella hyalina (Linnaeus), and Hippomonavella sp. This new species is the first Chaperia with avicularia and the first South African species with ooecia. This study highlights the biological diversity of epibiotic bryozoans on mussel shells and, given their differences in microtopography, the possibility that invasive species can provide a new substratum for rare, overlooked or undescribed species of epibionts.

Feeding intensity and daily mussel consumption of Rapa whelk (Rapana venosa) in the north-western Black Sea

Based on an experiment carried out in the north-western Black Sea (Snake Island), the feeding behavior of the Rapa whelk (Rapana venosa Valenciennes, 1846) was analyzed in relation to its size (N = 58; shell height: 30–90 mm). Mediterranean mussels (Mytilus galloprovincialis Lamarck, 1819) were placed in experimental cages with R. venosa to be used as food. It was found that the size of the prey was determined by the size of the predator. The mussels with a shell length of 20−40 mm were most affected by R. venosa. It was determined that the predator’s contribution to the deposition of mussel shells in the bottom sediments is also associated with its size. Feeding intensity varies from 41 mg to 99 mg of the total mass of mussels per 1 g of the total mass of R. venosa per day, depending on the size of the predator. The daily consumption of mussel soft tissue varied from 0.189 g ind.−1 per day−1 in small R. venosa specimens to 0.917 g ind.−1 per day−1 in large predators. Regression equations were obtained between the length and mass of the mussels consumed (total mass, soft tissue mass and shell mass) and the shell height of the predator.

Determination of the antimicrobial activity of lactic acid bacteria isolated from the Black sea mussel Mytilus galloprovincialis Lamarck, 1819

The present study reports on the determination of the antimicrobial activity of lactic acid bacteria (LAB) isolated from the Black sea mussel Mytilus galloprovincialis Lamarck, 1819. The samples were collected in the period of August 2018 until March 2021. The BIOLOG system was used for microbiological determination. From the mussel M. galloprovincialis Lam. four species of LAB were isolated - Sporolactobacillus kofuensis, Lactobacillus sakei, Streptococcus gallolyticus ss gallolyticus and Lactibacillus brevis. The activity of the strains was determined against test cultures (Escherichia coli 3398, Staphylococus aureus 745, Bacillus subtilis 6633, Salmonella typhimurium 3591, Listeria monocytogens 863 Enterobacter aerogenes 3691, Aspergillus niger, Penicillium claviforme, Saccharomyces cerevisae, Candida albicans 8673 and Candida glabrata 72). Before the analysis for antimicrobial activity, the LAB were cultured in media with different concentrations of sugars - 2, 5 and 10%. The results showed that 4 strains S. kofuensis, L. sakei, S. gallolyticus ss gallolyticus and L. brevis cultured on glucose and oligosaccharides completely lost their activity in all studied variants. Therefore, some carbohydrates (glucose) and oligosaccharides induce the synthesis outside the cell of biologically active molecules, which can probably be attributed to peptides/proteins.

Molecular genetic differentiation of native populations of Mediterranean blue mussels, Mytilus galloprovincialis Lamarck, 1819, and the relationship with environmental variables

Blue mussels of the genus Mytilus are important ecosystem engineers in intertidal and subtidal communities. The distribution of Mytilus mussels is influenced by a number of benthic and pelagic environmental variables (e.g., substratum type and availability, water movement, phytoplankton production, physical disturbance) as well as interactions between these variables. Because of its broad tolerance of environmental variation the Mediterranean species, Mytilus galloprovincialis, has the greatest ability of all blue mussels to colonise new geographic regions. Understanding how population genetic variation is related to, or caused by, environmental variation is important but has long been a challenge. The present study examined the genetic differentiation of native populations of M. galloprovincialis throughout its entire geographic range in the Mediterranean Sea, the Black Sea and the Sea of Azov using 53 single nucleotide polymorphisms (SNP loci). Mussels, in total 1004 individuals collected from 36 locations, were genotyped and combined with existing SNP data for mussels from 11 reference sites. Pairwise comparisons of F ST values, correspondence analysis (CA) and STRUCTURE analysis all revealed four groups of populations: the Atlantic Ocean; the western Mediterranean; the Aegean Sea; and the Azov, Black and Marmara Seas. One population – from Algeria (Oran West) – was intermediate between the two main groups of the Mediterranean Sea and Atlantic Ocean. Seascape genetic analyses using GLM and DistLM analyses were employed to test site-specific genetic variation as a function of 13 environmental variables. The GLM identified five environmental variables that explained variation in site-specific F ST values, whilst in the DistLM best-fit model only four were significant. These analyses suggest that a complex mix of environmental variables contribute to explaining genetic variation of M. galloprovincialis populations within the Mediterranean Sea, which most likely reflects the complex geological history of formation, isolation and reconnection among the regional sub-basins of the Sea.

Мікроскопічні водорості водойм Кінбурнської піщаної коси (НПП «Білобережжя Святослава», Україна)

Taxonomical composition of microscopic algae of different reservoirs (Dnieper estuary, Kefalny, Guryansky and Cherepashy lakes, Yagorlytsky Bay) of the Kinburn sand spit of north-western part of the Black Sea (National Nature Park “Biloberezhzha of Svyatoslav”) is studied. Material tests that is collected on sandy and silty soils served as for researches, and also in becoming overgrown with of mussels Mytilus galloprovincialis Lamarck, Mya arenaria L., Cerastoderma lamarcki Reeve and Balanus improvisus Darwin, macroscopic algae (Ceramium virgatum Roth, Cladophora vagabunda (L.) Hoek, C. siwaschensis C.Meyer, Ulva intestinalis L., Polysiphonia elongata (Huds.) Harv.) of Kіnburnska braid from September in 2019 for October in 2021. On the whole it was collected and analysed 90 standards. 116 species of microscopic algae are educed, that to 74 genera, 52 families, 31 orders, 9 classes, 6 divisions, belong, 3 kingdoms and 2 empires. After systematic composition Bacillariophyta (76 species) prevailed above Cyanophyta (26), Chlorophyta (7), Dinophyta (3), Chrysophyta (3) and by Haptophyta (1). 86 species of algae were found in the microphytobenthos of Yagorlyk Bay, 56 in Dnieper estuary, 33 in Cherepashy, 22 in Guryansky and 17 in Kefalny lakes. As a result of researches it was educed 2 new and 4 rare species of microscopic algae for the aquatorium of the Black Sea.

Determination of phytoplankton in water samples, algal biotoxins, microbiological parameters and microplastics in Mediterranean mussels (Mytilus galloprovincialis Lamarck, 1819) from an experimental pilot farm in the Calich Lagoon (Sardinia, Italy).

The aims of this paper were to collect and analyse preliminary data of phytoplankton in the water, biotoxins, Escherichia coli, Salmonella spp., Vibrio spp. and microplastic eventually present in farmed mussels, and to acquire information about the production capability from an experimental pilot farm of the Calich Lagoon. Two sampling sessions were carried out, in February and in May 2019, also monitoring the water condition (pH, temperature, salinity, dissolved oxygen, chlorophyll a). No potentially toxic algae were detected, and moreover no biotoxins (Paralytic Shellfish Poison, Diarrheic Shellfish Poison, Amnesic Shellfish Poison) were found in mussels. E.coli was present with the highest concentration in February (16000 MPN/100g e.p.). Salmonella and Vibrio spp. have not been detected. Almost a microplastic per grams was found, mainly fiber of different colours. Further studies, carried out for several months, will allow to better understand the possible problems related to the production of mussels in a lagoon not yet classified as a shellfish production area.

Differences in the Structure and Diversity of Invertebrate Assemblages Harbored by an Intertidal Ecosystem Engineer between Urban and Non-Urban Shores

Nowadays, coastal urbanization is one of the most serious and prevalent pressures on marine ecosystems, impacting their biodiversity. The objective of this study was to explore differences in attributes and biodiversity associated with an intertidal ecosystem engineer, the mussel Mytilus galloprovincialis Lamarck, 1819 between urban and non-urban shores. For this, mussel attributes and their associated macrofauna were compared between urban and non-urban rocky shores in the north of Portugal. Results showed that the largest sized mussels were more frequent on urban shores, whereas the smallest size class was only present in non-urban shores. Regarding macrofauna associated with mussels, the number of taxa was significantly higher on non-urban shores. Moreover, the structure of the macrobenhic assemblages was significantly different between urban and non-urban shores. Most important taxa responsible for differences were more abundant on non-urban shores except for Nucella lapillus, Idotea pelagica and Oligochaeta that were more abundant on urban shores. Therefore, our results showed that the mussel size frequency and the structure of the associated macrobenthic assemblages changed in urban shores. Considering the relevance of mussel beds for biodiversity and human well-being, our results indicate the need of adopting proper management plans to minimize these effects on urban intertidal ecosystems.

Ecological state of the environment and phenotypic characteristics of mussel Mytilus galloprovincialis Lamarck, 1873 in the Neum Bay (Bosnia and Herzegovina)

Mytilis galloprovincialis Lamarck, 1873 is a species widespread in the Adriatic Sea. Due to the its edibility, it is the first shellfish breed in Europe, and two farms have been registered in the Neum Bay. The paper analyzes native mussel populations of M. galloprovincialis from three populations (Neum Bay two and Mali Ston Croatia). For the purposes of the analysis, sampling was performed in the tide zone in May 2019. According to the WFD and typology, these three localities are in the type of coastal waters of polyhialine with fine-grained sediment. According to the average values ​​of physical-chemical and chlorophyll, Neum Bay is in the category of good ecological status, while Mali Ston is stated to be a reference site. Morphometric measurements of the right eyelid in 90 individuals (30 per locality) included external parameters (height, total length and width of the shell) as well as total weight, gut weight and shell weight. As the internal parameters, the characteristics of the ligament, retractor muscles and adductor muscles are analyzed. By the application of statistical analyzes (descriptive statistics, post Hoc analysis, correlation and descriptive statistics), differences in the total weight, length and parameters of the adductor and retractor muscles have been determinated. The species from Mali Ston are clearly separated from the species of the Neum Bay, which indicates more pronounced anthropogenic influences in the areas of the Neum town. Morphometric analysis is a powerful tool in monitoring the state of populations and in combination with genetic-molecular analysis can indicate changes in the environment. Determining pathogens in mussel species in Croatia, Slovenia and Italy is an impulse to control the condition of natural and breeding species, using various methods and analyzes.  

Analysis of the Dynamics of Marine Structures and Species with Criterial Mathematical Models

The influence of the area of artificial substrates (collectors) on the biological parameters of populations of mussels (Mytilus galloprovincialis Lamarck) during their cultivation in the Black Sea has been investigated. For growing mollusks, four types of collectors were used, with different relative areas (ω), i.e., with different ratios of the substrate area (S) per unit length of the collector (L), which were 0.09, 0.21, 0.34, and 0.55. It was found that, during a 1.5-year cultivation, the density (N, ind./m) and biomass (B, kg/m) change and reach a certain stationary state, determined by the relative area of the substrate. It was shown that, on collectors with a higher value of ω, there was a decrease in the average length (L, mm) and weight (W, g) of the mollusk yield. The Boysen–Jensen method was used to calculate the total production of mollusks (P), elimination (E), and specific production (P/B coefficient) for each type of reservoir, and it was shown that P increased with an increase in the substrate area, while E and P/B coefficients decreased. Based on the analysis of the obtained results, it was concluded that during the cultivation of mussels these parameters are regulated by density-dependent population factors (intraspecific competition) for space (substrate) and food.

Autecology of benthic diatom Striatella unipunctata (Lyngbye) C. A. Agardh, 1832 – indicator of organic water pollution (Black Sea and Sea of Japan)

Analysis of long-term data (1987–2019) was carried out on the morphology and autecology of the benthic colonial large-cell species Striatella unipunctata (Lyngbye) C. A. Agardh, 1832 in the microphytobenthos of the Black Sea and Sea of Japan, including water areas of specially protected natural areas of Russia. The species is widely found on natural and artificial substrates in the Black Sea year-round, and in the Sea of Japan, at a water temperature down to −1.5 °C. St. unipunctata quantitative data were determined by direct cell counting in the Goryaev camera under light microscopes (LMs) Biolam L-212, Axioskop 40, and Olympus BX41. Species morphology, phytogeography, and ecology are described. The cell size range of populations is presented: for the Black Sea, valves 25–148 µm long, 8–22 µm wide, frustules 36.3–50.4 µm wide, 18–24 fibulae in 10 µm, and 7–8 girdle bands in 10 µm; for the Sea of Japan, valves 85–125 µm long, 12–21 µm wide, 7–8 girdle bands in 10 µm, 20–25 fibulae in 10 µm, frustules 32.0–34.3 µm long, 10–11 µm wide, and 25 fibulae in 10 µm. For the first time, St. unipunctata valves and frustules were studied in vivo under LMs, and frustule ultrastructure, under a scanning electron microscope (SEM). For the first time, quantitative indicators of the species populations from the Black Sea and Sea of Japan were compared. The morphology of the frustule ultrastructure of St. unipunctata was studied under a Hitachi SEM, model SU3500 (Japan), in Leica EM ACE200 gold-palladium-coated samples. In the Kazachya Bay of the Black Sea near the Oceanarium, the absolute maximum abundance was recorded – 41.6·10³ cells·cm−2 with a biomass of 1.73 mg·cm−2 in January (t = +6.9 °C) in the epizoon of the cultured mussel Mytilus galloprovincialis Lamarck, 1819 at a depth of 0.5 m at excessive organic pollution of water. The minimum values were of 0.26·10³ cells·cm−2 and 0.011 mg·cm−2, respectively, in July (t = +23.5 °C) at a depth of 2.5 m. In the Paris Bay (Russky Island) of the Sea of Japan in the water area of the Marine Mammal Research Base of the Primorsky Oceanarium (Vladivostok), the abundance in the asbestos plates periphyton was of 207·10³ cells·cm−2 in the summer. For the first time, unique micrographs of the species in vivo were obtained under a LM, and of purified frustules – under a SEM.

Investigation of microplastics in edible wild mussels from İzmir Bay (Aegean Sea, Western Turkey): A risk assessment for the consumers

The presence of microplastics (MPs) was determined in Mediterranean mussel (Mytilus galloprovincialis Lamarck, 1819) and grooved carpet shell (Ruditapes decussatus Linnaeus, 1758) together with water samples from in İzmir Bay (Aegean Sea, Western Turkey). A total of 895 MPs from Karşıyaka (Station 1), and 787 MPs from Gülbahçe (Station 2) were detected in 60 mussel samples, giving a total content of 1682 MPs. In water samples, a total of 545 MPs were detected in samples from Station 1 and 1287 MPs in samples from Station 2 (1832 MPs total). The amount of MPs in water samples was less in Station 1 than in Station 2. This difference is probably caused by Çiğli Wastewater Treatment Plant (WWTP) located near Station 1. Public health risk assessment on the consumption of the species M. galloprovincialis revealed that 70.82 items person−1 year−1 MPs through this species could enter consumers' digestive systems.