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Corfu Island (Greece) is located in the northern Ionian Sea and exhibits unique and diverse marine coastal habitats suitable for high-diversity assemblages such as shallow-water foraminifera. The island also lies near the current range expansion front of the invasive species Amphistegina lobifera. We analyzed the foraminiferal assemblages of 51 samples from 25 sites around the island, calculated diversity indices, and analyzed the community structures of foraminiferal assemblages in comparison to local environmental variables. In addition to that, using the spatial structure or relative abundances, we evaluated the effect of A. lobifera on the species richness of all benthic foraminifera and habitat-specific groups. With 200 benthic foraminiferal species found, the high species richness and other diversity indices indicate Corfu as an area of high diversity. The main ecological drivers for the assemblage compositions were water depth, sediment texture, and habitat (especially vegetation), resulting in three main assemblage clusters around the island: (1) sandy or rocky, shallow-water areas from the south and west; (2) deeper areas from the west; and (3) rocky, vegetated areas of variable depths from the northwest and northeastern parts of the island. Our analyses suggest that the invasive species A. lobifera affects local diversity of the foraminiferal assemblage and that these effects become apparent when the invasive species accounts for more than 10 %–20 % of the total abundance. We also observed significant negative correlations with sessile epiphytes and smaller miliolids. Both groups share similar microhabitats with A. lobifera and might be outcompeted, which is probably further facilitated by ongoing ocean warming. However, other warm-affiliated taxa (e.g., other symbiont-bearing species) initially show a positive correlation with the increasing presence of A. lobifera until the latter exceeds 20 %. We expect that A. lobifera and other warm-adapted species will play an increasing role in shaping future biodiversity and assemblage composition in this area, a feature that supports the prognosed tropicalization of the Mediterranean Sea.

To enrich spatio-temporal information on the distribution of alien, cryptogenic, and neonative species in the Mediterranean and the Black Sea, a collective effort by 173 marine scientists was made to provide unpublished records and make them open access to the scientific community. Through this effort, we collected and harmonized a dataset of 12,649 records. It includes 247 taxa, of which 217 are Animalia, 25 Plantae and 5 Chromista, from 23 countries surrounding the Mediterranean and the Black Sea. Chordata was the most abundant taxonomic group, followed by Arthropoda, Mollusca, and Annelida. In terms of species records, Siganus luridus, Siganus rivulatus, Saurida lessepsianus, Pterois miles, Upeneus moluccensis, Charybdis (Archias) longicollis, and Caulerpa cylindracea were the most numerous. The temporal distribution of the records ranges from 1973 to 2022, with 44% of the records in 2020–2021. Lethrinus borbonicus is reported for the first time in the Mediterranean Sea, while Pomatoschistus quagga, Caulerpa cylindracea, Grateloupia turuturu, and Misophria pallida are first records for the Black Sea; Kapraunia schneideri is recorded for the second time in the Mediterranean and for the first time in Israel; Prionospio depauperata and Pseudonereis anomala are reported for the first time from the Sea of Marmara. Many first country records are also included, namely: Amathia verticillata (Montenegro), Ampithoe valida (Italy), Antithamnion amphigeneum (Greece), Clavelina oblonga (Tunisia and Slovenia), Dendostrea cf. folium (Syria), Epinephelus fasciatus (Tunisia), Ganonema farinosum (Montenegro), Macrorhynchia philippina (Tunisia), Marenzelleria neglecta (Romania), Paratapes textilis (Tunisia), and Botrylloides diegensis (Tunisia)., peer-reviewed

Corfu Island (Greece) is located in the northern Ionian Sea and exhibits unique and diverse marine coastal habitats suitable for high diversity assemblages such as shallow-water foraminifera. The island also lies near the current range expansion front of the invasive species Amphistegina lobifera. We analyzed the foraminiferal assemblages of 51 samples from 25 sites around the island, calculated diversity indices, and analyzed the community structures of foraminiferal assemblages in comparison to local ecological variables. In addition to that, we evaluated the effect of A. lobifera on the species richness of all benthic foraminifera and habitat-specific groups. With 200 benthic foraminiferal species found, the high species richness and other diversity indices indicate Corfu as an area of high diversity. The main ecological drivers for the assemblage compositions were water depth, sediment texture, and habitat (especially vegetation), resulting in 3 main assemblage-clusters around the Island: 1) sandy or rocky, shallow-water areas from the south and west, 2) deeper areas from the west and 3) rocky, vegetated areas of variable depths from the northwest and northeastern parts of the island. We show that the invasive species A. lobifera affects local diversity as soon as it exceeds 20% of the total benthic foraminiferal assemblage. We also observed significant negative correlations with sessile epiphytes and smaller miliolids. Both groups share similar microhabitats with A. lobifera and might be outcompeted, which is probably further facilitated by ongoing ocean warming. However, other warm-affiliated taxa (e.g., other symbiont-bearing species) initially show a positive correlation with the increasing presence of A. lobifera until the latter exceeds 20%. We expect that A. lobifera and other warm-adapted species will play an increasing role in shaping future biodiversity and assemblage composition in this area, a feature that supports the prognosed tropicalization of the Mediterranean Sea.

The MagellanPlus workshop “BlackGate” addressed fundamental questions concerning the dynamic evolution of the Mediterranean–Black Sea (MBS) gateway and its palaeoenvironmental consequences. This gateway drives the Miocene–Quaternary circulation patterns in the Black Sea and governs its present status as the world's largest example of marine anoxia. The exchange history of the MBS gateway is poorly constrained because continuous Pliocene–Quaternary deposits are not exposed on land adjacent to the Black Sea or northern Aegean. Gateway exchange is controlled by climatic (glacio-eustatic-driven sea-level fluctuations) and tectonic processes in the catchment as well as tectonic propagation of the North Anatolian Fault Zone (NAFZ) in the gateway area itself. Changes in connectivity trigger dramatic palaeoenvironmental and biotic turnovers in both the Black Sea and Mediterranean domains. Drilling a Messinian to Holocene transect across the MBS gateway will recover high-amplitude records of continent-scale hydrological changes during glacial–interglacial cycles and allow us to reconstruct marine and freshwater fluxes, biological turnover events, deep biospheric processes, subsurface gradients in primary sedimentary properties, patterns and processes controlling anoxia, chemical perturbations and carbon cycling, growth and propagation of the NAFZ, the timing of land bridges for Africa and/or Asia–Europe mammal migration, and the presence or absence of water exchange during the Messinian salinity crisis. During thorough discussions at the workshop, three key sites were selected for potential drilling using a mission-specific platform (MSP): one on the Turkish margin of the Black Sea (Arkhangelsky Ridge, 400 m b.s.f., metres below the seafloor), one on the southern margin of the Sea of Marmara (North İmrali Basin, 750 m b.s.f.), and one in the Aegean (North Aegean Trough, 650 m b.s.f.). All sites target Quaternary oxic–anoxic marl–sapropel cycles. Plans include recovery of Pliocene lacustrine sediments and mixed marine–brackish Miocene sediments from the Black Sea and the Aegean. MSP drilling is required because the JOIDES Resolution cannot pass under the Bosporus bridges. The wider goals are in line with the aims and scope of the International Ocean Discovery Program (IODP) “2050 Science Framework: Exploring Earth by Scientific Ocean Drilling” and relate specifically to the strategic objectives “Earth's climate system”, “Tipping points in Earth's history”, and “Natural hazards impacting society”.

The MagellanPlus workshop "BlackGate"addressed fundamental questions concerning the dynamic evolution of the Mediterranean-Black Sea (MBS) gateway and its palaeoenvironmental consequences. This gateway drives the Miocene-Quaternary circulation patterns in the Black Sea and governs its present status as the world's largest example of marine anoxia. The exchange history of the MBS gateway is poorly constrained because continuous Pliocene-Quaternary deposits are not exposed on land adjacent to the Black Sea or northern Aegean. Gateway exchange is controlled by climatic (glacio-eustatic-driven sea-level fluctuations) and tectonic processes in the catchment as well as tectonic propagation of the North Anatolian Fault Zone (NAFZ) in the gateway area itself. Changes in connectivity trigger dramatic palaeoenvironmental and biotic turnovers in both the Black Sea and Mediterranean domains. Drilling a Messinian to Holocene transect across the MBS gateway will recover high-amplitude records of continent-scale hydrological changes during glacial-interglacial cycles and allow us to reconstruct marine and freshwater fluxes, biological turnover events, deep biospheric processes, subsurface gradients in primary sedimentary properties, patterns and processes controlling anoxia, chemical perturbations and carbon cycling, growth and propagation of the NAFZ, the timing of land bridges for Africa and/or Asia-Europe mammal migration, and the presence or absence of water exchange during the Messinian salinity crisis. During thorough discussions at the workshop, three key sites were selected for potential drilling using a mission-specific platform (MSP): one on the Turkish margin of the Black Sea (Arkhangelsky Ridge, 400mb.s.f., metres below the seafloor), one on the southern margin of the Sea of Marmara (North Imrali Basin, 750mb.s.f.), and one in the Aegean (North Aegean Trough, 650mb.s.f.). All sites target Quaternary oxic-anoxic marl-sapropel cycles. Plans include recovery of Pliocene lacustrine sediments and mixed marine-brackish Miocene sediments from the Black Sea and the Aegean. MSP drilling is required because the JOIDES Resolution cannot pass under the Bosporus bridges. The wider goals are in line with the aims and scope of the International Ocean Discovery Program (IODP) "2050 Science Framework: Exploring Earth by Scientific Ocean Drilling"and relate specifically to the strategic objectives "Earth's climate system", "Tipping points in Earth's history", and "Natural hazards impacting society".