Functional and conservation relevance of Savalia savaglia in the Turkish Straits System: First record from the North Aegean coasts of Turkey and new mesophotic habitats in the Sea of Marmara

Functional and conservation relevance of Savalia savaglia in the Turkish Straits System: First record from the North Aegean coasts of Turkey and new mesophotic habitats in the Sea of Marmara | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Short Report Functional and conservation relevance of Savalia savaglia in the Turkish Straits System: First record from the North Aegean coasts of Turkey and new mesophotic habitats in the Sea of Marmara H. Barış Özalp, Senem Onen Tarantini This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6854315/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 6 You are reading this latest preprint version Abstract Trait-based approaches are widely used in ecology to monitor and understand how communities and ecosystems respond to human-driven environmental impacts. Savalia savaglia , a rarely encountered parazoanthid coral species, is a key ecosystem engineer in the Mediterranean mesophotic zone. This study presents the first morphologically verified records from the North Aegean Sea coast of Turkey and new habitat data from the Turkish Straits System, including the Sea of Marmara. Field surveys documented four major reef systems with 80 associated benthic invertebrates, two of which are new records for the Marmara Sea. Morphological assessments revealed exceptionally large colonies and previously undocumented cases of parasitic and autonomous growth. Observations also represent the first finding of seine net damage and anchoring threats ever recorded in the Turkish Seas. Our results highlight the urgent need for coral-focused marine protected areas to safeguard biodiversity and mitigate anthropogenic pressures. Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Introduction The gold coral, also known as the false black coral Savalia savaglia (Bertoloni, 1819), a rarely encountered parazoanthid coral species with a three-dimensional growth character, plays a crucial role in the Mediterranean mesophotic zone. Being a characteristic zoanthid coral of the Mediterranean Sea, the species is also widely distributed in many regions in the western Atlantic (Ocaña & Brito, 2004 ; Altuna et al., 2010; Giusti et al., 2015 ; Mačić et al., 2024 ), although there is still a lack of information of northernmost occurrences beyond the Mediterranean Sea. It primarily inhabits the mesophotic zone, a low light environment typically found below 30 meters depth. This zone specifically serves as a refuge area for the specimen. While it is typically found within the Mediterranean and North Atlantic regions circalittoral zone, it has been reported to form habitats at depths of up to 900 meters. Primarily inhabiting hard substrates deeper than the mesophotic, this coral species has also been recorded in shallower waters at some specific regions (Giusti et al, 2015 ). Dense populations are found in the northwestern Mediterranean and eastern Atlantic (Rossi, 1958 ). Ecologically, the complex structure of S. savaglia colonies creates a critical habitat, supporting the feeding, nursing and breeding of numerous species. As a substrate builder specimen, it enhances biodiversity and creates high biodiversity sites in certain spots (Verdura et al, 2019 ; Canessa et al, 2024 ). The current study is the first detailed record within North Aegean Sea coasts of Turkey and provides unique data regarding some rare new hotspots in the Sea of Marmara, revealing particularly rare and large white S. savaglia colonies. The study also aims to provide a preliminary assessment of Savalia savaglia colonies in the Marmara Sea, investigating their distribution, depth range, and morphological characteristics. Within the scope of the research, a total of 80 benthic invertebrate species, two of which are newly reported, as the associated biota around the coral habitat is given from the region for the first time. The research documents the four largest, uncommon reef sites of S. savaglia in the Turkish Straits System (Çanakkale Strait, Marmara Sea and the North Aegean Sea coasts of Turkey) with their morphometric dimension. Mesophotic zones are twilight environments typically between 30–150 metres (can be deeper regarding water clarity) that serve as transitional habitats between shallow and deep sea. This zone hosts a variety of species; photosynthetic organisms like algae and symbiotic corals are mostly present in the upper mesophotic zone. Meanwhile deeper areas are dominated by sponges, non-photosynthetic corals, and other filter-feeders. This zone specially serves as a refuge area for coral colonies since it is protected by shallow water stress factors. Unlike many Anthozoa, S. savaglia exhibits parasitic growth, often colonizing unhealthy or necrotic branches of sea-fans. It initiates growth on weakened or dead branches of previous-generation fan corals, subsequently spreading across the entire skeleton via histidine protein secretion. Notably, S. savaglia is a rare zoanthid with the unique ability to produce its own hard skeleton independently of a host. It typically colonizes the branches of corals such as Eunicella , Paramuricea , and Anthipathes . Savalia savaglia can exhibit both parasitic and natural growth characteristics (Ocaña et al., 1995 ). Recent studies in the Çanakkale Strait and the Sea of Marmara have revealed individuals colonizing various gorgonian species, as well as colonies that have established themselves independently by forming their own basal skeletal structure on substrate (Özalp, 2023). Given its rarity and ecological importance this coral species is protected under Annex II of both the Barcelona Convention (ASPIM) and the Bern Convention (Cerrano et al., 2010 ). In addition to documenting new populations, this study also reports the first observed cases of engulfment behaviour in the region. Ten different colonies of S. savaglia were recorded growing over Paramuricea clavata skeletons in the Çanakkale Strait and Marmara Island, indicating parasitic growth over live or dead branches of gorgonians. Five additional colonies were found growing independently, forming their own skeletal structures, a rare trait among zoanthids. Colonies displaying engulfment had thinner trunks and lateral spread, whereas self-supporting individuals exhibited thicker, more robust morphologies. These findings highlight both the structural plasticity and ecological strategies of S. savaglia , enabling its persistence across varying mesophotic environments. This also underscores the importance of the Sea of Marmara as a potential hotspot for this species, a region that remains largely unstudied in this context. Material and Methods Underwater research (named KUZEYADA marine surveys) three different regions Marmara Island, the Çanakkale Strait, and the North Aegean Sea (Babakale) was performed by means of SCUBA and technical diving across eight stations (Fig. 1 ). In this context, the main largest spreading areas of Savalia savaglia (Cinarli, Avsa offshore, Hayirsiz Islet, Nara, Babakale) (Fig. 2 , 3 , 4 , 5 ; supp. file 1) were firstly examined. Initially, potential coral sites were surveyed using the manta-tow technique conducted by the Scientific Diving Research Team at Çanakkale Onsekiz Mart University (ÇOMÜ), followed by GPS-based marking of specific S. savaglia colonies for further investigation. Coral dominance and associated biota were documented using visual census techniques along 50 m transects at depths ranging from 38 to 56 meters. Rocky substrates with dense S. savaglia occurrence were also recorded using underwater two separates’ cameras. The sampled material (corals, video footage captured by divers. Sampling included coral colonies and associated benthic fauna (sponges, tunicates, molluscs, phoronids, and polychaetes), which were deposited in the /Water Quality Laboratory at Marine Science and Technology Faculty ÇOMÜ for taxonomic identification. Marine surveys were conducted as part of three different research projects completed between 2016 and 2022: UNDP-GEF2022, ProjectSavalia2018/72ozalp, and TUBITAK-116Y030 that given Table 1 . Table 1 Summary of survey sites, key species findings, and habitat characteristics. Site Code Location Name Coordinates Depth (m) Substrate Type Associated Habitat Key Species Found Sample Size Project / Year MAR-1 Marmara Island (Lazkaya) 40°34’31”N – 27°33’06”E 34 Calcium carbonate overhang Coralligenous & Scleractinian corals T. citrina 7 ind. TUBITAK 116Y030 / 2018 MAR-2 Avşa Offshore (AOR) 40°35’52”N – 27°31’39”E 38–49 Rocky Neophycnodonte cochlear , gorgonians S. savaglia 6 col. UNDP-GEF / 2022 MAR-3 Hayırsız Island (HIR) 40°38’59”N – 27°28’59”E 49 Rocky Gorgonian facies S. savaglia 3 col. UNDP-GEF / 2022 ÇST Nara (Çanakkale Strait) 40°11’53”N – 26°33’36”E 38–40 Rocky Gorgonians S. savaglia 3 col. UNDP-GEF / 2022 AEGEAN Babakale – Assos 39°27’38”N – 26°03’06”E 56 Rocky Deep reef S. savaglia (giant) 1 col. Project SAVALIA / 2018 MAR-4 Marmara Island 40°39’24”N – 27°32’52”E 26 Rocky Coralligenous & Cerianthus P. australis 3 col. TUBITAK 116Y030 / 2018 A total of 186 coral colonies were observed across the study area. Morphological parameters (colony height, width, trunk diameter, and basal circumference) were measured in situ for 40 representative colonies using a flexible meter tape and photographic analysis with scale indicators. Colonies were categorized into three types based on structural growth: (1) juvenile-to-adult growing individuals, (2) colonies growing on existing S. savaglia skeletons (Marmara Island, Çanakkale Strait, Aegean Sea), and (3) engulfing colonies observed on Paramuricea clavata (Çanakkale Strait and Marmara Island) In the site surveys, a total area of 1560 square meters was examined. Transect-supported visual census yielded 107 colonies per 700 m² in the Avşa Offshore Region (AOR), 56 colonies/400 m² in the Cinarli Region (CR), and 23 colonies/460 m² in the Hayırsız Island Region (HIR). Among them, engulfing colonies were found only in the Çanakkale Strait and Marmara Island stations. Morphometric comparisons between engulfing and free-growing colonies showed significant variation, with free-standing individuals displaying larger trunk diameters and basal thickness, particularly in the Cinarli and Nara sites. The current work also represents the first report of engulfment action encountering from 10 different colonies of Paramuricea clavata in the Çanakkale Strait and the Sea of Marmara (Marmara Island). Morphometric details are further summarized in Table 2 . Results and Discussion This study documents the largest Savalia savaglia colonies ever recorded in Turkish waters, with some individuals surpassing previous Mediterranean records in both height and basal width. For example, colony heights of up to 133 cm and basal widths exceeding 139 cm were documented measurements that surpass those reported by Gaglioti et al. ( 2019 ) from Ustica Island. Additionally, trunk diameters exceeded the 14 cm record by Bell ( 1891 ), highlighting the exceptional size and potential age of these specimens. The remarkable size of these colonies suggests an old age, which is consistent with previous estimates of extremely slow growth rates for Savalia species. Cerrano et al. ( 2010 ) and Roark et al. ( 2006 ) estimated growth rates between 14–45 µm/year with the skeleton character dating back to 2700 years, while Grigg (2002) reported a colony with a 2.6 m trunk corresponding to approximately 70 years of age. While precise age estimation is beyond the scope of this study, the morphometric parameters reported here provide strong evidence for the long-lived nature of the observed colonies. Morphometric characters of Savalia savaglia measured at the stations are given Table 2 . Table 2 Morphometric characters of Savalia savaglia measured at the stations. COLONY Station/Depth Maximum Height / Width Trunk Diameter Basal Circumference CST-1 Eceabat/42 m 117/104 cm 13.2 cm 26.4 cm CST-2A Nara/40 m 80.2/70 cm 10 cm 6 cm CST-2B Nara/40 m 69/12 cm 8 cm > 5 cm CST-3 Nara/38 m 57/18.5 cm 6.5 cm 7.1 cm Mar-1 Cinarli/42 m 50/96.4 cm 16.4 cm 22 cm Mar-2 Cinarli/42 m 53/62.8 cm 9 cm 8.5 cm Mar-3 Cinarli/41 m 62/70.5 cm 11.2 cm 22 cm Mar-4 AOR/44 m 62/34 cm 6.4 cm 4.5 cm Mar-5 AOR/37 m 18/13 cm 5.1 cm 9 cm Mar-6 HIR/46.8 m 49/60 cm 10 cm 16 cm AS-1 AS/56 m 133/139 cm > 18 cm > 20 cm ÇST: Çanakkale Strait, Mar: Marmara Island, AS: Aegean Sea, AOR: Avsa offshore region, HIR: Hayirsiz Island CST-2: the damaged separate colonies recorded as in closely associated with each other on the same rock, separate trunks and branches. Our findings also highlight notable structural diversity among colonies. Colonies forming their own skeletons exhibited greater thickness and basal spread, whereas those showing engulfment behaviour on Paramuricea clavata had more elongated, narrower profiles. This plasticity in growth forms likely reflects adaptive strategies in response to substrate type, light availability, and competition (Fig. 2 ). The study also reports, for the first time, the co-occurrence of Phoronis australis and Tethya citrina in the coral facies of the Marmara Sea. These findings expand the known distribution of both species and highlight the role of S. savaglia colonies as biodiversity hotspots. Notably, P. australis was observed closely associated with cerianthid-dominated Coralligenous habitats, whilst- T. citrina was found in calcium carbonate overhangs near S. savaglia (Fig. 3 ). Phylum: PORIFERA Class: Demospongiae Order: Tethyida Family: Tethyidae Species: Tethya citrina Sarà & Melone, 1965 Remarks: First record from the Sea of Marmara; observed on a calcium carbonate overhang near S. savaglia colonies. Phylum: CNIDARIA Class: Hexacorallia Order: Zoantharia Suborder: Macrocnemina Family: Parazoanthidae Species: Savalia savaglia (Bertoloni, 1819) Remarks: First confirmed record from the North Aegean coasts of Turkey and new mesophotic reef sites in the Sea of Marmara. Phylum: PHORONIDA Class: Phoronata Order: Phoronida Family: Phoronidae Species: Phoronis australis Haswell, 1883 Remarks: First record from the Sea of Marmara; found in coralligenous habitats associated with Cerianthus membranaceus The impact of anthropogenic threats on S. savaglia habitats was also quantified. Out of 186 surveyed coral colonies (Fig. 4 ), 60 were found dead, and six S. savaglia colonies showed physical damage likely caused by discarded seine nets. In the Avşa Offshore region, 84 dead colonies of Paramuricea clavata were documented, and anchoring activities were observed to cause severe fragmentation. This marks the first evidence of seine net impacts on S. savaglia in the region (Fig. 5 ), underscoring the urgency of marine conservation actions. Marmara Sea (Marmara Island). Conclusion Ultimately, the documentation of novel occurrences in the North Aegean Sea (Turkey), specifically rare morphologies and previously unrecorded species, alongside evidence of habitat degradation attributed to cumulative anthropogenic pressures (e.g., seine fishing, illegal fishing, and anchoring), demonstrates a critical requirement for targeted conservation initiatives. The creation of a coral-focused marine protected area in the Marmara Sea, particularly near Marmara Island, is crucial for the preservation of these unique mesophotic communities, especially when supported by robust regulations targeting destructive practices. Continued long-term monitoring and increased public awareness will be essential in safeguarding this vulnerable ecosystem. The findings of this study underscore the ecological importance and conservation urgency of Savalia savaglia habitats within the Turkish Straits System and adjacent North Aegean Sea. By documenting exceptional colony sizes, rare morphological traits, new species associations, and human-induced damages, this research emphasizes the necessity of immediate conservation action. A coral-specific marine protected area would provide much-needed legal and ecological safeguards for the region’s mesophotic biodiversity. Moreover, this study serves as a call for integrated monitoring, stakeholder involvement, and adaptive management practices to ensure the resilience and sustainability of these unique marine ecosystems. Declarations Supplementary Material Supplementary material includes an underwater video documenting one of the largest observed Savalia savaglia ) and gorgonian forests enhance colonies recorded in the studied regions. This video provides the first visual confirmation of the colony’s morphological traits and its associated benthic biodiversity and ecosystem functioning in the Turkish seas. Acknowledgements The authors express their sincere gratitude to Mr. Volkan Artut and Mr. Evren Göçen for his professional diving support during the UNDP Project 2022, and to Mr. Ömer Altuncu for his assistance as a guide diver. We also thank Mr. A. Hakan Eğilmez, Lecturer and technical diving instructor, and Mr. Barkın İren of the ABZU Technical Diving Team for their valuable contributions and for providing video documentation of a giant Savalia savaglia colony observed during scientific deep dives in the Babakale region. References Altuna, A, & Poliseno, A. (2019). 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Mediterranean Sea shelters for the gold coral Savalia savaglia (Bertoloni, 1819): An assessment of potential distribution of a rare parasitic species. Marine Environmental Research, 179,105686. doi: 10.1016/j.marenvres.2022.105686 Roark, E. B., Guilderson, T. P., Dunbar, R. B., & Ingram, B. L. (2006). Radiocarbon-based ages and growth rates of Hawaiian deep-sea corals. Marine Ecology Progress Series, 327, 1–4. doi: 10.3354/meps327001 Rossi L (1958) Primo rinvenimento di Gerardia savaglia (Bert) (Zoantharia) nei mari italiani (Golfo di Genova). Doriana 2(85): 8 pp Verdura, J., Linares, C., Ballesteros, E.. Coma, R, Uriz, M. J., Bensoussan, N., & Cebrian, E. (2019). Biodiversity loss in a Mediterranean ecosystem due to an extreme warming event unveils the role of an engineering gorgonian species. Scientific Reports, 9, 5911. doi: 10.1038/s41598-019-41929-0 Yavuz, A. (2022). Ghost nets Marmara Sea. https://www.hurriyetdailynews.com/over-320-000-square-meters-of-ghost-net-collected-from-marmara-sea-179376. Accessed on 12 January, 2025. Supplementary file 1 Supplementary video, is not available with this version. Cite Share Download PDF Status: Under Review Version 1 posted Reviewers agreed at journal 18 Nov, 2025 Reviewers invited by journal 11 Aug, 2025 Editor invited by journal 28 Jul, 2025 Editor assigned by journal 27 Jul, 2025 First submitted to journal 25 Jul, 2025 Editorial decision: Major Revisions Needed 17 Jul, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6854315","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Short Report","associatedPublications":[],"authors":[{"id":498583583,"identity":"8084c6b0-79d1-443f-be9b-e859e09a0218","order_by":0,"name":"H. 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A: \u003cem\u003eTethys citrina\u003c/em\u003e found on a Scleractinian coral-rich overhang, B: \u003cem\u003ePhoronis australis\u003c/em\u003e found closely associated with the colony of \u003cem\u003eCerianthus membranaceus\u003c/em\u003e around coralligenous formations.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-6854315/v1/33ecdc658bd7f848855d3c6b.png"},{"id":89380160,"identity":"58c9dfb4-2d43-45ca-910c-093d10884cad","added_by":"auto","created_at":"2025-08-19 11:42:23","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":1025669,"visible":true,"origin":"","legend":"\u003cp\u003eThe damaged colonies: A. CST-2A due to longline fishing B. CST-2B studied in Nara region (Çanakkale Strait).\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-6854315/v1/776c3c750e43eb3097e1fcaf.png"},{"id":89380163,"identity":"56e1c416-3b83-4c8f-9f5d-7cc744dbdde6","added_by":"auto","created_at":"2025-08-19 11:42:23","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":1561723,"visible":true,"origin":"","legend":"\u003cp\u003eA heavy seine net on \u003cem\u003eSavalia savaglia\u003c/em\u003e B. Severe impact of a discarded seine net recorded on \u003cem\u003eSavalia savaglia\u003c/em\u003e colonies, C. Ghost gear on \u003cem\u003eSavalia savaglia\u003c/em\u003e\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-6854315/v1/13b42419ea01715c60169030.png"},{"id":89382037,"identity":"42b2ce73-b497-4f5a-953e-2399c9d66099","added_by":"auto","created_at":"2025-08-19 12:06:35","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":11759294,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6854315/v1/fd5ab0fb-b386-4ec4-bcf1-3457ebc9d961.pdf"}],"financialInterests":"","formattedTitle":"Functional and conservation relevance of Savalia savaglia in the Turkish Straits System: First record from the North Aegean coasts of Turkey and new mesophotic habitats in the Sea of Marmara","fulltext":[{"header":"Introduction","content":"\u003cp\u003eThe gold coral, also known as the false black coral \u003cem\u003eSavalia savaglia\u003c/em\u003e (Bertoloni, 1819), a rarely encountered parazoanthid coral species with a three-dimensional growth character, plays a crucial role in the Mediterranean mesophotic zone. Being a characteristic zoanthid coral of the Mediterranean Sea, the species is also widely distributed in many regions in the western Atlantic (Oca\u0026ntilde;a \u0026amp; Brito, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2004\u003c/span\u003e; Altuna et al., 2010; Giusti et al., \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2015\u003c/span\u003e; Mačić et al., \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2024\u003c/span\u003e), although there is still a lack of information of northernmost occurrences beyond the Mediterranean Sea. It primarily inhabits the mesophotic zone, a low light environment typically found below 30 meters depth. This zone specifically serves as a refuge area for the specimen. While it is typically found within the Mediterranean and North Atlantic regions circalittoral zone, it has been reported to form habitats at depths of up to 900 meters. Primarily inhabiting hard substrates deeper than the mesophotic, this coral species has also been recorded in shallower waters at some specific regions (Giusti et al, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2015\u003c/span\u003e). Dense populations are found in the northwestern Mediterranean and eastern Atlantic (Rossi, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e1958\u003c/span\u003e). Ecologically, the complex structure of \u003cem\u003eS. savaglia\u003c/em\u003e colonies creates a critical habitat, supporting the feeding, nursing and breeding of numerous species. As a substrate builder specimen, it enhances biodiversity and creates high biodiversity sites in certain spots (Verdura et al, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e2019\u003c/span\u003e; Canessa et al, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2024\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eThe current study is the first detailed record within North Aegean Sea coasts of Turkey and provides unique data regarding some rare new hotspots in the Sea of Marmara, revealing particularly rare and large white \u003cem\u003eS. savaglia\u003c/em\u003e colonies. The study also aims to provide a preliminary assessment of \u003cem\u003eSavalia savaglia\u003c/em\u003e colonies in the Marmara Sea, investigating their distribution, depth range, and morphological characteristics. Within the scope of the research, a total of 80 benthic invertebrate species, two of which are newly reported, as the associated biota around the coral habitat is given from the region for the first time. The research documents the four largest, uncommon reef sites of \u003cem\u003eS. savaglia\u003c/em\u003e in the Turkish Straits System (\u0026Ccedil;anakkale Strait, Marmara Sea and the North Aegean Sea coasts of Turkey) with their morphometric dimension.\u003c/p\u003e\u003cp\u003eMesophotic zones are twilight environments typically between 30\u0026ndash;150 metres (can be deeper regarding water clarity) that serve as transitional habitats between shallow and deep sea. This zone hosts a variety of species; photosynthetic organisms like algae and symbiotic corals are mostly present in the upper mesophotic zone. Meanwhile deeper areas are dominated by sponges, non-photosynthetic corals, and other filter-feeders. This zone specially serves as a refuge area for coral colonies since it is protected by shallow water stress factors. Unlike many Anthozoa, \u003cem\u003eS. savaglia\u003c/em\u003e exhibits parasitic growth, often colonizing unhealthy or necrotic branches of sea-fans. It initiates growth on weakened or dead branches of previous-generation fan corals, subsequently spreading across the entire skeleton via histidine protein secretion. Notably, \u003cem\u003eS. savaglia\u003c/em\u003e is a rare zoanthid with the unique ability to produce its own hard skeleton independently of a host. It typically colonizes the branches of corals such as \u003cem\u003eEunicella\u003c/em\u003e, \u003cem\u003eParamuricea\u003c/em\u003e, and \u003cem\u003eAnthipathes\u003c/em\u003e. \u003cem\u003eSavalia savaglia\u003c/em\u003e can exhibit both parasitic and natural growth characteristics (Oca\u0026ntilde;a et al., \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e1995\u003c/span\u003e). Recent studies in the \u0026Ccedil;anakkale Strait and the Sea of Marmara have revealed individuals colonizing various gorgonian species, as well as colonies that have established themselves independently by forming their own basal skeletal structure on substrate (\u0026Ouml;zalp, 2023). Given its rarity and ecological importance this coral species is protected under Annex II of both the Barcelona Convention (ASPIM) and the Bern Convention (Cerrano et al., \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2010\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eIn addition to documenting new populations, this study also reports the first observed cases of engulfment behaviour in the region. Ten different colonies of \u003cem\u003eS. savaglia\u003c/em\u003e were recorded growing over \u003cem\u003eParamuricea clavata\u003c/em\u003e skeletons in the \u0026Ccedil;anakkale Strait and Marmara Island, indicating parasitic growth over live or dead branches of gorgonians. Five additional colonies were found growing independently, forming their own skeletal structures, a rare trait among zoanthids. Colonies displaying engulfment had thinner trunks and lateral spread, whereas self-supporting individuals exhibited thicker, more robust morphologies. These findings highlight both the structural plasticity and ecological strategies of \u003cem\u003eS. savaglia\u003c/em\u003e, enabling its persistence across varying mesophotic environments. This also underscores the importance of the Sea of Marmara as a potential hotspot for this species, a region that remains largely unstudied in this context.\u003c/p\u003e"},{"header":"Material and Methods","content":"\u003cp\u003eUnderwater research (named KUZEYADA marine surveys) three different regions Marmara Island, the \u0026Ccedil;anakkale Strait, and the North Aegean Sea (Babakale) was performed by means of SCUBA and technical diving across eight stations (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). In this context, the main largest spreading areas of \u003cem\u003eSavalia savaglia\u003c/em\u003e (Cinarli, Avsa offshore, Hayirsiz Islet, Nara, Babakale) (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e, \u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e, \u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e, \u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e; supp. file 1) were firstly examined. Initially, potential coral sites were surveyed using the manta-tow technique conducted by the Scientific Diving Research Team at \u0026Ccedil;anakkale Onsekiz Mart University (\u0026Ccedil;OM\u0026Uuml;), followed by GPS-based marking of specific \u003cem\u003eS. savaglia\u003c/em\u003e colonies for further investigation.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eCoral dominance and associated biota were documented using visual census techniques along 50 m transects at depths ranging from 38 to 56 meters. Rocky substrates with dense \u003cem\u003eS. savaglia\u003c/em\u003e occurrence were also recorded using underwater two separates\u0026rsquo; cameras. The sampled material (corals, video footage captured by divers. Sampling included coral colonies and associated benthic fauna (sponges, tunicates, molluscs, phoronids, and polychaetes), which were deposited in the /Water Quality Laboratory at Marine Science and Technology Faculty \u0026Ccedil;OM\u0026Uuml; for taxonomic identification. Marine surveys were conducted as part of three different research projects completed between 2016 and 2022: UNDP-GEF2022, ProjectSavalia2018/72ozalp, and TUBITAK-116Y030 that given Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eSummary of survey sites, key species findings, and habitat characteristics.\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"9\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSite Code\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eLocation Name\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eCoordinates\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eDepth (m)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eSubstrate Type\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eAssociated Habitat\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003eKey Species Found\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c8\"\u003e\u003cp\u003eSample Size\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c9\"\u003e\u003cp\u003eProject / Year\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMAR-1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMarmara Island (Lazkaya)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e40\u0026deg;34\u0026rsquo;31\u0026rdquo;N \u0026ndash; 27\u0026deg;33\u0026rsquo;06\u0026rdquo;E\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e34\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eCalcium carbonate overhang\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003eCoralligenous \u0026amp; Scleractinian corals\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e\u003cem\u003eT. citrina\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e7 ind.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eTUBITAK 116Y030 / 2018\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMAR-2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eAvşa Offshore (AOR)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e40\u0026deg;35\u0026rsquo;52\u0026rdquo;N \u0026ndash; 27\u0026deg;31\u0026rsquo;39\u0026rdquo;E\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e38\u0026ndash;49\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eRocky\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cem\u003eNeophycnodonte cochlear\u003c/em\u003e, gorgonians\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e\u003cem\u003eS. savaglia\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e6 col.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eUNDP-GEF / 2022\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMAR-3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eHayırsız Island (HIR)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e40\u0026deg;38\u0026rsquo;59\u0026rdquo;N \u0026ndash; 27\u0026deg;28\u0026rsquo;59\u0026rdquo;E\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e49\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eRocky\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003eGorgonian facies\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e\u003cem\u003eS. savaglia\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e3 col.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eUNDP-GEF / 2022\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u0026Ccedil;ST\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eNara (\u0026Ccedil;anakkale Strait)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e40\u0026deg;11\u0026rsquo;53\u0026rdquo;N \u0026ndash; 26\u0026deg;33\u0026rsquo;36\u0026rdquo;E\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e38\u0026ndash;40\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eRocky\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003eGorgonians\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e\u003cem\u003eS. savaglia\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e3 col.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eUNDP-GEF / 2022\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAEGEAN\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eBabakale \u0026ndash; Assos\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e39\u0026deg;27\u0026rsquo;38\u0026rdquo;N \u0026ndash; 26\u0026deg;03\u0026rsquo;06\u0026rdquo;E\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e56\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eRocky\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003eDeep reef\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e\u003cem\u003eS. savaglia\u003c/em\u003e (giant)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e1 col.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eProject SAVALIA / 2018\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMAR-4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMarmara Island\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e40\u0026deg;39\u0026rsquo;24\u0026rdquo;N \u0026ndash; 27\u0026deg;32\u0026rsquo;52\u0026rdquo;E\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e26\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eRocky\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003eCoralligenous \u0026amp; \u003cem\u003eCerianthus\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e\u003cem\u003eP. australis\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e3 col.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eTUBITAK 116Y030 / 2018\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eA total of 186 coral colonies were observed across the study area. Morphological parameters (colony height, width, trunk diameter, and basal circumference) were measured in situ for 40 representative colonies using a flexible meter tape and photographic analysis with scale indicators. Colonies were categorized into three types based on structural growth: (1) juvenile-to-adult growing individuals, (2) colonies growing on existing \u003cem\u003eS. savaglia\u003c/em\u003e skeletons (Marmara Island, \u0026Ccedil;anakkale Strait, Aegean Sea), and (3) engulfing colonies observed on \u003cem\u003eParamuricea clavata\u003c/em\u003e (\u0026Ccedil;anakkale Strait and Marmara Island)\u003c/p\u003e\u003cp\u003eIn the site surveys, a total area of 1560 square meters was examined. Transect-supported visual census yielded 107 colonies per 700 m\u0026sup2; in the Avşa Offshore Region (AOR), 56 colonies/400 m\u0026sup2; in the Cinarli Region (CR), and 23 colonies/460 m\u0026sup2; in the Hayırsız Island Region (HIR). Among them, engulfing colonies were found only in the \u0026Ccedil;anakkale Strait and Marmara Island stations. Morphometric comparisons between engulfing and free-growing colonies showed significant variation, with free-standing individuals displaying larger trunk diameters and basal thickness, particularly in the Cinarli and Nara sites.\u003c/p\u003e\u003cp\u003eThe current work also represents the first report of engulfment action encountering from 10 different colonies of \u003cem\u003eParamuricea clavata\u003c/em\u003e in the \u0026Ccedil;anakkale Strait and the Sea of Marmara (Marmara Island). Morphometric details are further summarized in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e.\u003c/p\u003e"},{"header":"Results and Discussion","content":"\u003cp\u003eThis study documents the largest \u003cem\u003eSavalia savaglia\u003c/em\u003e colonies ever recorded in Turkish waters, with some individuals surpassing previous Mediterranean records in both height and basal width. For example, colony heights of up to 133 cm and basal widths exceeding 139 cm were documented measurements that surpass those reported by Gaglioti et al. (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2019\u003c/span\u003e) from Ustica Island. Additionally, trunk diameters exceeded the 14 cm record by Bell (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e1891\u003c/span\u003e), highlighting the exceptional size and potential age of these specimens.\u003c/p\u003e\u003cp\u003eThe remarkable size of these colonies suggests an old age, which is consistent with previous estimates of extremely slow growth rates for \u003cem\u003eSavalia\u003c/em\u003e species. Cerrano et al. (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2010\u003c/span\u003e) and Roark et al. (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2006\u003c/span\u003e) estimated growth rates between 14\u0026ndash;45 \u0026micro;m/year with the skeleton character dating back to 2700 years, while Grigg (2002) reported a colony with a 2.6 m trunk corresponding to approximately 70 years of age. While precise age estimation is beyond the scope of this study, the morphometric parameters reported here provide strong evidence for the long-lived nature of the observed colonies. Morphometric characters of \u003cem\u003eSavalia savaglia\u003c/em\u003e measured at the stations are given Table \u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eMorphometric characters of \u003cem\u003eSavalia savaglia\u003c/em\u003e measured at the stations.\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"5\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCOLONY\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eStation/Depth\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eMaximum\u003c/p\u003e\u003cp\u003eHeight / Width\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eTrunk\u003c/p\u003e\u003cp\u003eDiameter\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eBasal\u003c/p\u003e\u003cp\u003eCircumference\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCST-1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eEceabat/42 m\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e117/104 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e13.2 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e26.4 cm\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCST-2A\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eNara/40 m\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e80.2/70 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e10 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e6 cm\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCST-2B\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eNara/40 m\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e69/12 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e8 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u0026gt;\u0026thinsp;5 cm\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCST-3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eNara/38 m\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e57/18.5 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e6.5 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e7.1 cm\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMar-1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eCinarli/42 m\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e50/96.4 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e16.4 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e22 cm\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMar-2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eCinarli/42 m\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e53/62.8 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e9 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e8.5 cm\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMar-3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eCinarli/41 m\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e62/70.5 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e11.2 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e22 cm\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMar-4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eAOR/44 m\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e62/34 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e6.4 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e4.5 cm\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMar-5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eAOR/37 m\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e18/13 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e5.1 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e9 cm\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMar-6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eHIR/46.8 m\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e49/60 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e10 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e16 cm\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAS-1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eAS/56 m\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e133/139 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u0026gt;\u0026thinsp;18 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u0026gt;\u0026thinsp;20 cm\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"5\"\u003e\u0026Ccedil;ST: \u0026Ccedil;anakkale Strait, Mar: Marmara Island, AS: Aegean Sea, AOR: Avsa offshore region, HIR: Hayirsiz Island CST-2: the damaged separate colonies recorded as in closely associated with each other on the same rock,\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eseparate trunks and branches.\u003c/p\u003e\u003cp\u003eOur findings also highlight notable structural diversity among colonies. Colonies forming their own skeletons exhibited greater thickness and basal spread, whereas those showing engulfment behaviour on \u003cem\u003eParamuricea clavata\u003c/em\u003e had more elongated, narrower profiles. This plasticity in growth forms likely reflects adaptive strategies in response to substrate type, light availability, and competition (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eThe study also reports, for the first time, the co-occurrence of \u003cem\u003ePhoronis australis\u003c/em\u003e and \u003cem\u003eTethya citrina\u003c/em\u003e in the coral facies of the Marmara Sea. These findings expand the known distribution of both species and highlight the role of \u003cem\u003eS. savaglia\u003c/em\u003e colonies as biodiversity hotspots. Notably, \u003cem\u003eP. australis\u003c/em\u003e was observed closely associated with cerianthid-dominated Coralligenous habitats, whilst- \u003cem\u003eT. citrina\u003c/em\u003e was found in calcium carbonate overhangs near \u003cem\u003eS. savaglia\u003c/em\u003e (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003ePhylum: PORIFERA\u003c/p\u003e\u003cp\u003eClass: Demospongiae\u003c/p\u003e\u003cp\u003eOrder: Tethyida\u003c/p\u003e\u003cp\u003eFamily: Tethyidae\u003c/p\u003e\u003cp\u003eSpecies: \u003cem\u003eTethya citrina\u003c/em\u003e Sar\u0026agrave; \u0026amp; Melone, 1965\u003c/p\u003e\u003cp\u003eRemarks: First record from the Sea of Marmara; observed on a calcium carbonate overhang near \u003cem\u003eS. savaglia\u003c/em\u003e colonies.\u003c/p\u003e\u003cp\u003ePhylum: CNIDARIA\u003c/p\u003e\u003cp\u003eClass: Hexacorallia\u003c/p\u003e\u003cp\u003eOrder: Zoantharia\u003c/p\u003e\u003cp\u003eSuborder: Macrocnemina\u003c/p\u003e\u003cp\u003eFamily: Parazoanthidae\u003c/p\u003e\u003cp\u003eSpecies: \u003cem\u003eSavalia savaglia\u003c/em\u003e (Bertoloni, 1819)\u003c/p\u003e\u003cp\u003eRemarks: First confirmed record from the North Aegean coasts of Turkey and new mesophotic reef sites in the Sea of Marmara.\u003c/p\u003e\u003cp\u003ePhylum: PHORONIDA\u003c/p\u003e\u003cp\u003eClass: Phoronata\u003c/p\u003e\u003cp\u003eOrder: Phoronida\u003c/p\u003e\u003cp\u003eFamily: Phoronidae\u003c/p\u003e\u003cp\u003eSpecies: \u003cem\u003ePhoronis australis\u003c/em\u003e Haswell, 1883\u003c/p\u003e\u003cp\u003eRemarks: First record from the Sea of Marmara; found in coralligenous habitats associated with \u003cem\u003eCerianthus membranaceus\u003c/em\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eThe impact of anthropogenic threats on \u003cem\u003eS. savaglia\u003c/em\u003e habitats was also quantified. Out of 186 surveyed coral colonies (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e), 60 were found dead, and six \u003cem\u003eS. savaglia\u003c/em\u003e colonies showed physical damage likely caused by discarded seine nets. In the Avşa Offshore region, 84 dead colonies of \u003cem\u003eParamuricea clavata\u003c/em\u003e were documented, and anchoring activities were observed to cause severe fragmentation. This marks the first evidence of seine net impacts on \u003cem\u003eS. savaglia\u003c/em\u003e in the region (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e), underscoring the urgency of marine conservation actions.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eMarmara Sea (Marmara Island).\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eUltimately, the documentation of novel occurrences in the North Aegean Sea (Turkey), specifically rare morphologies and previously unrecorded species, alongside evidence of habitat degradation attributed to cumulative anthropogenic pressures (e.g., seine fishing, illegal fishing, and anchoring), demonstrates a critical requirement for targeted conservation initiatives. The creation of a coral-focused marine protected area in the Marmara Sea, particularly near Marmara Island, is crucial for the preservation of these unique mesophotic communities, especially when supported by robust regulations targeting destructive practices. Continued long-term monitoring and increased public awareness will be essential in safeguarding this vulnerable ecosystem.\u003c/p\u003e\u003cp\u003eThe findings of this study underscore the ecological importance and conservation urgency of \u003cem\u003eSavalia savaglia\u003c/em\u003e habitats within the Turkish Straits System and adjacent North Aegean Sea. By documenting exceptional colony sizes, rare morphological traits, new species associations, and human-induced damages, this research emphasizes the necessity of immediate conservation action. A coral-specific marine protected area would provide much-needed legal and ecological safeguards for the region\u0026rsquo;s mesophotic biodiversity. Moreover, this study serves as a call for integrated monitoring, stakeholder involvement, and adaptive management practices to ensure the resilience and sustainability of these unique marine ecosystems.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003ch2\u003eSupplementary Material\u003c/h2\u003e\u003cp\u003eSupplementary material includes an underwater video documenting one of the largest observed \u003cem\u003eSavalia savaglia\u003c/em\u003e) and gorgonian forests enhance colonies recorded in the studied regions. This video provides the first visual confirmation of the colony\u0026rsquo;s morphological traits and its associated benthic biodiversity and ecosystem functioning in the Turkish seas.\u003c/p\u003e\u003c/p\u003e\u003ch2\u003eAcknowledgements\u003c/h2\u003e\u003cp\u003eThe authors express their sincere gratitude to Mr. Volkan Artut and Mr. Evren G\u0026ouml;\u0026ccedil;en for his professional diving support during the UNDP Project 2022, and to Mr. \u0026Ouml;mer Altuncu for his assistance as a guide diver. We also thank Mr. A. Hakan Eğilmez, Lecturer and technical diving instructor, and Mr. Barkın İren of the ABZU Technical Diving Team for their valuable contributions and for providing video documentation of a giant \u003cem\u003eSavalia savaglia\u003c/em\u003e colony observed during scientific deep dives in the Babakale region.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eAltuna, A, \u0026amp; Poliseno, A. (2019). Taxonomy, genetics and biodiversity of mediterranean deep-sea corals and cold-water corals. In Orejas C, Jim\u0026eacute;nez C. eds. Mediterranean Cold-Water Corals: Past, Present and Future, Coral Reefs of the World 9. Springer Nature, 14, 121\u0026ndash; 156. doi: 10.1007/978-3-319-91608-8_14\u003c/li\u003e\n\u003cli\u003eBell, F. J. (1891). Contributions of our knowledge of Antipatharian corals. Transactions of the Zoological Society of London, 13 141\u0026ndash;142. \u003c/li\u003e\n\u003cli\u003eCanessa, M., Trainito, E., Bavestrello, G. et al. (2024). A large non-parasitic population of Savalia savaglia (Bertoloni, 1819) in the Boka Kotorska Bay (Montenegro). Sci Rep 14, 7785. https://doi.org/10.1038/s41598-024-58101-y\u003c/li\u003e\n\u003cli\u003eCerrano, C., Danovaro, R., Gambi, C., Pusceddu, A, Riva, A., \u0026amp; Schiaparelli, S. (2010). Gold coral (Savalia savaglia) and gorgonian forests enhance benthic biodiversity and ecosystem functioning in the mesophotic zone. Biodiversity Conservation, 19, 153\u0026ndash;167. doi: 10.1007/s10531-009-9712-5\u003c/li\u003e\n\u003cli\u003eGaglioti, M., Dieli, T., Gambi, M. C., \u0026amp; Cerrano, C. (2019). What am I doing here? An unusual ecological context of a population of Savalia savaglia (Anthozoa) at the Ustica island (Italy). Biologia Marina Mediterranea, 26 (1), 310-311. \u003c/li\u003e\n\u003cli\u003eGiglio, V. J., Ternes, M. L. F., Mendes, T. C., Cordiero, C. A. M. M., \u0026amp; Ferreira, C. E. L. (2017). Anchoring damages to benthic organisms in a subtropical scuba dive hotspot. Journal of Coastal Conservation, 21, 311\u0026ndash;316. doi: 10.1007/s11852-017-0507-7\u003c/li\u003e\n\u003cli\u003eGiusti, M., Cerrano, C., Angiolillo, M., Tunesi, L., \u0026amp; Canese, S. (2015). An updated overview of the geographic and bathymetric distribution of Savalia savaglia. Mediterranean Marine Science, 16, 128\u0026ndash;135. doi: 10.12681/mms890\u003c/li\u003e\n\u003cli\u003eMačić, V., Trainito, E., \u0026amp; Đorđević, N. (2024). Anthozoa of the Adriatic: New insights and a checklist for the southeastern Adriatic. Mediterranean Marine Science, 25 (2), 532-547. doi: 10.12681/mms.36835\u003c/li\u003e\n\u003cli\u003eOca\u0026ntilde;a, O., Brito, A., N\u0026uacute;\u0026ntilde;ez, J., \u0026amp; Bacallado, J. J. (1995). Redescripci\u0026oacute;n de Geradia savaglia (Bertoloni, 1819) (Anthozoa: Zoantharia: Gerardiidae). \u003cem\u003eVieraea\u003c/em\u003e, \u003cem\u003e24\u003c/em\u003e, 153-164\u003c/li\u003e\n\u003cli\u003eOca\u0026ntilde;a, O., \u0026amp; Brito, A. (2004). A review of the Gerardiidae (Anthozoa: Zoantharia) from the Macaronesian Islands and the Mediterranean Sea with the description of a new species. Revista de la Academia Canaria de Ciencias, 15, 159\u0026ndash;189.\u003c/li\u003e\n\u003cli\u003e\u0026Ouml;zalp, H. B. (2021). First massive mucilage event observed in deep waters of \u0026Ccedil;anakkale Strait (Dardanelles), Turkey. Journal of the Black Sea/Mediterranean Environment, 27 (1), 49-66\u003c/li\u003e\n\u003cli\u003e\u0026Ouml;zalp, H. B. (2022). Development, Conservation, Monitoring and Management of Coral Reef Marine Biodiversity Areas in the Turkish coasts. \u0026Ccedil;anakkale Strait, Bozcaada Island, Marmara Island. Action Plan. 62 pp (in Turkish).\u003c/li\u003e\n\u003cli\u003ePulido-Mantas, T., Varotti, C., Roveta, C., Palma, M., Innocenti, C., Giusti, M., Benabdi, M., Trainito, E., Mačić V, Gambi, M. C, \u0026amp; Cerrano, C. (2022). Mediterranean Sea shelters for the gold coral Savalia savaglia (Bertoloni, 1819): An assessment of potential distribution of a rare parasitic species. Marine Environmental Research, 179,105686. doi: 10.1016/j.marenvres.2022.105686 \u003c/li\u003e\n\u003cli\u003eRoark, E. B., Guilderson, T. P., Dunbar, R. B., \u0026amp; Ingram, B. L. (2006). Radiocarbon-based ages and growth rates of Hawaiian deep-sea corals. Marine Ecology Progress Series, 327, 1\u0026ndash;4. doi: 10.3354/meps327001\u003c/li\u003e\n\u003cli\u003eRossi L (1958) Primo rinvenimento di \u003cem\u003eGerardia savaglia\u003c/em\u003e (Bert) (Zoantharia) nei mari italiani (Golfo di Genova). Doriana 2(85): 8 pp\u003c/li\u003e\n\u003cli\u003eVerdura, J., Linares, C., Ballesteros, E.. Coma, R, Uriz, M. J., Bensoussan, N., \u0026amp; Cebrian, E. (2019). Biodiversity loss in a Mediterranean ecosystem due to an extreme warming event unveils the role of an engineering gorgonian species. Scientific Reports, 9, 5911. doi: 10.1038/s41598-019-41929-0\u003c/li\u003e\n\u003cli\u003eYavuz, A. (2022). Ghost nets Marmara Sea. https://www.hurriyetdailynews.com/over-320-000-square-meters-of-ghost-net-collected-from-marmara-sea-179376. Accessed on 12 January, 2025.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Supplementary file 1","content":"\u003cp\u003eSupplementary video, is not available with this version.\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"marine-biodiversity","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"marb","sideBox":"Learn more about [Marine Biodiversity](http://link.springer.com/journal/12526)","snPcode":"12526","submissionUrl":"https://www.editorialmanager.com/marb/default2.aspx","title":"Marine Biodiversity","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-6854315/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6854315/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eTrait-based approaches are widely used in ecology to monitor and understand how communities and ecosystems respond to human-driven environmental impacts. \u003cem\u003eSavalia savaglia\u003c/em\u003e, a rarely encountered parazoanthid coral species, is a key ecosystem engineer in the Mediterranean mesophotic zone. This study presents the first morphologically verified records from the North Aegean Sea coast of Turkey and new habitat data from the Turkish Straits System, including the Sea of Marmara. Field surveys documented four major reef systems with 80 associated benthic invertebrates, two of which are new records for the Marmara Sea. Morphological assessments revealed exceptionally large colonies and previously undocumented cases of parasitic and autonomous growth. Observations also represent the first finding of seine net damage and anchoring threats ever recorded in the Turkish Seas. Our results highlight the urgent need for coral-focused marine protected areas to safeguard biodiversity and mitigate anthropogenic pressures.\u003c/p\u003e","manuscriptTitle":"Functional and conservation relevance of Savalia savaglia in the Turkish Straits System: First record from the North Aegean coasts of Turkey and new mesophotic habitats in the Sea of Marmara","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-08-19 11:34:18","doi":"10.21203/rs.3.rs-6854315/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"reviewerAgreed","content":"","date":"2025-11-18T08:54:37+00:00","index":0,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-08-11T07:37:15+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"Marine Biodiversity","date":"2025-07-28T08:01:06+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-07-28T01:46:57+00:00","index":"","fulltext":""},{"type":"submitted","content":"Marine Biodiversity","date":"2025-07-25T06:53:07+00:00","index":"","fulltext":""},{"type":"decision","content":"Major Revisions Needed","date":"2025-07-17T04:36:21+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"marine-biodiversity","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"marb","sideBox":"Learn more about [Marine Biodiversity](http://link.springer.com/journal/12526)","snPcode":"12526","submissionUrl":"https://www.editorialmanager.com/marb/default2.aspx","title":"Marine Biodiversity","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"fdfddea4-5653-46eb-b033-a7b65adfd8df","owner":[],"postedDate":"August 19th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-02-27T16:22:04+00:00","versionOfRecord":[],"versionCreatedAt":"2025-08-19 11:34:18","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6854315","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6854315","identity":"rs-6854315","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}