Anali za istrske in mediteranske študije Annali di Studi istriani e mediterranei Annals for Istrian and Mediterranean Studies Series Historia Naturalis, 34, 2024, 2 UDK 5 Annales, Ser. hist. nat., 34, 2024, 2, pp. 173-358, Koper 2024 ISSN 1408-533X KOPER 2024 Anali za istrske in mediteranske študije Annali di Studi istriani e mediterranei Annals for Istrian and Mediterranean Studies Series Historia Naturalis, 34, 2024, 2 UDK 5 ISSN 1408-533X e-ISSN 2591-1783 ANNALES · Ser. hist. nat. · 34 · 2024 · 2 Anali za istrske in mediteranske študije - Annali di Studi istriani e mediterranei - Annals for Istrian and Mediterranean Studies ISSN 1408-533X UDK 5 Letnik 34, leto 2024, številka 2 e-ISSN 2591-1783 UREDNIŠKI ODBOR/ COMITATO DI REDAZIONE/ BOARD OF EDITORS: Alessandro Acquavita (IT), Nicola Bettoso (IT), Christian Capapé (FR), Darko Darovec, Dušan Devetak, Jakov Dulčić (HR), Serena Fonda Umani (IT), Andrej Gogala, Daniel Golani (IL), Danijel Ivajnšič, Mitja Kaligarič, Marcelo Kovačič (HR), Andrej Kranjc, Lovrenc Lipej, Vesna Mačić (ME), Alenka Malej, Patricija Mozetič, Martina Orlando- Bonaca, Michael Stachowitsch (AT), Tom Turk, Al Vrezec Glavni urednik/Redattore capo/ Editor in chief: Darko Darovec Odgovorni urednik naravoslovja/ Redattore responsabile per le scienze naturali/Natural Science Editor: Lovrenc Lipej Urednica/Redattrice/Editor: Martina Orlando-Bonaca Prevajalci/Traduttori/Translators: Martina Orlando-Bonaca (sl./it.) 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Navodila avtorjem in vse znanstvene revije in članki so brezplačno dostopni na spletni strani https://zdjp.si/en/p/annalesshn/ The submission guidelines and all scientific journals and articles are available free of charge on the website https://zdjp.si/en/p/annalesshn/ Le norme redazionali e tutti le riviste scientifiche e gli articoli sono disponibili gratuitamente sul sito https://zdjp.si/en/p/annalesshn/ ANNALES · Ser. hist. nat. · 34 · 2024 · 2 Anali za istrske in mediteranske študije - Annali di Studi istriani e mediterranei - Annals for Istrian and Mediterranean Studies UDK 5 Letnik 34, Koper 2024, številka 2 ISSN 1408-53 3X e-ISSN 2591-1783 VSEBINA / INDICE GENERALE / CONTENTS BIOTSKA GLOBALIZACIJA GLOBALIZZAZIONE BIOTICA BIOTIC GLOBALIZATION Malek ALI, Aola FANDI & Christian CAPAPÉ The First Mediterranean Record of Red-Toothed Triggerfish Odonus niger (Balistidae) from the Syrian Coast (Eastern Mediterranean Sea) ............... Prvi zapis o pojavljanju rdečezobe balestre Odonus niger (Balistidae) iz sirske obale (vzhodno Sredozemsko morje) Zafer TOSUNOĞLU & Okan AKYOL Occurrence of Pterois miles (Scorpaenidae) in the Mediterranean Sea ....................................... Pojavljanje navadne plamenke Pterois miles (Scorpaenidae) v Sredozemskem morju Izdihar Ali AMMAR New Non-Native and Rare Marine Invertebrates in Syrian Waters .................... Novi primeri o pojavljanju tujerodnih in redkih morskih nevretenčarjev v sirskih vodah Luca CASTRIOTA, Manuela FALAUTANO & Laura SINAPI A New Locality Record for the Range Expanding Fish Seriola fasciata in the Mediterranean ................. Nova lokaliteta pojavljanja vrste Seriola fasciata, ki širi areal v Sredozemskem morju F. Saadet KARAKULAK, Mehmet GÖKOĞLU, Uğur UZER & Hakan KABASAKAL First Record of the Abudefduf cf. saxatilis/vaigiensis/ troschelii Species Complex (Pisces: Pomacentridae) in the Black Sea ........................ Prvi zapis o pojavljanju primerka vrste iz kompleksa Abudefduf cf. saxatilis/vaigiensis/troschelii (Pisces: Pomacentridae) iz Črnega morja SREDOZEMSKE HRUSTANČNICE SQUALI E RAZZE MEDITERRANEE MEDITERRANEAN SHARKS AND RAYS Farid HEMIDA, Christian REYNAUD & Christian CAPAPÉ Occurrence of the Rare Blonde Ray, Raja brachyura (Rajidae), Off the Algerian Coast (Southwestern Mediterranean Sea) ........................ Pojavljanje redke okraste raže, Raja brachyura (Rajidae), ob alžirski obali (jugozahodno Sredozemsko morje) Hakan KABASAKAL, Uğur UZER & F. Saadet KARAKULAK Occurrence of Longnosed Skate, Dipturus oxyrinchus, in the Sea of Marmara ...................................................... Pojavljanje koničaste raže, Dipturus oxyrinchus, v Marmarskem morju Cem ÇEVİK, Gökhan GÖKÇE & Deniz ERGUDEN Capture of a Juvenile Sharpnose Sevengill Shark, Heptranchias perlo (Bonnaterre, 1788), from the Turkish Coast (Eastern Mediterranean Sea) with Updated Records from Mediterranean Waters ............................................ Ulov mladostnega primerka morskega psa sedmeroškrgarja, Heptranchias perlo (Bonnaterre, 1788), iz turških voda (vzhodno Sredozemsko morje) z posodobljenim seznamom zapisov o pojavljanju v Sredozemskem morju 173 179 199 205 221 213 229 187 ANNALES · Ser. hist. nat. · 34 · 2024 · 2 Eloïse DEYSSON, Sarah FOXONET, Etienne RÉGNIER, Chloé MOSNIER, Florane TONDU, Janis BROUTIN-RENAUD Bruno COGNIE, Ales- sandro DE MADDALENA, Hakan KABASAKAL & Nicolas ZIANI Additional Historical Records of Great White Sharks, Carcharodon carcharias, Caught in the Gulf of Lion, Northwestern Mediterranean Sea, Between the 1920s and 1950s ............................... Dodatni zgodovinski zapisi o belih morskih volkih, Carcharodon carcharias, ujetih v zalivu Lyon (severozahodno Sredozemsko morje) v dvajsetih in petdesetih letih Malek ALI, Aola FANDI, Dima GHANEM & Christian CAPAPÉ Capture of a Juvenile Basking Shark, Cetorhinus maximus (Cetorhinidae), Off the Syrian Coast, With Comments on the Occurrence of the Species in the Levant Basin (Eastern Mediterranean Sea) ................................................ Ulov mladostnega primerka morskega psa orjaka, Cetorhinus maximus (Cetorhinidae), ob sirski obali s komentarji o pojavljanju vrste v levantskem bazenu (vzhodno Sredozemsko morje) Hakan KABASAKAL, Uğur UZER & F. Saadet KARAKULAK Impact of Fishing Capacity and Environmental Parameters on Landings of Hexanchus griseus in the Sea of Marmara ............................................ Vpliv ribolovne zmogljivosti in okoljskih parametrov na ulov vrste Hexanchus griseus v Marmarskem morju MORSKA FAVNA FAUNA FAUNA MARINE FAUNA Tea KNAPIČ, Irena FRKOVIČ, Borut MAVRIČ & Lovrenc LIPEJ An Insight into the Heterobranch Fauna of Fiesa (Slovenia, Northern Adriatic Sea) ................... Vpogled v favno polžev zaškrgarjev Fiese (Slovenija, severni Jadran) Francesco TIRALONGO, Alessandro NOTA, Emanuele MANCINI & Luigi MUSCO Wounds Inflicted on Humans by the White Seabream (Diplodus sargus): First Scientific Report of Aggressive Behavior ................................ Rane, ki jih ljudem zadajajo šargi (Diplodus sargus): prvo znanstveno poročilo o agresivnem vedenju ORNITOFAVNA ORNITOFAUNA ORNITHOFAUNA ANDREA DE ANGELIS & MARIO PELLEGRINI Nuovo Sito di Nidificazione di Aquila Reale Aquila chrysaetos nel Subappennino Abruzzese ...... Novo gnezdišče planinskega orla v subapeninskih Abrucih FLORA FLORA FLORA Amelio PEZZETTA & MARCO PAOLUCCI La flora di Taranta Peligna (Abruzzo, Italia) ............. Flora Taranta Peligna (Abruci, Italija) Kazalo k slikam na ovitku .................................... Index to images on the cover ............................... 251 257 239 301 291 275 317 357 357 ANNALES · Ser. hist. nat. · 34 · 2024 · 2 275 received: 2024-16-21 DOI 10.19233/ASHN.2024.32 AN INSIGHT INTO THE HETEROBRANCH FAUNA OF FIESA (SLOVENIA, NORTHERN ADRIATIC SEA) Tea KNAPIČ Slovenian Natural History Museum, Prešernova cesta 20, 1000 Ljubljana, Slovenia Irena FRKOVIČ Jenkova ulica 1, 6000 Koper, Slovenia Borut MAVRIČ Marine Biology Station Piran, National Institute of Biology, Piran, Fornače 41, 6330 Piran, Slovenia Lovrenc LIPEJ Marine Biology Station Piran, National Institute of Biology, Piran, Fornače 41, 6330 Piran, Slovenia FAMNIT, University of Primorska, 6000 Koper, Slovenia ABSTRACT The authors investigated the marine heterobranch fauna (Heterobranchia, Gastropoda) in Fiesa, a tourist destination and one of the most popular diving sites in the Gulf of Trieste (northern Adriatic Sea). Specimens of heterobranchs were collected during sporadic sampling between November 2021 and January 2022. A total of 30 species from 6 higher taxa (Cephalaspidea 1, Aplysiida 1, Umbraculida 1, Sacoglossa 3, Pleuro- branchida 2, Nudibranchia 22) were recorded and identified. Including previously published and recorded data, the total number of species currently known in the study area has increased to 51. Future surveys, involving additional sampling methods and carried out during other seasons of the year, are expected to further increase the number of recorded marine heterobranch species inhabiting the area. Key words: marine heterobranchs, checklist, SCUBA diving, Fiesa, recreational divers UNO SGUARDO ALLA FAUNA DEGLI ETEROBRANCHI DI FIESSO (SLOVENIA, ADRIATICO SETTENTRIONALE) SINTESI Gli autori hanno studiato la fauna marina di eterobranchi (Heterobranchia, Gastropoda) a Fiesso, una de- stinazione turistica e uno dei siti di immersione più popolari del Golfo di Trieste (Adriatico settentrionale). Gli esemplari di eterobranchi sono stati raccolti durante campionamenti sporadici tra novembre 2021 e gennaio 2022. In totale sono state registrate e identificate 30 specie appartenenti a 6 taxa superiori (Cephalaspidea 1, Aplysiida 1, Umbraculida 1, Sacoglossa 3, Pleurobranchida 2, Nudibranchia 22). Includendo i dati pubblicati e registrati in precedenza, il numero totale di specie attualmente conosciute nell’area di studio è salito a 51. Le indagini future, che prevedono ulteriori metodi di campionamento e che saranno condotte in altre stagioni dell’anno, dovrebbero aumentare ulteriormente il numero di specie di eterobranchi marini registrate nell’area. Parole chiave: eterobranchi marini, lista, immersioni, Fiesso, subacquei ricreativi ANNALES · Ser. hist. nat. · 34 · 2024 · 2 276 Tea KNAPIČ et al.,: AN INSIGHT INTO THE HETEROBRANCH FAUNA OF FIESA (SLOVENIA, NORTHERN ADRIATIC SEA), 275–290 INTRODUCTION The first checklist of marine gastropod fauna in the Gulf of Trieste (northern Adriatic Sea) including informa- tion on heterobranchs was published over 120 years ago (Graeffe, 1903). The earliest reports for the Slovenian part of the gulf date to the late 20th century and are based on the works of De Min & Vio (1997). The number of heterobranch species reported at the time was limited, as samples were mainly collected using sedimentary bot- tom sampling gear such as Van Veen and Petersen grabs. Later, a first checklist specifically focused on marine sea slugs was published (Turk, 2000), followed by several other studies aimed at assessing the heterobranch fauna in the area, which resulted in a rapidly increasing num- ber of recorded species (Turk, 2005; Lipej et al., 2008, 2012; Mavrič & Lipej, 2012; Lipej et al., 2014; Zenetos et al., 2016). According to Ciriaco & Poloniato (2016), at least 73 species have been recorded in the Italian part of the Gulf of Trieste, while the Slovenian part has recorded 141 species to date (Lipej et al., 2018). The aim of the present work is to provide the first list of marine heterobranchs for Fiesa, one of the sites in the Gulf of Trieste most frequented by recreational divers. MATERIAL AND METHODS Study area The Slovenian coastline is relatively short, covering only 46 km. Fiesa (45°31’31.0’’ N 13°34’53.9’’ E) is a quiet bay located between Piran and Strunjan (Fig. 1), lined on both sides by the steep walls of a flysch cliff. The sea bed begins with a shallow stony-sandy plain, transitioning at a depth of 4–5 m into a distinct flysch sill, and changing at 8–9 m to a silty sandy bottom interspersed with patches of biogenically hardened sub- strate (Fig. 2). The silty sandy bottom slowly descends to a maximum depth of 18 m, with the precoralligenous type of biogenic formation in this area supporting a wide range of habitat types that play an important role biodiversity. Fig. 1: The studied locality of Fiesa (right above) and its position in the Adriatic Sea (left above) as well as in the Slovenian part of the Adriatic Sea (below), along with the areas to which it was compared: A – waters off the old town of Piran, B – Stjuža lagoon (Strunjan), C – Koper harbour, and D – Nature Monument Debeli rtič (Ankaran). Sl. 1: Raziskovana lokaliteta Fiesa (desno zgoraj) in njena lega v Jadranskem morju (levo zgoraj) in v slovenskem delu Jadranskega morja (spodaj), skupaj z območji, s katerimi je bila primerjana: A – akvatorij ob starem mestnem jedru Pirana, B – laguna Stjuža (Strunjan), C – koprsko pristanišče in D – Naravni spomenik Debeli rtič (Ankaran). ANNALES · Ser. hist. nat. · 34 · 2024 · 2 277 Tea KNAPIČ et al.,: AN INSIGHT INTO THE HETEROBRANCH FAUNA OF FIESA (SLOVENIA, NORTHERN ADRIATIC SEA), 275–290 The present work is based on data collected during 12 recreational scuba diving trips in Fiesa between November 2021 and January 2022. All dives were con- ducted at night, with a maximum depth of 12 m (the boundary between rocky and sandy bottoms), and water temperatures varying from 17°C in November to 8°C in January. Data was collected by documenting the sight- ings of each species and photographing them using an Olympus TG6 underwater camera. Photographs of each sighting were re-examined to confirm identification and make other observations. No attempt was made to preserve collected or sighted specimens. Specimens were identified based on their external morphology as observed in detailed photographs and through comparison with relevant literature (Schmekel & Portmann, 1982; Trainito & Doneddu, 2014; Lipej et al., 2018; Prkič et al., 2018). To determine whether a species could be considered a new record for the study area, the data on heterobranch species reported by Lipej et al. (2018) were consulted. The taxonomy and nomen- clature conform to the World Register of Marine Species - WoRMS (2024). For a detailed survey of heterobranch fauna in the studied area, other available data published in previous studies (Lipej et al., 2008, 2012, 2014, 2018) or obtained through social media were analysed. The number of species recorded in Fiesa was compared with those reported from other areas (Fig. 1), such as the Natural Monument of Debeli rtič (Lipej et al., 2016), the Stjuža lagoon in Strunjan (Lipej et al., 2019), the area of the Port of Koper (Lipej et al., 2020), and the waters off the old town of Piran (Lipej et al., 2022). RESULTS AND DISCUSSION Heterobranch fauna A total of 30 heterobranch species from six higher taxonomic groups (Cephalaspidea 1, Aplysiida 1, Umbraculida 1, Sacoglossa 3, Pleurobranchida 2, Nudi- branchia 22) were recorded and identified in this study, six of which are new records for Fiesa: Eubranchus viriola (Korshunova, Malmberg, Prkić, Petani, Fletcher, Lundin & Martynov, 2020), Idaliadoris depressa (Alder & Hancock, 1842), Berthella plumula (Montagu, 1803), Fig 2: Cross-section of the main habitats present in the studied area across the depth range. Sl. 2: Prečni prerez glavnih habitatov, prisotnih na proučevanem območju v globinskem razponu. ANNALES · Ser. hist. nat. · 34 · 2024 · 2 278 Tea KNAPIČ et al.,: AN INSIGHT INTO THE HETEROBRANCH FAUNA OF FIESA (SLOVENIA, NORTHERN ADRIATIC SEA), 275–290 Discodoris rosi Ortea, 1979, and Philinopsis depicta (Renier, 1807) (Tab. 1). The 31 heterobranch species recorded are presented in Figures 3 and 4. The most notable new addition to the Fiesa het- erobranch checklist may be Eubranchus viriola, which was described only recently, in 2020 (Korshunova et al., 2020). Specimens were mainly translucent white; however, some brown specimens were also observed, distinguished from the similar species Amphorina farrani (Alder & Hancock, 1842) by the absence of a yellow-or- ange spot on the tail. During sampling, some specimens matching the description of the recently discovered species Amphorina viriola were found (Korshunova et al., 2020). However, due to recent doubts regarding the distinction between similar species of the genus Amphorina and the validity of this genus, along with the Tab. 1: Heterobranch species recorded in the study area in the period November 2021–January 2022. The plus signs denote an estimate of heterobranch abundance. Tab. 1: Zabeležene vrste polžev zaškrgarjev na obravnavanem območju v obdobju november 2021–januar 2022. Znaki plus označujejo oceno številčnosti polžev zaškrgarjev. date/ species 2021 2022 21 nov 27 nov 29 nov 4 dec 5 dec 12 dec 15 dec 26 dec 29 dec 9 jan 15 jan 22 jan 30 jan 1 Antiopella cristata           1               2 Amphorina linensis             1             3 Aplysia punctata     1         2       3 5 4 Berthella ocellata                   1       5 Berthella plumula         1                 6 Cratena peregrina     5   3 2 2   1         7 Dendrodoris grandiflora             1     1   4 1 8 Dendrodoris limbata   1       1 1 1     2 2 3 9 Discodoris rosi                 1 1       10 Doris pseudoargus 1     2   2 4             11 Doris sp.         1         1       12 Elysia gordanae                     1 1 1 13 Elysia timida         1     1           14 Elysia viridis             5+ 5+   5+ 10+ 10+ 10+ 15 Facelina fusca     5+ 5+ 5+ 5+ 5+ 10+ 5+     10+ 10+ 16 Eubranchus viriola             5   2         17 Felimare picta 3 2 1   5+ 1 2 1     1 1 1 18 Felimare villafranca 1   2 1   4 1 1         1 19 Felimida krohni                         1 20 Felimida luteorosea 1                         21 Geitodoris planata                       1   22 Idaliadoris depressa                         2 23 Paraflabellina ischitana         1                 24 Philinopsis depicta   1                       25 Polycera quadrilineata       1     1       1     26 Spurilla neapolitana           1     1         27 Thuridilla hopei         1                 28 Trapania maculata                   1       29 Trapania lineata                   1       ANNALES · Ser. hist. nat. · 34 · 2024 · 2 279 Tea KNAPIČ et al.,: AN INSIGHT INTO THE HETEROBRANCH FAUNA OF FIESA (SLOVENIA, NORTHERN ADRIATIC SEA), 275–290 Fig. 3: Heterobranch species recorded in the study area. A – Philinopsis depicta, B – Boselia mimetica, C – Elysia timida, D – Elysia viridis, E – Elysia gordanae, F – Thuridilla hopei, G – Ercolania viridis, H – Placida cremoniana, I – Aplysia punctata, J – a small specimen of Aplysia punctata (formerly Aplysia parvula), K – Tylodina perversa, L – Berthella ocellata, M – Berthella plumula, N – Berthellina edwardsi, O – Trapania lineata, and P – Trapania maculata (Photos: Tea Knapič: A, C, D, F, K, L, M, O, P; Irena Frkovič: J; Borut Mavrič: B, E, G, H, I, N). SL. 3: Favna polžev zaškrgarjev na obravnavanem območju. A – Philinopsis depicta, B – Boselia mimetica, C – Elysia timida, D – Elysia viridis, E – Elysia gordanae, F – Thuridilla hopei, G – Ercolania viridis, H – Placida cremoniana, I – Aplysia punctata, J – majhen primerek vrste Aplysia punctata (prej Aplysia parvula), K – Tylodina perversa, L – Berthella ocellata, M – Berthella plumula, N – Berthellina edwardsi, O – Trapania lineata, in P – Trapania maculata (Fotografije: Tea Knapič: A, C, D, F, K, L, M, O, P; Irena Frkovič: J; Borut Mavrič: B, E, G, H, I, N). ANNALES · Ser. hist. nat. · 34 · 2024 · 2 280 Tea KNAPIČ et al.,: AN INSIGHT INTO THE HETEROBRANCH FAUNA OF FIESA (SLOVENIA, NORTHERN ADRIATIC SEA), 275–290 Fig. 4: Heterobranch species recorded in the study area. A – Dendrodoris limbata, B – Doris cf. pseudoargus, C – Rostanga rubra, D – Discodoris rosi, E – Antiopella cristata, F – Diaphorodoris alba, G – Felimida luteorosa, H – Felimida krohni, I – Felimare picta, J – Felimare villafranca, K – Felimare orsinii, L – Polycera quadriline- ata, M – Facelina fusca, N – Paraflabellina ischitana, O – Spurilla neapolitana, and P – Eubranchus viriola (Photos: Tea Knapič: A, B, D, E, G, H, I, J, K, L, M, N, O, P; Tihomir Makovec: C; Domen Trkov: F). Sl. 4: Favna polžev zaškrgarjev na obravnavanem območju. A – Dendrodoris limbata, B – Doris cf. pseudoargus, C – Rostanga rubra, D – Discodoris rosi, E – Antiopella cristata, F – Diaphorodoris alba, G – Felimida luteorosa, H – Felimida krohni, I – Felimare picta, J – Felimare villafranca, K – Felimare orsinii, L – Polycera quadriline- ata, M – Facelina fusca, N – Paraflabellina ischitana, O – Spurilla neapolitana, in P – Eubranchus viriola (Fotografije: Tea Knapič: A, B, D, E, G, H, I, J, K, L, M, N, O, P; Tihomir Makovec: C; Domen Trkov: F). ANNALES · Ser. hist. nat. · 34 · 2024 · 2 281 Tea KNAPIČ et al.,: AN INSIGHT INTO THE HETEROBRANCH FAUNA OF FIESA (SLOVENIA, NORTHERN ADRIATIC SEA), 275–290 lack of a comprehensive review of the genus  Eubran- chus, we prefer to use the Latin name Eubranchus viriola (see Toso et al., 2024). Checklist of species Counting the species observed in the studied area, alongside those reported in previous publications (Li- pej et al., 2008, 2012, 2014, 2018) (Tab. 2), the total number of heterobranch species registered in the Fiesa area to date is 51. The discovery of 30 species over three months and a comprehensive checklist of 51 document- ed species indicate Fiesa to be a species-rich area. If we compare the number of heterobranch species recorded for Fiesa with the previously reported survey of species in Slovenian waters (141 species) compiled by Lipej et al. (2018), it accounts for over 1/3 of all species ever reported in these waters. However, since many common sea slug species present in neighbouring areas were not confirmed in this study, it may be speculated that the 51 species recorded so far are an underestimation of the true number of heterobranch species in the study area. Such heterobranch diversity can be attributed to the high spatial heterogeneity and the variety of habitat types present in the studied area. It is well known that the abundance and distribution patterns of benthic biodiversity are influenced by spatial het- erogeneity (Zuschin et al., 2001; Bouchet et al., 2002; Romoth et al., 2023). Many heterobranch species are characterized by vivid coloration, but as typically small animals that only occur in low densities and in specific habitats (Zenetos et al., 2016), they may not be easily spotted. Some cryptic species, such as those from the family Onchidorididae. were often overlooked in the past due to their excellent camouflage. An onchidorid species, Atalodoris pictoni (Furfaro & Trainito, 2017) (Fig. 5), which feeds on the encrusting bryozoan Reptadeonella violacea (Johnston, 1847), was previously reported in the area by Fortič et al. (2021). A new species, Atal- odoris camassae (Furfaro & Trainito, 2022) (Fig. 6), was recently described from the studied area by Furfaro et al. (2023). It was observed feeding on the cheilostoma- tid bryozoan Calpensia nobilis (Esper, 1796). Tab. 2: Heterobranch species previously recorded in the studied area (with date of first record) according to published papers (pp) and social media (sm). Tab. 2: Vrste polžev zaškrgarjev, predhodno zabeležene na obravnavanem proučevanem območju (z datumom prvega zapisa o pojavljanju) glede na objavljene članke (pp) in družbena omrežja (sm).   date/ species source date of first record type 1 Armina rubida Knapič et al. (2024) 10.10.2023 pp 2 Atalodoris camassae Furfaro et al. (2023) March 2021 pp 3 Atalodoris pictoni Fortič et al. (2021) 20.07.2021 pp 4 Baptodoris cinnabarina Frković (2022) 13.02.2021 sm 5 Berghia coerulescens Knapič (2023) 20.08.2023 sm 6 Berthellina edwardsi Novak Srke (2023) 1.01.2023 sm 7 Bosellia mimetica Lipej et al. (2018) 24.09.2014 pp 8 Bursatella leachi Lipej et al. (2018) 19.10.2014 pp 9 Diaphorodoris alba Trkov & Lipej (2022) 12.07.2021 pp 10 Doris ocelligera Lipej et al. (2018) 12.01.2017 pp 11 Ercolanea coerulea Lipej et al. (2018) 24.09.2014 pp 12 Ercolanea viridis Lipej et al. (2018) 24.09.2014 pp 13 Favorinus branchialis Lipej et al. (2018) 24.09.2014 pp 14 Felimare orsinii Lipej et al. (2018) 10.06.2011 pp 15 Jorunna tomentosa Lipej et al. (2018) 27.03.2011 pp 16 Placida cremoniana Lipej et al. (2018) 11.09.2016 pp 17 Placida dendritica Lipej et al. (2018) 24.09.2014 pp 18 Rostanga rubra Lipej et al. (2018) 27.03.2011 pp 19 Tayuva iliacina Lipej et al. (2018) 12.01.2017 pp 20 Tethys fimbria Godnič (2023) 3.06.2023 sm 21 Trinchesia genovae Lipej et al. (2018) 24.09.2014 pp ANNALES · Ser. hist. nat. · 34 · 2024 · 2 282 Tea KNAPIČ et al.,: AN INSIGHT INTO THE HETEROBRANCH FAUNA OF FIESA (SLOVENIA, NORTHERN ADRIATIC SEA), 275–290 Fig. 5: Atalodoris pictoni, a recently discovered, lesser-known nudibranch from the area of Fiesa (Photo: M. Fantin). Sl. 5: Atalodoris pictoni, nedavno odkrita, manj znana vrsta gološkrgarja iz okolice Fiese (Foto: M. Fantin). Fig. 6: Atalodoris camassae, a recently discovered heterobranch species, described as new species with the locus typicus in Fiesa (Photo: I. Frkovič). Sl. 6: Atalodoris camassae, nedavno odkrita vrsta polža zaškrgarja, opisana kot nova vrsta z locus typicus v Fiesi. (Foto: I. Frkovič). ANNALES · Ser. hist. nat. · 34 · 2024 · 2 283 Tea KNAPIČ et al.,: AN INSIGHT INTO THE HETEROBRANCH FAUNA OF FIESA (SLOVENIA, NORTHERN ADRIATIC SEA), 275–290 Among the 51 species of heterobranchs recorded in the Fiesa area, two are non-indigenous: Bursatella leachi Blainville, 1817 and Armina rubida (A. Gould, 1852). The former has regularly occurred in Slovenian waters since 2007 (see Lipej et al., 2018), while A. rubida (Fig. 7) was only recently discovered on the sedimentary bottom in Fiesa (Knapič et al., 2024). It was found on a bare muddy bottom during a night dive. However, after being spotted and illuminated by a torch, it immediately began burrowing into the mud. This finding was the sec- ond record of the species in the Adriatic Sea (Knapič et al., 2024) and the first sighting in the northern Adriatic. We also found a specimen that matched the character- istics of the former Aplysia parvula Mörch, 1863 (Fig. 3J); however, based on new discoveries, Mediterranean specimens previously identified as this species are now considered to be small specimens of Aplysia punctata (Cuvier, 1803) (sensu Golestani et al., 2019). The list of species inhabiting the Fiesa area is far from complete. As heterobranchs are known to be stenopha- gous, specialising in specific diets of algae, cnidarians, sponges, and bryozoans (McDonald & Nybakken, 1997; Furfaro et al., 2017), surveys targeting specific prey species may help record some previously overlooked heterobranch in the future. While most data on hetero- branchs originate from summer sampling (Zenetos et al., 2016), our study, in contrast, highlights heterobranch fauna during the coldest period of the year. Comparison with adjacent areas When comparing the data on heterobranch species in Fiesa with those from other areas in the Slovenian part of the Adriatic Sea where lists of marine fauna and flora have been compiled (Tab. 3), Fiesa emerges as a heterobranch hotspot, with the highest number of Fig. 7: Armina rubida, an alien heterobranch species, recently discovered in the studied area (Photo: T. Knapič). Sl. 7: Na proučevanem območju nedavno odkrita tujerodna vrsta polža zaškrgarja Armina rubida (Foto: T. Knapič). ANNALES · Ser. hist. nat. · 34 · 2024 · 2 284 Tea KNAPIČ et al.,: AN INSIGHT INTO THE HETEROBRANCH FAUNA OF FIESA (SLOVENIA, NORTHERN ADRIATIC SEA), 275–290 Tab. 3: Updated list of Heterobranchia species identified in Fiesa compared to heterobranch fauna from other areas of the Slovenian part of the Adriatic Sea. Tab. 3: Posodobljen seznam vrst polžev zaškrgarjev, ugotovljenih v Fiesi, v primerjavi s favno zaškrgarjev iz drugih območij slovenskega dela Jadranskega morja.     FIESA Nature Monument DEBELI RTIČ Stjuža lagoon STRUNJAN Port of Koper, KOPER waters off the old city, PIRAN "n" heterobranch species THIS WORK Lipej et al. (2016) Lipej et al. (2019) Lipej et al. (2020) Lipej et al. (2022) 1 Acteon tornatilis   X   X   2 Aegires pallensis         X 3 Akera bullata   X X X   4 Amphorina linensis X         5 Antiopella cristata X X     X 6 Aplysia punctata X   X     7 Atalodoris camassae X         8 Atalodoris pictoni X         9 Baptodoris cinnabarina X       X 10 Berghia coerulescens X X     X 11 Berghia verrucicornis     X     12 Berthella ocellata X       X 13 Berthella plumula X         14 Berthellina edwardsi X         15 Bosellia mimetica X       X 16 Bursatella leachi X   X X X 17 Calliopaea bellula         X 18 Calmella cavolini     X     19 Capellinia doriae     X     20 Catriona gymnota     X     21 Cratena peregrina X X X X X 22 Cylichna cylindracea     X X   23 Dendrodoris grandiflora X X       24 Dendrodoris limbata X   X   X 25 Armina rubida X         26 Diaphorodoris alba X         ANNALES · Ser. hist. nat. · 34 · 2024 · 2 285 Tea KNAPIČ et al.,: AN INSIGHT INTO THE HETEROBRANCH FAUNA OF FIESA (SLOVENIA, NORTHERN ADRIATIC SEA), 275–290 27 Discodoris rosi X         28 Doris bertholotti         X 29 Doris ocelligera X       X 30 Doris pseudoargus X       X 31 Doris sp. X         32 Doto acuta     X     33 Doto coronata     X X   34 Doto cervicenigra     X X X 35 Doto rosea     X X   36 Edmundsella pedata         X 37 Elysia gordanae X       X 38 Elysia timida X X     X 39 Elysia viridis X X X   X 40 Ercolanea coerulea X         41 Ercolanea viridis X   X     42 Eubranchus viriola X   X     434 Eubranchus exiguus     X   X 44 Facelina dubia     X     45 Facelina fusca X X     X 46 Favorinus branchialis X   X   X 47 Felimare orsinii X         48 Felimare picta X         49 Felimare villafranca X X     X 50 Felimida krohni X X     X 51 Felimida purpurea   X       52 Felimida luteorosea X X       53 Geitodoris planata X         54 Haminea fusari         X 55 Haminea hydatis   X       56 Haminea navicula   X       57 Haloa japonica     X     58 Hancockia uncinata     X     ANNALES · Ser. hist. nat. · 34 · 2024 · 2 286 Tea KNAPIČ et al.,: AN INSIGHT INTO THE HETEROBRANCH FAUNA OF FIESA (SLOVENIA, NORTHERN ADRIATIC SEA), 275–290 59 Idaliadoris depressa X         60 Idaliadoris neapolitana       X   61 Jorunna tomentosa X   X     62 Paraflabellina ischitana X X     X 63 Petalifera petalifera   X       64 Philine quadripartita   X       65 Philinopsis depicta X X       66 Piseinotecus sphaerifera       X   67 Placida cremoniana X         68 Placida dendritica X         69 Pleurehdera stellata X X X X 70 Polycera quadrilineata X   X   X 71 Polycera hedgpethi     X   X 72 Polycerella emmertoni     X   X 73 Retusa mammillata   X       74 Retusa truncatula           75 Rostanga rubra X         76 Runcina adriatica         X 77 Runcina ferruginea         X 78 Spurilla neapolitana X X X     79 Stiliger fuscovittatus     X     80 Tayuva iliacina X       X 81 Tergipes tergipes     X     82 Tethys fimbria X         83 Thuridilla hopei X X     X 84 Trapania lineata X         85 Trapania maculata X X       86 Trinchesia genovae X   X   X 87 Tylodina perversa X         88 Weinkauffia turgidula         X   Number of species 51 24 31 11 34 ANNALES · Ser. hist. nat. · 34 · 2024 · 2 287 Tea KNAPIČ et al.,: AN INSIGHT INTO THE HETEROBRANCH FAUNA OF FIESA (SLOVENIA, NORTHERN ADRIATIC SEA), 275–290 observed species and 19 heterobranch species record- ed exclusively in this area. The current checklist of heterobranchs from Fiesa could serve as a baseline for future monitoring of this area, which is currently subject to intense recreational diving tourism. Future surveys, especially during other seasons, are necessary to gather more information about the presence and seasonality of marine heterobranch fauna. ACKNOWLEDGEMENTS We would like to acknowledge all recreational divers who share with us their experiences in finding heterobranchs in the area of Fiesa and to provide us with some important data, which improve the quality of the obtained results. Special thanks to Marco Fantin for the photo of Atalodoris pictoni. ANNALES · Ser. hist. nat. · 34 · 2024 · 2 288 Tea KNAPIČ et al.,: AN INSIGHT INTO THE HETEROBRANCH FAUNA OF FIESA (SLOVENIA, NORTHERN ADRIATIC SEA), 275–290 VPOGLED V FAVNO POLŽEV ZAŠKRGARJEV FIESE (SLOVENIJA, SEVERNI JADRAN) Tea KNAPIČ Slovenian Natural History Museum, Prešernova cesta 20, 1000 Ljubljana, Slovenia Irena FRKOVIČ Jenkova ulica 1, 6000 Koper, Slovenia Borut MAVRIČ Marine Biology Station Piran, National Institute of Biology, Piran, Fornače 41, 6330 Piran, Slovenia Lovrenc LIPEJ Marine Biology Station Piran, National Institute of Biology, Piran, Fornače 41, 6330 Piran, Slovenia FAMNIT, University of Primorska, 6000 Koper, Slovenia POVZETEK Avtorji so raziskovali favno morskih polžev zaškrgarjev (Heterobranchia, Gastropoda) v Fiesi, turistični desti- naciji in enem najbolj priljubljenih potapljaških krajev v Tržaškem zalivu (severni Jadran). Primerke zaškrgarjev so popisovali med novembrom 2021 in januarjem 2022. Popisali in določili so skupno 30 vrst iz 6 višjih taksonov (Cephalaspidea 1, Aplysiida 1, Umbraculida 1, Sacoglossa 3, Pleurobranchida 2, Nudibranchia 22). Vključno s predhodno objavljenimi in zabeleženimi podatki se je skupno število trenutno znanih vrst na območju raziskave povečalo na 51. Smiselno je pričakovati, da bodo prihodnje raziskave, ki bodo vključevale dodatne metode vzor- čenja in bodo izvedene v drugih letnih časih, še povečale število zabeleženih morskih vrst polžev zaškrgarjev, ki naseljujejo to območje. Ključne besede: morski polži zaškrgarji, seznam vrst, potapljanje z avtonomno potapljaško opremo, Fiesa, rekreativni potapljači ANNALES · Ser. hist. nat. · 34 · 2024 · 2 289 Tea KNAPIČ et al.,: AN INSIGHT INTO THE HETEROBRANCH FAUNA OF FIESA (SLOVENIA, NORTHERN ADRIATIC SEA), 275–290 REFERENCES Bouchet, P., P. Lozouet, P. Maestrati & V. 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