Short scientific article UDC 595.3:574.3(262.538) Received: 2006-03-20 PRELIMINARY INVESTIGATIONS ON CRUSTACEANS ASSOCIATED WITH THE MEDITERRANEAN MUSSEL (MYTILUS GALLOPROVINCIALIS LAMARCK, 1819) BEDS IN THE UPPER INFRALITTORAL OF THE BOSPHORUS (TURKEY) Evrim KALKAN Department of Environmental Science, Institute of Environmental Science and Technology, Bo gaziçi University, Hisar Campus, TR-34342 Bebek, Istanbul, Turkey E-mail: evrimkalkan@yahoo.com Selahattin Ünsal KARHAN Department of Marine Biology, Institute of Marine Sciences and Management, Istanbul University, Müjküle Sok., No:1, TR-34470 Vefa, Istanbul, Turkey Erhan MUTLU Institute of Marine Sciences, Middle East Technical University, P.O. Box 28, TR-33731 Erdemli, Mersin, Turkey ABSTRACT Twenty crustacean species associated with the Mediterranean mussel (Mytilus galloprovincialis Lamarck, 1819) beds were recorded in the upper infralittoral zone of the Bosphorus. Two species, Microdeutopus algicola Delia Valle, 1893 and Stenothoe tergestina Nebeski, 1811, were recorded for the first time in this area. Key words: Crustacea, Mytilus galloprovincialis, Bosphorus OSSERVAZIONI PRELIMINARI SU CROSTACEI ASSOCIATI A BANCHI DI MITILO COMUNE (MYTILUS GALLOPROVINCIALIS LAMARCK, 1819) NELL'INFRALITORALE SUPERIORE DEL BOSFORO (TURCHIA) SINTESI Venti specie di crostacei associate a banchi del mitilo comune (Mytilus galloprovincialis Lamarck, 1819) sono state determinate nell'infralitorale superiore del Bosforo. Due specie, Microdeutopus algicola Delia Valle, 1893 e Stenothoe tergestina Nebeski, 1811, vengono segnalate per la prima volta in quest'area. Parole chiave: Crustacea, Mytilus galloprovincialis, Bosforo This article is dedicated to the memory of our professor Erdog an Oku§. INTRODUCTION The Bosphorus is a passage between the Black Sea and the Sea of Marmara and is the northernmost part of the Turkish Straits System, which plays significant roles in the biology of the Mediterranean and the Black Sea basins. The Strait acts as a biological barrier between the Sea of Marmara and the Black Sea, limiting the penetration of given species between both seas. By means of two-layered current regime of the Bosphorus, a number of species penetrate the Black Sea from the Sea of Marmara and vice versa, thus the Strait serves as a biological corridor. The Bosphorus is also an acclimatization zone for the Mediterranean species (Ozturk & Ozturk, 1996). Prior to this study, Heller (1863), Colombo (1885), Ostroumoff (1896), Marion (1898), Devedjian (1926), Demir (1952), Tortonese (1959), Caspers (1968), Topaloglu & Kihara (1993), Balkis & Albayrak (1994) and Uysal et al. (2002) recorded some benthic crustaceans from the Bosphorus. Among them, the work of Topalog lu & Kihara (1993) also considered the crustacean species associated with the mussel beds in a small area of the Bosphorus. The purpose of this study is to determine the crustaceans associated with the Mediterranean mussel beds and to contribute to the recognition of zoobenthic assemblages in the Bosphorus, where the waters of the Mediterranean and the Black Sea mix. MATERIAL AND METHODS Sampling of the crustaceans from mussel beds was carried out in January 2003 at 10 stations located at both coasts of the Bosphorus (Fig. 1). Samples were collected from the upper infralittoral zone at depth range of 0.5-1 m. All benthic organisms of the mussel community were removed from the hard substratum by a spatula and fixed in 4% neutral formalin solution. In addition, some environmental parameters such as salinity, temperature and dissolved oxygen were measured at each sampling station. In the laboratory, the samples were sifted in a 1 mm mesh sieve with fresh water and crustaceans separated from the retained material. Separated specimens were preserved in 70% ethanol. The crustaceans were identified to the species level using stereo and compound microscopes. The specimens were deposited in the first author's personal collection. RESULTS AND DISCUSSION Environmental parameters: There was no significant difference in each variable of surface temperature, dissolved oxygen and salinity among the stations (Dispersion index and %2 test; p <0.05). The mean salinity of the study area was 18.1±0.06 psu, the mean temperature was 6.7±0.19 "C, and the mean dissolved oxygen 7.44 ±0.09 mg l-1 with 95% confidence level. Fig. 1: Location of sampling stations in the Bosphorus. SI. 1: Lokacije vzorčišč v Bosporski ožini. Fauna A total of 20 species representing 19 genera and 5 orders were recorded in the area. The amphipods Microdeutopus algicola Della Valle, 1893 and Stenothoe tergestina Nebeski, 1811 are new records for the Bosphorus (Tab. 1). Applying presence/absence data of the community to the McConnaughey similarity index, two different clusters of the stations were obtained at a truncation level of ^ 60%. Group 1 embraced stations 1, 9, 10, whereas Group 2 included the remaining stations. However, the one-way ANOSIM test shows that there was not a significant dissimilarity between Groups 1 and 2 (p <99). Moreover, the MDS plot confirmed insignificant representation of the stations (stress = 0.115). Before the present study, the only research concerning the macrobenthos associated with the Mediterranean mussel beds in the Bosphorus has been carried out by Tab. 1: List of species found at each station. Tab. 1: Seznam vrst, ugotovljenih na posameznih vzorčiščih. SPECIES STATIONS 1 2 3 4 5 6 7 8 9 10 CIRRIPEDIA Balanus improvisus Darwin, 1854* + + + + + + + + + + DECAPODA Pisidia longimana (Risso, 1816)* - + + + + + - - - + Xantho poressa (Olivi, 1792)* + + - - + - - - - - Pilumnus hirtellus (Linnaeus, 1761) - + + + + + + - - - TANAIDACEA Tanais dulongii (Audouin, 1826) + - - + - - - - + - ISOPODA jaera nordmanni (Rathke, 1837)* - - - - - - - - + + Dynamene bidentatus (Adams, 1800)* - + - + + - + + + - Sphaeroma serratum (Fabricius, 1787) + + + + + + + + + + Idotea balthica (Pallas, 1772) + - + - + - + - + + Synisoma capito (Rathke, 1837)* - - - - - - + + - - AMPHIPODA Caprella liparotensis Haller, 1879* - - - - - - - - + + Ampithoe ramondi Audouin 1826 - - - - + - + - + - Microdeutopus algicola Della Valle, 1893* ' f - - - - - + - - - - Gammarellus angulosus (Rathke, 1843)* - - - - + - - + - - Echinogammarus olivii (Milne-Edwards, 1830)* + - - + + - - - + + Hyale perieri (Lucas, 1849)* + + + + + + + + + + jassa marmorata (Holmes, 1903) - + + + + + + + + + jassa ocia (Bate, 1862)* - + - + - - - + + - Melita palmata (Montagu, 1804) - + + - + + + - - + Stenothoe tergestina Nebeski, 1881 * , f - - - - + - - - + + * New record for the mussel associated crustacean fauna of the Bosphorus. + New record for the Bosphorus. Topalog lu & Kihara (1993). According to these authors, Crustacea is the dominant taxon in the area investigated, where a total of 22 crustacean species have been recorded. The present study has contributed 13 new records (Tab. 1) to the mussel associated crustacean fauna previously examined by Topalog lu & Kihara (1993), and two of them (M. algicola and S. tergestina) are new records for the Bosphorus. As a result, the number of the crustacean species has now been increased to 35. The number of crustacean species associated with the mussel assemblages varies from 8 (Sicily, Italy: D'Anna et al., 1985) to 32 (Izmir Bay, Turkey: Kocata§, 1978) at vari- ous sites in the Mediterranean infralittoral (Chintiroglou et al., 2004). The number of species seems to depend on the specific features of each study area (polluted/non-polluted, midlittoral/infralittoral) (Thiel & Ullrich, 2002; Chintiroglou et al., 2004). The present study can be accepted as an example for a moderately polluted infralit-toral area located between the Mediterranean and the Black Seas. In conclusion, the current status of the species composition of benthic communities existing in the Bosphorus is far from complete and it is obvious that further research will increase this number. PREDHODNE RAZISKAVE RAKOV V HABITATIH UŽITNE KLAPAVICE (MYTILUS GALLOPROVINCIALIS LAMARCK, 1819) V GORNJEM INFRALITORALU BOSPORSKE OŽINE (TURČIJA) Evrim KALKAN Department of Environmental Science, Institute of Environmental Science and Technology, Bo gazigi University, Hisar Campus, TR-34342 Bebek, Istanbul, Turkey E-mail: evrimkalkan@yahoo.com Selahattin Ünsal KARHAN Department of Marine Biology, Institute of Marine Sciences and Management, Istanbul University, Müjküle Sok., No:1, TR-34470 Vefa, Istanbul, Turkey Erhan MUTLU Institute of Marine Sciences, Middle East Technical University, P.O. Box 28, TR-33731 Erdemli, Mersin, Turkey POVZETEK 9 gornjem infralitoralnem pasu Bosporske ožine je bilo zabeleženih 20 vrst rakov, živečih v habitatih užitne klapavice (Mytilus galloprovincialis Lamarck, 1819). Dve izmed vrst, Microdeutopus algicola Della Valle, 1893 in Stenothoe tergestina Nebeski, 1811 sta bili v tem območju ugotovljeni prvič. Ključne besede: Crustacea, Mytilus galloprovincialis, Bospor REFERENCES Balkis, N. & S. Albayrak (1994): Benthic amphipods of the Bosphorus. Proceedings of the XIIth National Biology Congress. 6-7 July 1994, Edirne, Turkey, p. 277-284. (In Turkish) Caspers, H. (1968): La macrofaune benthique du Bosphore et les problème de l'infiltration des éléments méditerranéens dans la mer Noire. Rapp. Comm. Int. Mer Médit., 19, 107-115. Chintiroglou, C-C., P. Damianidis, C. Antoniadou, M. Lantzouni & D. Vafidis (2004): Macrofauna biodiversity of mussel bed assemblages in Thermaikos Gulf (northern Aegean Sea). Helgol. Mar. Res., 58, 62-70. Colombo, A. (1885): Raccolte zoologiche eseguite dal R. Pirascafo Washington nella campagna abissale tallas-sografica dell'anno 1885. Rivista Marittima, p. 22-53. D'Anna, G., G. Giaccone & S. Riggio (1985): Linea-menti bionomici dei banchi di mitili di Balestrate (Sicilia Occidentale). Oebalia, 11, 389-399. Demir, M. (1952): Benthic invertebrates of the coasts of the Bosphorus and the Prince Islands. Publ. Hydrobiol. Res. Inst. Faculty of Science, Istanbul University, Nr. 3, 615 pp. (In Turkish) Devedjian, K. (1926): Pêche et Pécheries en Turquie. Imprimerie de l'Administration de la Dette Publique Ottomane, Istanbul, 459 pp. Heller, C. (1863): Crustaceen des südlichen Europa. Crustacea Podophthalmia. Mit einer Uenersicht über die horizontale Verbreitung sämtlicher europäisher Arten. Wilhelm Braumüller, Wien, 336 pp. Kocatas, A. (1978): Contribution à l'étude des peuplements des horizons supérieurs de substrat rocheux du Golfe D'Izmir (Turquie). Ege Üniversitesi Fen Fakültesi Monografiler Serisi, 12, 1-93. Marion, A. F. (1898): Notes sur la faune des Dardanelles et du Bosphore. Ann. Mus. Hist. Nat. Marseille, 1, 163182. Ostroumoff, A. (1896): Compdes-rendus des dragages et du plancton de l'expédition de "Selianik". Bulletin de l'Académie Impériale des Sciences de St. Petersbourg, 5, 33-92. Öztürk, B. & A. A. Öztürk (1996): On the biology of the Turkish straits system. Bull. Inst. Océanogr., no. spécial 17, 205-221. Thiel, M. & N. Ullrich, (2002): Hard rock versus soft bottom: the fauna associated with intertidal mussel beds on hard bottoms along the cost of Chile, and considerations on the functional role of mussel beds. Helgol. Mar. Res., 56, 21-30. Topalog lu, B. & A. Kihara (1993): Community of Mediterranean mussel Mytilus galloprovincialis Lamarck, 1819 in the Bosphorus Strait. J. Tokyo Univ. Fish., 80, 113-120. Tortonese, E. (1959): Osservazioni sul bentos del Mar di Marmara e del Bosforo. Natura, 50, 18-26. Uysal, A., A. Yüksek, E. Oku§ & N. Yilmaz (2002): Benthic community structure of the Bosphorus and surrounding area. Water Sci. Technol., 46, 37-44.