Obelia dichotoma Linnaeus 1758

• Main Authors: Gravili, Cinzia, Vito, Doris De, Camillo, Cristina Gioia Di, Martell, Luis, Piraino, Stefano, Boero, Ferdinando
• Format: Text
• Language: unknown
• Published: Zenodo 2015
• Subjects: Biodiversity; Taxonomy; Animalia; Cnidaria; Hydrozoa; Leptothecata; Campanulariidae; Obelia; Obelia dichotoma; Greenland; Indian; Blanco; Gonzalez; Medusa; Genova; Torre; Lopez; Bianchi; Pena; Roca; Gronland; Promontorio; Vito; Posti; Ergen; Iceland
• Online Access: https://dx.doi.org/10.5281/zenodo.6107209; https://zenodo.org/record/6107209

Obelia dichotoma (Linnaeus, 1758) Fig. 108 A–D See Peña Cantero & García Carrascosa (2002) for a complete synonymy. Material examined. HCUS-S 115 p and HCUS-S 115m (Hydrozoa Collection, University of Salento—fauna of the Salento Peninsula)—polyp and medusa stages. Description (based on our own observations; Stechow 1919; Ramil & Vervoort 1992; Cornelius 1995): Hydroid. Hydrorhiza as creeping stolon system; colonies erect, very varied in size and shape; hydrocauli monosiphonic, up to 35 cm high, branched, flexuose to straight, thickened in old colonies, internodes with several annuli at their base, perisarc of older tubes usually conspicuously darker than those of younger tubes; hydrothecae bell-shaped, usually not very deep, thin walled, borne alternately and laterally on completely annulated pedicels at the upper part of the internodes, rim even to crenate, slightly flaring, diaphragm transverse to oblique. Colours: in preserved specimens horn-coloured to dark red-brown; perisarc of older tubes usually conspicuously darker than those of younger tubes. Gonothecae usually inverted-conical on annulated pedicels, truncated at the distal end, mature ones with a short distal neck. Habitat type. Eurybathic species that in the Mediterranean has been found from the tidal level to about 200 m depth (García Carrascosa 1981; Boero & Fresi 1986; Ramil & Vervoort 1992). Hydroid stage recorded in water from normal salinity down to 12 ‰ (Cornelius 1995). Substrate. Epibiontic on other hydroids, Pecten , algae, mussels, bryozoans, ascidians, barnacles, phanerogams, Crustacea, gorgonaceans, worm-tubes, sponge, rock and on recuperated instruments. Seasonality. Present all the year (Boero & Fresi 1986; Llobet et al. 1991; De Vito 2006; Puce et al. 2009; this study) in several localities of the Mediterranean Sea. Reproductive period. January and February (Broch 1933; Boero & Fresi 1986; Gili 1986; Puce et al. 2009), March (Boero & Fresi 1986; Gili 1986; Puce et al. 2009), April (Stechow 1919; Broch 1933; Boero & Fresi 1986; Gili 1986; Puce et al. 2009), May (Boero & Fresi 1986; Puce et al. 2009), June (Broch 1933; Puce et al. 2009), July (Broch 1933; Peña Cantero & García Carrascosa 2002), September (Broch 1933; Morri & Bianchi 1999; Puce et al. 2009), November (Broch 1933; Boero & Fresi 1986; Denitto 1996), December (Broch 1933; Boero & Fresi 1986; Gili 1986; Denitto 1996; Puce et al. 2009), and January–August (De Vito 2006; this study) in the Mediterranean Sea. Medusa. Umbrella circular, flat, 2.5– 6 mm wide, mesoglea very thin; without gastric peduncle; mouth with 4 simple lips; 4 radial canals; gonads spherical to ovoid, sac-like, hanging from middle to end of the radial canals; numerous short, chordal, not extensile marginal tentacles with short endodermal roots extending into bell mesoglea; 8 statocysts situated on underside of basal bulbs of some marginal tentacles. Cnidome. b-mastigophores 2 types (polyp); isorhiza haploneme, the ‘I D -' and ‘I d ’ types (medusa). Distribution. Cosmopolitan (Ramil & Vervoort 1992; Medel & López-González 1996; Schuchert 2001 a; Peña Cantero & García Carrascosa 2002; Bouillon et al. 2004; Gravili et al . 2008 a). Records in Salento. Common at: Marina di Corsano, Torre Vado, Ponte del Ciolo (Presicce 1991); Gulf of Taranto, Brindisi (Denitto 1996; Miglietta et al. 2000); Otranto (Denitto 1996; Miglietta et al . 2000; Fraschetti et al . 2002; De Vito 2006; Gravili 2006; Gravili et al . 2008 a; this study); La Strea, Porto Cesareo (Faucci & Boero 2000); Costa Merlata (Fraschetti et al . 2002; Andreano 2007); Other Apulian records: Gargano (Fraschetti et al . 2002). Remarks. The whole cycle was examined in the present study. O. dichotoma is among the most phenotypically varied of all hydroids; however one of the nematocyst types is diagnostic of the species, which is especially useful in distinguishing it from the somewhat similar O. longissima (for details see Östman 1982, 1987, 1999; Cornelius 1995). The medusae of Obelia are not distinguishable at the species level, whereas they are very distinct from all other hydromedusae (Boero et al. 1996). Boero et. al. (2007) showed that the medusae of O. dichotoma are active filter feeders of microbes. References. Cavolini (1785), Schneider (1898) as Campanularia plicata , Babic (1910, 1913b), Broch (1912, 1933), Stechow (1919), Vatova (1928), Leloup (1934), Billard (1936), Picard (1951 a, 1952, 1958 a), Riedl (1959, 1966), Rossi (1961, 1971), Fey (1970), Schmidt (1973), Chimenz Gusso & Rivosecchi Taramelli (1975), Relini & Romairone (1976), Montanari & Morri (1977), Repetto et al. (1977), Morri (1979 b, 1980 b, 1981 a, b,c, 1985), Boero (1981 a, b), García Carrascosa (1981), Morri & Martini (1981), Morri & Bianchi (1982, 1983, 1999), Boero et al. (1985), Isasi (1985), Boero & Fresi (1986), Llobet et al. (1986, 1991), Roca (1986), García-Rubies (1987), Llobet i Nidal (1987), Ramil (1988), Morri et al. (1991), Bianchi et al. (1993 b), Boero & Fresi (1986), Ramil & Vervoort (1992), Vervoort (1993), Medel & López-González (1996), Migotto (1996), Morri & Bianchi (1999), Piraino et al. (1999), Faucci & Boero (2000), Medel & Vervoort (2000), Miglietta et al. (2000); Schuchert (2001 a), Fraschetti et al. (2002), Peña Cantero & García Carrascosa (2002), Bouillon et al. (2004), De Vito (2006), Gravili (2006), Cinar et al. (2008), Gravili et al . (2008 a), Morri et al. (2009), Puce et al. (2009), Bianchi et al. (2011). : Published as part of Gravili, Cinzia, Vito, Doris De, Camillo, Cristina Gioia Di, Martell, Luis, Piraino, Stefano & Boero, Ferdinando, 2015, The non-Siphonophoran Hydrozoa (Cnidaria) of Salento, Italy with notes on their life-cycles: an illustrated guide, pp. 1-187 in Zootaxa 3908 (1) on pages 152-154, DOI: 10.11646/zootaxa.3908.1.1, http://zenodo.org/record/242729 : {"references": ["Pena Cantero, A. L. & Garcia Carrascosa, A. M. (2002) The benthic hydroid fauna of the Chafarinas Islands (Alboran Sea, western Mediterranean). Zoologische Verhandelingen Leiden, 337, 1 - 180.", "Stechow, E. (1919) Zur Kenntnis der Hydroidenfauna des Mittelmeeres, Amerikas und anderer Gebiete, nebst Angaben uber einige Kirchenpauersche Typen von Plumulariden. Zoologische Jahrbucher, Abeilung fur Systematik, 42 (1), 1 - 172.", "Cornelius, P. F. S. (1995) NorthWest European Thecate Hydroids and their Medusae. Synopses of the British Fauna, New Series, pt. 1 & 2, 1 - 347 & 1 - 386.", "Garcia-Carrascosa, A. M. (1981) Hidrozoos tecados (Hydrozoa Calyptoblastea) del litoral mediterraneo espanol: faunistica, ecologia, bionomia bentonica y biogeografia. Tesis Doctoral Universidad Valencia, 464 pp.", "Boero, F. & Fresi, E. (1986) Zonation and evolution of a Rocky bottom hydroid community. Marine Ecology, 7 (2), 123 - 150. http: // dx. doi. org / 10.1111 / j. 1439 - 0485.1986. tb 00152. x", "Llobet, I., Gili, J. M. & Hughes, R. G. (1991) Horizontal, vertical and seasonal distributions of epiphytic Hydrozoa on the alga Halimeda tuna in the northwestern Mediterranean Sea. Marine Biology Berlin, 110 (1), 151 - 159. http: // dx. doi. org / 10.1007 / bf 01313102", "Broch, H. (1933) Zur kenntnis der Adriatischen fauna Von Split. Skrifter Norske Videnskaps-Akademi i Oslo. Matematisknaturvidenskapelig klasse, 4, 1 - 115.", "Denitto, F. (1996) Etologia alimentare e cicli vitali di alcune specie di Hydroidomedusae: Anthomedusae / Filifera e Leptomedusae (Hydrozoa). Degree Thesis, Biology, Universita degli Studi di Lecce, 176 pp.", "Medel, M. D. & Lopez-Gonzalez, P. J. (1996) Updated catalogue of the Hydrozoans from the Iberian Peninsula and Balearic Islands with remarks on zoogeography and affinities. Scientia Marina, 60 (1), 183 - 209.", "Schuchert, P. (2001 a) Hydroids of Greenland and Iceland (Cnidaria, Hydrozoa). Meddelelser om Gronland, Bioscience, 53, 1 - 184.", "Gravili, C., Boero, F. & Licandro, P. (2008 a) Hydrozoa. Biologia Marina Mediterranea, 15 (Supplement), 71 - 91.", "Presicce, M. M. (1991) Gli idroidi (Cnidaria: Hydrozoa) del litorale salentino. Degree Thesis, Marine Biology, Universita degli Studi di Lecce, 143 pp.", "Miglietta, M. P., Della Tommasa, L., Denitto, F., Gravili, C., Pagliara, P., Bouillon, J. & Boero, F. (2000) Approaches to the ethology of hydroids and medusae (Cnidaria, Hydrozoa). In: Mills, C. E., Boero, F., Migotto, A. & Gili, J. M. (Eds.), Trends in Hydrozoan Biology - IV. Scientia Marina, 64 (Supplement 1), pp. 63 - 71. http: // dx. doi. org / 10.3989 / scimar. 2000.64 s 163", "Fraschetti, S., Giangrande, A., Terlizzi, A., Miglietta, M. P., Della Tommasa, L. & Boero, F. (2002) Spatio-temporal variation of hydroids and polychaetes associated with Cystoseira amentacea (Fucales: Phaeophyceae). Marine Biology, 140 (5), 949 - 957. http: // dx. doi. org / 10.1007 / s 00227 - 001 - 0770 - 9", "Faucci, A. & Boero, F. (2000) Structure of an epiphytic hydroid community on Cystoseira at two sites of different wave exposure. In: Mills, C. E., Boero, F., Migotto, A. & Gili, J. M. (Eds.), Trends in Hydrozoan Biology - IV. Scientia Marina, 64 (Supplement 1), pp. 255 - 264. http: // dx. doi. org / 10.3989 / scimar. 2000.64 s 1255", "Andreano, F. (2007) Identificazione degli idroidi (Cnidaria: Hydrozoa) nella fascia batimetrica dei 0 - 5 m. Degree Thesis, Marine Biology, University of Salento, 152 pp.", "Ostman, C. (1982) Nematocysts and taxonomy in Laomedea, Gonothyraea and Obelia (Hydrozoa, Campanulariidae). Zoologica Scripta, 11 (4), 227 - 241. http: // dx. doi. org / 10.1111 / j. 1463 - 6409.1982. tb 00536. x", "Schneider, K. C. (1898) Hydropolypen von Rovigno, nebst Uebersicht uber das System des Hydropolypen im Allgemein. Zoologische Jahrbucher, 10 (4), 472 - 555.", "Babic, K. (1910) Prilog Fauna Jadranskoga mora. Rad Jugoslavenske Akademije Znanosti i Umjetnosti. Zagreb, 183, 207 - 232.", "Babic, K. (1913 b) Bemerkungen zu den Zwei in der Adria vorkommenden thecaphoren Hydroiden. Zoologischer Anzeiger, 43, 284 - 288.", "Broch, H. (1912) Hydroidenuntersuchungen. Vergleichende Studien an Adriatischen hydroiden. Kongelige Norske Videnskabers Selskabs Skrifter, 1, 1 - 65.", "Vatova, A. (1928) Compendio della Flora et Fauna del Mare Adriatico presso Rovigno con la distribuzione geografica delle specie bentoniche. Memorie del Regio Comitato Talassografico Italiano, 143, 1 - 614.", "Leloup, E. (1934) Note sur les hydropolypes de la rade de Villefranche-sur-Mer (France). Bulletin du Musee Royal d'Histoire naturelle de Belgique, 10 (31), 1 - 18.", "Billard, A. (1936) Les fonds de peche pres d'Alexandrie. VI. Hydroidea. Notes and Memoires Ministere du Commerce et de l'Industrie, Egypte, 13, 1 - 11.", "Picard, J. (1951 a) Les hydraires des formations coralligenes des cotes francaises de la Mediterranee. Vie Milieu, 2 (2), 255 - 261.", "Picard, J. (1952) Les Hydrozoaires des herbiers de Zosteracees des cotes francaises de la Mediterranee. Vie Milieu, 2 (Supplement), 217 - 233.", "Picard, J. (1958 a) Origines et affinites de la faune d'hydropolypes (Gymnoblastes et Calyptoblastes) et d'hydromeduses (Anthomeduses et Leptomeduses) de la Mediterranee. Rapports et proces verbaux des Reunions de la Commission Internationale pour l'Exploration Scientifique de la Mer Mediterranee Monaco, 14, 187 - 199.", "Riedl, R. (1959) Die Hydroiden des Golfes von Neapel und ihr Anteil an der Fauna unterseeischen Hohlen. In: Ergebnisse der osterreichischen Tyrrhenia-Expedition 1952, Teil xvi. Pubblicazioni della Stazione Zoologica di Napoli, 30 (supplement), pp. 591 - 755.", "Riedl, R. (1966) Biologie der Meereshohlen. Blackwell Wissensch, 636 pp. http: // dx. doi. org / 10.1002 / iroh. 19680530208", "Rossi, L. (1961) Idroidi viventi sulle scogliere del promontorio di Portofino (Golfo di Genova). Annali del Museo Civico di Storia Naturale di Genova, 72, 68 - 85.", "Rossi, L. (1971) Guida a Cnidari e Ctenofori d'Italia. Quaderni della Civica Stazione Idrobiologica di Milano, 2, 1 - 101.", "Fey, A. (1970) Peuplements sessiles de l'archipel de Glenan. 1. - Inventaire: hydraires. Vie Milieu, B 20 (2), 387 - 414.", "Schmidt, H. E. (1973) Biogeographical problems of the Red Sea area exemplified by hydroids. In: Zeitschel, B. & Gerlach, S. A. (Eds.), The Biology of the Indian Ocean. Ecological studies, Analysis and Synthesis, 3, pp. 283 - 287. http: // dx. doi. org / 10.1007 / 978 - 3 - 642 - 65468 - 8 _ 22", "Chimenz Gusso, C. & Rivosecchi Taramelli, E. (1975) Idroidi del porto di Civitavecchia. Bollettino di Pesca, Piscicoltura e Idrobiologia, 30 (1), 111 - 125.", "Relini, G. & Romairone, V. (1976) Cicli di insediamento del fouling in condotte di un impianto di raffreddamento, in cui circola acqua di mare trattata con cloro. Archivio di Oceanografia e Limnologia, 18 (supplement 3), 231 - 256.", "Montanari, M. & Morri, C. (1977) Fouling di alcune piattiforme off-shore dei mari italiani: V. Gli Idroidi. Atti IX. Congresso della Societa Italiana di Biologia Marina, pp. 293 - 302.", "Repetto, L., Montanari, M. & Martini, F. (1977) Popolamenti di substrati artificiali posti su un fondo a coralligeno ed in una prateria di Posidonia. V: Idroidi. Atti del IX Congresso della Societa Italiana di Biologia Marina, Lacco Ameno d'Ischia, Napoli, 19 - 22 Maggio 1977, 415 - 425.", "Morri, C. (1979 b) Contributo alla conoscenza degli Idrozoi lagunari italiani: Idropolipi di alcuni laghi costieri mediotirrenici. Annali del Museo Civico di Storia Naturale Genova, 82, 163 - 171.", "Morri, C. (1980 b) Osservazioni sugli idroidi raccolti nelle condotte della centrale termoelettrica di Torvaldaglia (Civitavecchia). Natura, 71 (1 - 2), 3 - 14.", "Morri, C. (1981 a) Les Hydraires de quelques milieux lagunaires italien (Italie continentale et Sardaigne). Rapports et Proces Verbaux des Reunions, Commission Internationale pour l'Exploration Scientifique de la Mer Mediterranee, 27 (4), 193 - 194.", "Morri, C. (1981 b) Idrozoi lagunari. Guide per il riconoscimento delle specie animali delle acque lagunari e costiere italiane. Consiglio Nazionale delle Ricerche, Roma, AQ / 1 / 94, 6, 1 - 105. http: // dx. doi. org / 10.1002 / iroh. 19810660144", "Boero, F. (1981 a) Systematics and ecology of the hydroid population of two Posidonia oceanica meadows. Pubblicazioni della Stazione zoologica di Napoli, 2 (3), 181 - 197. http: // dx. doi. org / 10.1111 / j. 1439 - 0485.1981. tb 00093. x", "Boero, F. (1981 b) Bathimetric distribution of the epifauna of a Posidonia meadow of the Isle of Ischia (Naples): Hydroids. Rapports et Proces-Verbaux des Reunions Commision Internationale pour l'Exploration Scientifique de la Mer Mediterranee, Monaco, 27 (2), 197 - 198.", "Morri, C. & Martini, F. (1981) Gli idroidi della Laguna di Orbetello. In: Atti X. Congresso della Societa Italiana di Biologia Marina. Quaderni del Laboratorio di Tecnologia della Pesca, 3 (Supplement 1), pp. 305 - 313.", "Morri, C. & Bianchi, C. N. (1982) Contributo alla conoscenza degli idrozoi lagunari italiani: distribuzione di idropolipi lungo un gradiente ambientale nella laguna di Chioggia (Nord Adriatico). In: Atti XIV. Congresso della Societa Italiana di Biologia Marina. Bollettino dei Musei e degli Istituti Biologici dell'Universita di Genova, 50 (supplement), pp. 270 - 274.", "Isasi (Urdangarin), I. (1985) Fauna de Cnidarios bentonicos del abra de Bilbao. Memoria. Presentada para optar al grado de Licenciado en Ciencias Biologicas por Inigo Isasi Urdangarin. Universidad del pais Vasco. Euskal Herriko Unibersitatea. Facultad de Ciencias, Departemento de Biologia. Fauna of the benthic cnidarians of the Abra de Bilbao. Gratuation thesis, University of the Basque Country, 209 pp.", "Llobet, I., Gili, J. M. & Barange, M. (1986) Estudio de una poblacion de hidropolipos epibiontes de Halimeda tuna. Study of a population of epibiont hydropolyps on Halimeda tuna. Miscelanea Zoologica Barcelona, 10, 33 - 43.", "Roca, I. (1986) Estudio de los Cnidarios Bentonicos de las aguas costeras de Mallorca. Tesis, Universitat de les illes Balears, Facultat de Ciencies, Palma de Mallorca, 32 pp.", "Garcia-Rubies, A. (1987) Distribution of epiphytic hydroids on Posidonia sea grass. In: Bouillon, J., Boero, F., Cicogna, F. & Cornelius, P. F. S. (Eds.), Modern trends in the Systematics, Ecology and Evolution of Hydroids and Hydromedusae. Clarendon Press, Oxford, pp. 143 - 155. http: // dx. doi. org / 10.1017 / s 0025315400052255", "Ramil Blanco, F. J. (1988) Hidrozoos de Galicia. Memoria que, para optar al Grado de Doctor en Biologia, presenta D. Francisco Ramil Blanco. Facultad de Biologia, Universidad de Santiago. Santiago de Compostela, 525 pp.", "Morri, C., Bavestrello, G. & Bianchi, C. N. (1991) Faunal and ecological notes on some benthic cnidarian species from the Tuscan Archipelago and eastern Ligurian Sea (western Mediterranean). Bollettino dei Musei e degli Istituti Biologici dell'Universita di Genova, 54 - 55, 27 - 47.", "Bianchi, C. N., Ceppodomo, I., Niccolai, I., Aliani, S., De Ranieri, S., Abbiati, M., Dell'amico F. & Morri, C. (1993 b) Benthos dei Mari Toscani. II: Isola d'Elba-Montecristo (Crociera Enea 1986). In: Ferretti, O., Immordillo, F. & Damiani, V. (Eds.), Archipelago Toscano. Studio oceanografico, sedimentologico, geochimico e biologico. ENEA, Roma, Serie Studi Ambientali, pp. 291 - 315.", "Vervoort, W. (1993) Report on hydroids (Hydrozoa, Cnidaria) in the collection of the Zoological Museum, University of Tel- Aviv, Israel. Zoologische Mededelingen Leiden, 67 (40), 537 - 565.", "Migotto, A. E. (1996) Benthic shallow-water hydroids (Cnidaria, Hydrozoa) of the coast of Sao Sebastiao, Brazil, including a checklist of Brazilian hydroids. Zoologische Verhandelingen Leiden, 306, 1 - 125.", "Piraino, S., Brandini, E., Denitto, F., Esposito, L. & Avian, M. (1999) La diversita degli Cnidari nella riserva marina di Ustica. Biologia Marina Mediterranea, 6 (1), 272 - 274.", "Medel, M. D. & Vervoort, W. (2000) Atlantic Haleciidae and Campanulariidae (Hydrozoa, Cnidaria) collected during the CANCAP and Mauritania-II expeditions of the National Museum of Natural History, Leiden, The Netherlands. Zoologische Verhandelingen Leiden, 330, 1 - 68.", "Cinar, M. E., Katagan, T., Kocak, F., Ozturk, B., Ergen, Z., Kocatas, A., Onen, M., Kirkim, F., Bakir, K., Kurt, G., Dagli, E., Acik, S., Dogan, A. & Ozcan, T. (2008) Faunal assemblages of the mussel Mytilus galloprovincialis in and around Alsancak Harbour (Izmir Bay, eastern Mediterranean) with special emphasis on alien species. Journal of Marine Systems, 71 (1 - 2), 1 - 17. http: // dx. doi. org / 10.1016 / j. jmarsys. 2007.05.004", "Morri, C., Puce, S., Bianchi, C. N., Bitar, G., Zibrowius, H. & Bavestrello, G. (2009) Hydroids (Cnidaria: Hydrozoa) from the Levant Sea (mainly Lebanon), with emphasis on alien species. Journal of the Marine Bioogical Association of the United Kingdom, 89 (1), 49 - 62. http: // dx. doi. org / 10.1017 / s 0025315408002749", "Bianchi, C. N., Dando, P. R. & Morri, C. (2011) Increased diversity of sessile epibenthos at subtidal hydrothermal vents: seven hypotheses based on observations at Milos Island, Aegean Sea. Advances in Oceanography and Limnology, 2 (1), 1 - 31. http: // dx. doi. org / 10.1080 / 19475721.2011.565804"]}