Search

Eirene viridula (P��ron & Lesueur, 1809) Distribution in South America: medusa���Atlantic Ocean, Colombia to Brazil, from 10��N to 0�� (Equator) (Alvari��o 1968; Migotto et al. 2002)., Published as part of M. P. Oliveira 1,16, S P. Miranda 2, *,, Es W. Mianzan 10,, Ro E. Migotto 11,, Ne B. Nascimento 2,11, Eli Nogueira J��nior 12,, Er Qui��ones 13,, Izio Scarabino 14,, T��n Schiariti 10,, Io N. Stampar 15,, Tronolone 2, , Qu��ria B. & Onio C. Marques 2,11, 2016, Census of Cnidaria (Medusozoa) and Ctenophora from South American marine waters, pp. 1-256 in Zootaxa 4194 (1) on page 148, DOI: 10.11646/zootaxa.4194.1.1

Eirene viridula (Péron & Lesueur, 1809) Distribution in South America: medusa—Atlantic Ocean, Colombia to Brazil, from 10°N to 0° (Equator) (Alvariño 1968; Migotto et al. 2002).

Eirene viridula (P��ron and Lesueur, 1810) Fig. 58 A, B See Kramp (1961) for a complete synonymy. Material examined. HCUS-S 0 65 (Hydrozoa Collection, University of Salento���fauna of the Salento Peninsula)���polyp stage. Description (after Metschnikoff 1886 a; Russell 1953; Cornelius 1995): Hydroid. Hydrorhiza as branching or anastomosing stolons; colonies erect; hydrocauli short, with perisarc smooth to sinuous throughout; hydranths of Campanopsis type, with cylindrical body tapering slightly basally, ca 5 on each hydrocaulus; hypostome conical-rounded; with about 10���24 amphicoronate oral filiform tentacles, intertentacular membranous basal web reported; hydrothecae reduced or lacking, depending on age; gonothecae oblong, round-truncated above and below, with thin walls, long, possibly dropping during medusa development, probably containing a single medusa bud each. Habitat type. Depth range: 0.5��� 3 m (Faucci & Boero 2000). Substrate. Cystoseira (brown alga). Seasonality. February���December (Faucci & Boero 2000; Galea 2007) in the Mediterranean Sea. Reproductive period. April���May, June���October (Gili 1986) in the western Mediterranean. Medusa. Adult. Umbrella hemispherical, up to 30 mm wide or even larger, mesoglea of middle portion fairly thick, thinner at sides; manubrium fairly short, small, mounted on an elongated and slender gastric peduncle reaching beyond exumbrellar margin; mouth with 4 very long pointed lips with crenulated margins; 4 radial canals and circular canal narrow; gonads linear, straight, slightly sinuous, limited to disk of subumbrella, extending from somewhat beyond base of peduncle almost to exumbrellar margin; velum narrow; about 70 or more conical marginal bulbs; each with one tentacle of different size, small and large alternating; with distinct excretory papillae; 50 or more statocysts. Colours: colourless except for greenish tinge on stomach. Developmental stages. The first stage of E. viridula, after liberation from the hydroid, has not been observed. The youngest observed specimens have bell-shaped umbrella, 1.5 mm high and wide; manubrium short, without gastric peduncle; mouth with 4 distinct short lips; 4 narrow radial canals and ring canal; gonads not visible; 4 perradial marginal tentacles with rounded bases; 8 statocysts, one on either side of each marginal tentacle, each with one concretion. E. viridula medusa is already differentiated at a size of 2.0���2.5 mm by having a small peduncle. The gonads usually appear as elongated thickenings on the radial canals when the medusa is 3.5���4.0 mm in diameter (for more details about the medusa development see Russell 1953). Colours: brown pigment in the endoderm of the bases of the marginal tentacles, and also at the base of the stomach and extending interradially as far as the mouth. Cnidome. Atrichous and basitrichous isorhizas (hydroid); atrichous isorhizas and microbasic mastigophores (medusa). Distribution. Atlantic, Indo-Pacific, Mediterranean (Russell 1953; Cornelius 1995; Medel & L��pez-Gonz��lez 1996; Bouillon et al. 2004; Gravili et al. 2008 a). Records in Salento. Rare at La Strea, Porto Cesareo (Faucci & Boero 2000). Remarks. Perigonimus nudus Stechow, 1919 was recognized as a new synonym of Eirene viridula (P��ron and Lesueur, 1810) by Schuchert (2007). In its earliest stages, the medusa of E. viridula bears a very close resemblance to that of Clytia hemisphaerica, but its gonads are more elongated and more proximally placed than in Clytia (Russell 1953). Gonothecae and medusae not seen in the present study. References. Mayer (1910), Russell (1953), Tr��gouboff & Rose (1957), Picard (1958 a), Anichini (1959), Rossi (1971), Goy (1973), Schmidt (1973), Benović (1977), Schmidt & Benović (1979), Dowidar (1984), Lakkis & Zeidane (1985), Castello i Tortella (1986), Gili (1986), Benović & Bender (1987), Goy et al. (1988, 1990, 1991), Benović & Lučić (1996), Medel & L��pez-Gonz��lez (1996), Benović et al. (2000), Faucci & Boero (2000), Bouillon et al. (2004), Galea (2007), Gravili et al. (2008 a)., 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 84-86, DOI: 10.11646/zootaxa.3908.1.1, http://zenodo.org/record/242729, {"references":["Kramp, P. L. (1961) Synopsis of the medusae of the world. Journal of the Marine Biological Association of the United Kingdom, 40, 1 - 469. http: // dx. doi. org / 10.1017 / s 0025315400007347","Metschnikoff, E. (1886 a) Medusologische Mittheilungen. Arbeiten aus dem zoologischen Institut der Universitat Wien, 6, 237 - 266.","Russell, F. S. (1953) The medusae of the British Isles, Anthomedusae, Leptomedusae, Limnomedusae, Trachymedusae and Narcomedusae. London, Cambridge University Press, 530 pp. http: // dx. doi. org / 10.1126 / science. 119.3095.562","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.","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","Galea, H. R. (2007) Hydrozoa, La Ciotat and nearby areas, Mediterranean coast of France. Check List, 3 (3), 193 - 199.","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.","Gravili, C., Boero, F. & Licandro, P. (2008 a) Hydrozoa. Biologia Marina Mediterranea, 15 (Supplement), 71 - 91.","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.","Mayer, A. G. (1910) Medusae of the world. Hydromedusae. Vol. I & II. Washington, Carnegie Institution, 735 pp.","Tregouboff, G. & Rose, M. (1957) Manuel de Planctonologie Mediterraneenne. Tome I & II. C. N. R. S., Paris, 587 pp. & 31 pls. [pls. 62 - 93].","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.","Anichini, C. (1959) Risultati dei primi dodici mesi delle ricerche planctonologiche eseguite dall'Instituto di Zoologia di Cagliari nell'Anno Geofisico Internazionale. Bollettino di Zoologia, 26 (2), 669 - 682. http: // dx. doi. org / 10.1080 / 11250005909439316","Rossi, L. (1971) Guida a Cnidari e Ctenofori d'Italia. Quaderni della Civica Stazione Idrobiologica di Milano, 2, 1 - 101.","Goy, J. (1973) Les Hydromeduses de la mer Ligure. Bulletin du Museum National d'Histoire naturelle, Paris, Serie 3 (Zoologie), 83 (62), 965 - 1008.","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","Benovic, A. (1977) Bathymetric distribution of hydromedusae (Cnidaria) at one station in the Southern Adriatic. Rapports et Proces-Verbaux des Reunions Commision Internationale pour l'Exploration Scientifique de la Mer Mediterranee, Monaco, 24 (10), 101 - 102.","Schmidt, H. E. & Benovic, A. (1979) Cruises of R / V \" Vila Velebita \" in the Kvarner region of the Adriatic Sea, XII. Hydromedusae (Cnidaria). Thalassia Jugoslavica, 15 (3 - 4), 193 - 202.","Dowidar, N. M. (1984) Medusae of the Egyptian Mediterranean waters. In: Rapport de Journees d'etude sur la proliferation anormales de meduses en Mediterranee. United Nations Environment Programme, pp. 9 - 16.","Lakkis, S. & Zeidane, R. (1985) Les hydromeduses des eaux neritiques libanaises: composition et distribution. Rapports et Proces-Verbaux des Reunions Commision Internationale pour l'Exploration Scientifique de la Mer Mediterranee, Monaco, 29 (9), 179 - 180.","Castello, I & Tortella, G. (1986) Cnidarios planctonicos de superficie: Faunistica y factores de distribucion en la costa Catalana. Memoria realizada por D. Gabriel Castello i Tortella para optar al grade de Licenciado por la facultad de Biologia de la Universidad de Barcelona, 201 pp.","Goy, J., Lakkis, S. & Zeidane, R. (1988) Les Meduses de la Mediterranee orientale. Rapports et Proces-Verbaux des Reunions Commision Internationale pour l'Exploration Scientifique de la Mer Mediterranee, Monaco, 31 (2), 299.","Goy, J., Lakkis, S. & Zeidane, R. (1990) Les Meduses de la Mediterranee orientale. In: Godeaux, J. (Ed.), A propos des migrations lessepsiennes. Bulletin de l'Institut Oceanographique de Monaco, No. Spec. 7, pp. 79 - 88.","Goy, J., Lakkis, S. & Zeidane, R. (1991) Les meduses (Cnidaria) des eaux Libanaises. The medusae Cnidaria of Lebanese waters. Annales de l'Institut Oceanographique de Monaco, 67 (2), 99 - 128.","Benovic, A. & Lucic, D. (1996) Comparison of hydromedusae findings in the northern and southern Adriatic Sea. In: Piraino, S., Boero, F., Bouillon, J., Cornelius, P. F. S. & Gili, J. M. (Eds.), Advances in Hydrozoan Biology. Scientia Marina, 60 (1), pp. 129 - 135.","Benovic, A., Lucic, D., Onofri, V., Peharda, M., Caric, M., Jasprica, N. & Bobanovic-Colic, S. (2000) Ecological characteristics of the Mljet Island seawater lakes (South Adriatic Sea) with special reference to their resident populations of medusae. In: Mills, C. E., Boero, F., Migotto, A. & Gili, J. M. (Eds.), Trends in Hydrozoan Biology - IV. Scientia Marina, 64 (Supplement 1), 197 - 206. http: // dx. doi. org / 10.3989 / scimar. 2000.64 s 1197"]}

Colonial hydroids expand by means of vascular tubings, termed stolons, which elongate, generate new polyps, and branch at regular intervals. The pattern of the resulting network is controlled by specialized distal organs, the stolon tips. Two factors are described which activate or inhibit, respectively, stolon tip formation. Both factors emanate from existing tips. The activating factor is released into the medium and stimulates, in adjacent stolons, lateral tip formation and, hence, branching. A transplanted tip not only induces tip formation over distances of up to 140 μm but also attracts the induced tip by guiding the direction of its movement. Upon contact both tips fuse, provided the encounter occurs between isogeneic or histocompatible stolons, and an anastomosis is formed. The inhibitory principle appears to be transmitted within the stolon and is used to control branching distances. However, measurable traces of inhibitory activity leak into the medium. The factor is of low molecular weight. The activating and the inhibiting factors are both found in two distantly related colonial species—Hydractinia echinata (Athecata) and Eirene viridula (Thecata).