Reu. Mus.A rgentina Cienc. Nat., n.s. 3(1): 73-76, 2001 Buertus Area, ISSN 1514-5158 Presence of Beania mirabilis Johnston in the Gulf of San Matias (hgentina),w ith a key to the Argentine species of Beania I (Bryozoa, Cheilostomatida) Juan LOPEZ GAPPA Museohrgentino de Cicncias Naturales dernardino ltivadavia~>,AAv. ,G allardo 470, C1405DJR Buenoshires, Argentina. E-mail: 1gappahail.rctina.ar Abstracl: Beanirt mirabilis Johnston is recorded far the firstt ime inArgentina.I t was found on bivalve shells and polychnete tubes in tbe intertidal and subtidal zones ofthe Gulf of Sanhlatias (40" 46'8, 64" 65'W,provinceo fRio Ne~o,Argentina).'Chisre cord increases in more than 16" oflatitude its southern distribution lunit in the southwest Atlantic Occan. An illustrated key for the identiiicalion of the eight species of Beania known for the Argentine Sea is included. Key words: Bryozoa, Cheilostomatida, Beaniii, key to species,A rgentina The genus Beania Johnston, 1840, comprises species of this genus. It was originally described more than 50 species distributed throughout the from matcrit~lc ollected by Charles Darwin in world's oceans, including Antarctica. Reuniu is Patagonia and Cape Horn, although without characterized by its reticulate or ramifiing giving precise localities within this region. B. colonies, with zooids loosely attached to the australis was found again just once, off the state substratum by rhizoids issuing from their basal of Szo Paulo, Brazil. This unlikely distribution surfaces, and connected by tubular extensions. was confirmed, however, by the comparison of Several species of Beania have been already the Brazilian material with the type specimens recorded for the coast and the continental shelf of the species (Marcus, 1937). of' Argentina (see Hastings, 1943; Amor & While processing intertidal and subtidal Pallares, 1965; L6pez Gappa & Lichtschein, samples of benthic invertebrates from the Gulf 1990). The geographic distribution of H. costutu of San Maticis, several colonies of a species of (Busk, 18761, B. fragilis (Ridley, 18811, B. Beania still unrecorded for Argentina were znerrnis (Busk, 1852), B. magellanica (Busk, discovered. It was identified as Beania mirabzlis 18521,B.m axilla (Jullien, 1888) andB. unicornis Johnston, 1840, a widely distributed species, (I-Iastings, 1943) between 35" and 56" S, and whose southern distribution limit known to date between 50" W and the coast of Argentina has in the southwest Atlantic Ocean was Brazil. The been summarized by L6pez Gappa (2000), and aim of this study is to document its presence in maps showing known records of five species in coastal waters of Argentina. In addition, an the Patagonian shelf have been published by illustrated key for the Argentine species of L6pez Gappa & Lichtschein (1990). Beania is presented, in order to facilitate their These species are usually found in cold- identification by other marine researchers not temperate waters under the influence of the Familiar with the taxonomy of this group of Malvinas Current. They have been recorded for benthic invertebrates. the Maeellan Strait. Cane Horn. the Burdwood Bank, &ound.the Malv;nas (Falkland) Islands, Reania mirabilis Johnston, 1840 and along the coast and continental shelf off the (Figs. 1, 2) provinces of Tierra del Fuego, Santa Cruz and Chubut' Only maxizla extends further north Beanie rnirehilis Johnston, 1840:272,figs.1 ,2. in Argentina, towards deeper shelf areas ,nirabilis: M ~1937:~ 60, ~~11fi,g~ . 29 , province of Buenos Aires (Roux et al., 1988). (Synonymy). A little known species, B. australis Busk, BeaIaiaI nirabilis: Ryland & Flayward, 1977: 150,fig. 1852, can be added to the list of Argentine 73. Revista del Museo Argentino de Ciencias Nata~ales,n . s. 3 ilj, 2001 S, 64" 63 W) Low intertidal and subtldal (0-5 m),VanVeen grab 26103199, collected by J 1,opez Gappa MACK 34615 On Brachzdontes rodr~guezls hells and polychaete tubes Geographic Distribution B. mirabilis is widely distributed in temperate and tropical waters of the Atlantic, Indian and Pacific Oceans, although its geographic range seems to be based on more than one species (see below). 111 the south Atlantic, it has been previously recorded only for Santa Helena Island (Marcus, 1938) and S&o Panlo, Brazil (24" S) (Marcus, 1937). Its southern distribution limit in this ocean is therefore ex- tended in more than 1.6" of latitude. From the intertidal zone up to B depth of 130 m (Marcus, 1937). Obseruations Figs. 1-2. Beania mirabilis ,Johnston, 1840. Pun- lnconspicuous colonies or this species were ta Delgado, Gulf of San Matias, MACN 34615. found in the intertidal zone, on shells of the Scale: 0.6 mzn. 1, Frontal view of zooid. 2, Late- mytilid Brachidontes rodriguezi densely ral view of zooid. encrusted by spirorbid polychaehes. Less frequent substrata were stones and the mussel Mytilus edulis platensis. Other members of this Diagnosis association were the rodophyte Polysiphonia sp., Colony uniserial, ramified. Zooids suberect, the bryozoan C~yptosulapallasiara~nad sponges. 0.55-0.60 mm long, spaced 1.1-1.7 zooid lengths In subtidal samples, B. mimbilis was found on from each other, anchored to the substratum by B, rodriguezi shell fragments cemented to rhizoids and connected by stolons. Three stolons polychaete tuhes, together with the bryozoan per zooid, issuing latero- and mebio-proximally Celleporella hyalina. from the base of the zooid. Two pairs of short In a recent study, Tilbrook el a?. (2001) and erect spines around the operculum. Usually reported that several specimens apparently 6 (sometimes 7 or 8) pairs of sho1.t and delicate belonging to B. rnirabilis from Australia, spines on each lateral margin, arched over the Vanuatu and the Mediterranean,might actually frontal membrane. Avicularia and ovicells be regarded as iicw species, Differ,ences in zooid absent. length and spacing, and number of marginal spines between the I'atagonian material and Material British specimens ofB. mirabilis are very slight, Punta Delgado, Gulf of San Matias, province and do not seem to justify the introduction of a of Rio Negro, Argentilia (approximately 40-46' new species. KEY TO THE ARGENTINE SPECIES OF BEANIA 1 1. Usually onc or two avicularia per zooid, facing frontally - Avicularia absent, or less frequent and pointing toward 2. Marginal spines arched over the frontal membrane. Usually one avicularia per zooid .......... 3 - Marginal spines absent. Two avicularia per zooid ...............................R.. magellanica (Fig. 3) 3. Three pairs of erect spines around the operculum. Operculum bearing one pair of irregularly star-shaped processes B, maxilla (Fig. 4) g one pair of horn-shaped B costata (Fig. 5) - Zooids erect or suberect . 5. Marginal spines delicat , . .. . .. , .. . . . . . I Ldpez Gappa Presence of Beania mzrabzl~si n Argentzna Figs. 3-10. Schematic view of zooids in the 8 species of Beania recorded for Argentina. 3, Beania magellanica. 4, B. maxilla. 5, B, coslata. 6,B. inermis. 7, B. unicornis. 8, B. fragilis. 9, B. mirabilis. 10, B. australis. Figs. 3-7, frontal view, Figs. 8-10, lateral view. Not to scale. Modified from Ldpez Gappa & Lichtschein (1990) (Figs. 3-5 and 8), Amor & Pallares (1965) (Fig. 61, Hastings (1943) (Fig. 71, Ryland & Hayward (1977) (Fig. 9), and Marcus (1937) (Fig. 10). 76 Reuzsta rlel Museo Argentzno de Czenczas Nalurales, 12 s 3 (I), 2001 - Numerous and well developed marginal spines. Zooids well separated among each other .............. ................................ ...................................................................................... B. unicornis (Fig. 7) 6. Spines numerous, long, and conspicuous, located even at the dorsal surface of the zooid, pointing . . in all d~rections.. ..................... ... ...............................................................B. . fragilis (Fig. 8) - Spines only along the edge of the frontal membrane, or around the opercuium ..................... 7 7. Spines short and delicate, not covering the frontal membrane .................. B. mimbilis (Fig. 9) - Two series of well developed spines covering the frontal membrane ....... B australis (Fig. 1.0) ACKNOWLEDGEIVIENTS 1883). Zoo1 6 1-94 Cauthiei-Villdrs et Cie Paris Lopez Gappa, J 2000 Species rlchnoss of mar.in*e- 1 am indebted to ~~~~~d~ ~ ~ and~ ~Bryo~koain tdhe con tinental shelf and slope off Alejandro for their advice on the use of gentina (south-west Atlantic). Diurrsity and Distributions, 6: 15-27. soft~refo r the design and edition of digital Lhi,ez Craplla, J. & ". Lichtschein. 1990. briozoos images. The National Council for Scientific ,,~,,,i,,,~i~s pore ~ ~ / ~ ~ j ~ i , ~ h ~ i ~ ~ ~ ~ ~ l ~ ~ l ~ ~ ~ . Research and Technology (CONICETI of Argen- lbrma continental nreentina. Scm. Hidraer. Na- tina is gratefully acknowledged fir financial val, Buenos Aires, :i2 pp. v support to the author during the course of this Marcus, E. 1937.B ryozo:iriosrniirinhos brasileiros. I.Bol. study. Fat. Phil. Sei. Letr. Uniu. SrioPaulol, Zool. 1: 1-224. - 1938. Papers from Dr. Th. Mortensen's I'acifie BIBLIOGRAPHY Expedition 1914 - 16. LXIX. Bryozoen von St. Helena. Vidensh. Medd. Ilaiisk. Naturh. Foren. 101: 183-252. Ridley, S.O. 1881. Polyzoa, iiccount of the zoalogieal collection durine the sumev of 1I.M.S.A lert in the " Strait of Magellan and on the coast of Patagonia. 291-317. Roc. Zoo1 Soc., pp. 44-61 Dusk, G. 1852. Cataluzue ofthe ,narine Polyzoa in the Roux. A.. Bastida.. R... Lichtschein.V. &A. Barreto. 1988. collectio,i of the British Museu,,~. Part I. , , Investigacianes sobre las comunidades bentdnicas Cheilostornato (part), pp. 1-54. Trustees of the de platafanna a traves de una transecta kcnte a British Museum (Natural History), 1,ondon. -- 1876. Ilcscription of some new species of Polgzaa Mar del Plata. Sohenisci~r6 : 19-52. - Ryland, J.S. & P.~.'~aywar1d9.7 7. British Anascan froin Kerruelen's is1and.Ann Mae. Hat, 1Iist.. ser. bryozoans. Syi~opseso f the British fauna f,i.s.),1 0. 4,17: 11~118. Acadcmic Press, London, 188 pp. Hastings, A.B. 1943. Polyzoa (Bryozoa). I. Tilbrook, K.J., Hayward, P.J. & D.P. Gordon. 2001. Scrupocellariidiie, Epistomiidae, Farciminariidae, Chcilostomataus Bryoaoa from Vanuatu. Zool. J Bieellariellidae, Aeteidae, Scrupariidac. Diseouery Linn Soc. 131: 35-109. Rep. 32: 301-510. Johnston, G. 1840. Descrintionofa new n- enusofBritish zoophyte.A,in. Mag. Hal. Flist., ser. 1, 6: 272-274. Recihido: 31-VIlI-2000 Jullien, J. 1888. Bryozoaires.Miss. Sci. Cup Horn 12882- Aceptado: 15-XII-2000