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Exidmonea zagorseki sp. nov. (Figs 3B–C, 5A–F) Material examined. Type material. MNRJ-183 (holotype), MNRJ-238 (paratype), Região dos Lagos, Rio de Janeiro State, 23°47.629’S, 041°42.514’W, 20 July 2004, collector D.C. Savi, depth 341 m. Diagnosis. Colony arborescent, dichotomously branched, autozooidal apertures isolated or grouped into pairs or threes, alternating on each side of branch midline; peristome elongate, slightly curved; branch dorsal side flattened with small pseudopores and arcuate growth bands; gonozooid on frontal side, forked at branch bifurcation; ooeciostome short, unicuspate, with circular ooeciopore. Description. Colony arborescent, dichotomously branched, in some parts with branches twisted around their longitudinal axes, strongly calcified, originating from well-developed and wide base (Fig. 5A, B). Sterile branch diameter (average 441 µm) usually slightly smaller than distance between autozooidal series (average 588 µm). Flattened dorsal side of branches with arcuate growth bands, lacking kenozooidal overgrowth. White in colour. Autozooids tubular with long (at least 200 µm) well-developed peristomes, these slightly curved outwards and upwards (Fig. 5C–D); frontal wall transversely wrinkled; apertures disposed alternately in connate series comprising 2–3 apertures, sometimes solitary, opening on frontal side of colony (Fig. 5B–E), zooidal boundaries marked by fissures; aperture circular (Fig. 5C). Basal, frontal and dorsal walls perforated by small pseudopores, rounded or slightly longitudinally elongate (10–(11)–12.5 µm long x 5–(6.75)–10 µm wide) (Fig. 5E–F). Gonozooid located on branch frontal side, extending between autozooidal apertures; originating proximal to bifurcation and extending into both daughter branches as far as 2nd or 3rd autozooidal series. Gonozooid large (2370 µm long x 437 µm wide), diffuse; frontal wall densely pseudopores (Fig. 3B); ooeciostome short, ending in a circular, unicuspate ooeciopore (Fig. 3C). Etymology. In honour of Dr Kamil Zagorsek, bryozoan specialist at the Narodni Museum, Prague. Remarks. The genus Exidmonea contains a large number of species, the majority of which are Cretaceous or Cenozoic fossils. There are, however, many recent species known from, for example, the Mediterranean, the Philippines and the Antarctic. Of the Exidmonea species described previously from Brazil, E. foresti (Buge, 1979) has one to three autozooids per series and a gonozooid located close to the branch bifurcation, as in E. zagorseki sp. nov. The width of the branch (140–200 µm), however, and the distance between fascicles (200–320 µm) are appreciably larger than in E. zagorseki sp. nov. Exidmonea atlantica (Forbes in Johnston, 1847) differs from E. zagorseki in having three to five autozooids per series, wider branches (280–350 µm), and gonozooids not associated with branch bifurcations. The presence of secondary calcification at the colony base, obscuring the older autozooids and the general form of the colony, recalls E. hula (Borg, 1944), which normally has, however, up to four autozooids in each series and shorter peristomes. The Antarctic species E. arcuata Ostrovsky & Taylor, 1996 is similar to E. zagorseki but differs in having a weakly calcified colony, branches that bend strongly backwards (dorsally), and two to five autozooidal apertures per series (normally three to four). According to Ostrovsky and Taylor (1996), the colony begins from a Stomatopora -like base, followed by a supporting disc from which two or three new branches originate. This is not observed in E. zagorseki where the base produces a single erect stem. Another Antarctic species, E. curvata (Borg, 1944), resembles E. zagorseki in having a well-developed colony base and branches that are slightly curved backwards. Exidmonea curvata differs, however, in having three to five autozooids per series, a long, ooeciostome with bilabiate ooeciopore that is almost slit-like, and gonozooids that do not fork at branch bifurcations. Ecology. Colonies were found on calcareous rocks in deeper waters (341 m). Geographic distribution. Região dos Lagos (23°47.629’S, 41°42.514’W), Rio de Janeiro State.

Disporella pila Marcus, 1955 (Fig. 9A–F) Disporella pila Marcus, 1955: 277; Buge 1979: 243. Material examined. MNRJ-191, MNRJ-365: Arraial do Cabo Farol beach, Cabo Frio Island, 1 March 2002, collector L. V. Ramalho, depth 5 m. Description. Colony almost circular, encrusting, small, up to 5 mm diameter, white; basal lamina free, sometimes elevated from substratum, growing edge thick (Fig. 9A). Autozooids tubular, apertures circular (50–(63)–80 µm), grouped in uniserial rows (Fig. 9A, B); orientated at low angle to colony surface, their tubular walls clustered into radial ridges, some central autozooids growing freely and irregularly; apertures bicuspate, opening laterofrontally, mostly close to growing edge (Fig. 9A–C). Calcification entirely cryptocystal (Fig. 9C). Alveoli polygonal (62–(78)–100 µm diameter), interspersed among autozooids, their apertures larger than autozooidal apertures in central region, usually forming uniserial rows between autozooids in outer parts of colonies (Fig. 9C–D), containing mural spinules with star-shaped crowns (Fig. 8E). Basal lamina with flattened, distally imbricated crystallites (Fig. 9A–B, F). Gonozooid not observed. Remarks. The taxonomy of lichenoporids is more problematical than that of most other groups of cyclostomes because very little is known about variations in skeletal morphology in relation to the age and reproductive state of colonies. Species of Disporella from the Atlantic and Mediterranean were revised by Alvarez (1992, 1994, 1995) but D. pila was not considered in these publications. Disporella pila differs from other species in the acute angle of the autozooidal tubes to the colony surface, with the result that the apertures open laterofrontally, almost parallel to the substratum. The Rio de Janeiro material differs from D. pila as described by Marcus (1955) and Buge (1979) from the Espírito Santo coast, which have fewer rows of autozooids and a more frequently elevated basal lamina. These differences are minor, however, and the Rio de Janeiro material is identified as D. pila. Ecology. Colonies found encrusting the alga Sargassum at 5 m depth; Marcus (1955) also collected D. pila on non-calcareous algae. Geographic distribution. Espírito Santo (Vitória) and 21°10’ – 21°38’S, 40°42’ – 40°45’W (Marcus 1955; Buge 1979); Arraial do Cabo (Cabo Frio Island), Rio de Janeiro State (present study)., Published as part of Ramalho, L. V., Muricy, G. & Taylor, P. D., 2009, Cyclostomata (Bryozoa, Stenolaemata) from Rio de Janeiro State, Brazil, pp. 32-52 in Zootaxa 2057 on page 47, {"references":["Marcus, E. (1955) Notas sobre Briozoos Marinhos Brasileiros. Arquivo do Museu Nacional, 42, 273 - 324.","Buge, E. (1979) Bryozoaires Cyclostomes. Annales de l'Institut Oceanographique. Resultats Scientifiques des Campagnes de la Calypso, n. s., 11, 55: 207 - 252.","Alvarez, J. A. (1992) Sobre algunas especies de la familia Lichenoporidae Smitt, 1866 (Bryozoa, Cyclostomida) en la region Atlantico-Mediterrananea. Parte I: genero Disporella Gray, 1848. Cahiers de Biologie Marine, 33, 201 - 243.","Alvarez, J. A. (1994) La famille des Lichenoporidae (Bryozoa, Cyclostomida) dans les provinces Atlantico- Mediterraneenne et Boreale. Part III: etude des collections du Museum National d'Histoire Naturelle de Paris. Cahiers de Biologie Marine, 35, 491 - 509.","Alvarez, J. A. (1995) New data on the family Lichenoporidae Smitt (Bryozoa: Cyclostomida) from the Mediterranean region. Journal of Natural History, 29, 1067 - 1079."]}

Exidmonea zagorseki sp. nov. (Figs 3B–C, 5A–F) Material examined. Type material. MNRJ-183 (holotype), MNRJ-238 (paratype), Região dos Lagos, Rio de Janeiro State, 23°47.629’S, 041°42.514’W, 20 July 2004, collector D.C. Savi, depth 341 m. Diagnosis. Colony arborescent, dichotomously branched, autozooidal apertures isolated or grouped into pairs or threes, alternating on each side of branch midline; peristome elongate, slightly curved; branch dorsal side flattened with small pseudopores and arcuate growth bands; gonozooid on frontal side, forked at branch bifurcation; ooeciostome short, unicuspate, with circular ooeciopore. Description. Colony arborescent, dichotomously branched, in some parts with branches twisted around their longitudinal axes, strongly calcified, originating from well-developed and wide base (Fig. 5A, B). Sterile branch diameter (average 441 µm) usually slightly smaller than distance between autozooidal series (average 588 µm). Flattened dorsal side of branches with arcuate growth bands, lacking kenozooidal overgrowth. White in colour. Autozooids tubular with long (at least 200 µm) well-developed peristomes, these slightly curved outwards and upwards (Fig. 5C–D); frontal wall transversely wrinkled; apertures disposed alternately in connate series comprising 2–3 apertures, sometimes solitary, opening on frontal side of colony (Fig. 5B–E), zooidal boundaries marked by fissures; aperture circular (Fig. 5C). Basal, frontal and dorsal walls perforated by small pseudopores, rounded or slightly longitudinally elongate (10–(11)–12.5 µm long x 5–(6.75)–10 µm wide) (Fig. 5E–F). Gonozooid located on branch frontal side, extending between autozooidal apertures; originating proximal to bifurcation and extending into both daughter branches as far as 2nd or 3rd autozooidal series. Gonozooid large (2370 µm long x 437 µm wide), diffuse; frontal wall densely pseudopores (Fig. 3B); ooeciostome short, ending in a circular, unicuspate ooeciopore (Fig. 3C). Etymology. In honour of Dr Kamil Zagorsek, bryozoan specialist at the Narodni Museum, Prague. Remarks. The genus Exidmonea contains a large number of species, the majority of which are Cretaceous or Cenozoic fossils. There are, however, many recent species known from, for example, the Mediterranean, the Philippines and the Antarctic. Of the Exidmonea species described previously from Brazil, E. foresti (Buge, 1979) has one to three autozooids per series and a gonozooid located close to the branch bifurcation, as in E. zagorseki sp. nov. The width of the branch (140–200 µm), however, and the distance between fascicles (200–320 µm) are appreciably larger than in E. zagorseki sp. nov. Exidmonea atlantica (Forbes in Johnston, 1847) differs from E. zagorseki in having three to five autozooids per series, wider branches (280–350 µm), and gonozooids not associated with branch bifurcations. The presence of secondary calcification at the colony base, obscuring the older autozooids and the general form of the colony, recalls E. hula (Borg, 1944), which normally has, however, up to four autozooids in each series and shorter peristomes. The Antarctic species E. arcuata Ostrovsky & Taylor, 1996 is similar to E. zagorseki but differs in having a weakly calcified colony, branches that bend strongly backwards (dorsally), and two to five autozooidal apertures per series (normally three to four). According to Ostrovsky and Taylor (1996), the colony begins from a Stomatopora -like base, followed by a supporting disc from which two or three new branches originate. This is not observed in E. zagorseki where the base produces a single erect stem. Another Antarctic species, E. curvata (Borg, 1944), resembles E. zagorseki in having a well-developed colony base and branches that are slightly curved backwards. Exidmonea curvata differs, however, in having three to five autozooids per series, a long, ooeciostome with bilabiate ooeciopore that is almost slit-like, and gonozooids that do not fork at branch bifurcations. Ecology. Colonies were found on calcareous rocks in deeper waters (341 m). Geographic distribution. Região dos Lagos (23°47.629’S, 41°42.514’W), Rio de Janeiro State., Published as part of Ramalho, L. V., Muricy, G. & Taylor, P. D., 2009, Cyclostomata (Bryozoa, Stenolaemata) from Rio de Janeiro State, Brazil, pp. 32-52 in Zootaxa 2057 on pages 39-41, {"references":["Buge, E. (1979) Bryozoaires Cyclostomes. Annales de l'Institut Oceanographique. Resultats Scientifiques des Campagnes de la Calypso, n. s., 11, 55: 207 - 252.","Johnston, G. (1847) A History of the British Zoophytes. 2 nd edn, John van Voorst, London, xvii + 488 pp., 74 pls (vol. 2).","Borg, F. (1944) The stenolaematous Bryozoa. Further Zoological Results of The Swedish Antarctic Expedition 1901 - 1903, 3, 5: 1 - 276, 16 pls.","Ostrovsky, A. N. & Taylor, P. D. (1996) Systematics of some Antarctic Idmidronea and Exidmonea (Bryozoa: Cyclostomata). Journal of Natural History, 30, 1549 - 1575."]}

Mecynoecia cf. delicatula (Busk, 1875) (Fig. 7A–F) Pustulopora delicatula Busk, 1875: 20. Entalophora delicatula: Marcus 1937: 24. Mecynoecia delicatula: Buge 1979: 221. Material examined. MNRJ-364, Baía da Guanabara, Rio de Janeiro city, 10 April 2002, collector J.E.A. Gonçalves, depth 2 m. Description. Colony erect, almost 11 mm long in single available example, dichotomously branched (Fig. 7A), white, basal portion broken, branch diameter 380–(460)–517 µm. Autozooids opening around entire branch, 8–10 in one circumference, frontal wall transversely wrinkled, pseudopores small (about 7 µm in diameter). Peristomes (356–(418)–630 µm long x 100–(110)–120 µm wide) gently curved frontodistally, mostly broken off (Fig. 7A, B), with few pseudopores distally (Fig. 7B–D). Aperture circular (80–(84)–100 µm diameter), sometimes bicuspate. Laminar layer of internal wall formed by flattened, distally imbricated crystallites (Fig. 7E–F). Gonozooid not observed. Remarks. Two species of Mecynoecia have been recorded from Brazil, M. delicatula (Busk, 1875) and M. cf. smitti (Pergens, 1887) (see Marcus 1937; Buge 1979). Mecynoecia smitti differs from M. delicatula in having six to seven zooids around the branch circumference (cf. 8–10), longer peristomes (1500 µm cf. M. buski (Borg, 1944), was recorded from South America by Buge (1979). This has longer zooids (850–1400 µm), thicker branches (900–1200 µm) and larger apertures (150–190 µm) than M. cf. delicatula. Mecynoecia delicatula was previously described from São Paulo and Pernambuco states (Marcus 1937; Buge 1979). The Rio de Janeiro specimen is very similar to this material in all respects but, unfortunately, gonozooids are lacking, raising some doubts over the identity of the species (and even the genus). Ecology. Colonies found on artificial plates in a harbour, together with the cheilostome Bugula neritina (Linnaeus, 1753), in shallow (2 m) and calm water. Geographic distribution. Gulf of Mexico, Saint Helena, East Africa, Japan and Australia (Marcus 1937; Buge 1979). Brazil: São Paulo (Santos) and Pernambuco (Recife) States (Marcus 1937; Barbosa 1964; Buge 1979); Rio de Janeiro State (Baia da Guanabara, Rio de Janeiro city) (this study)., Published as part of Ramalho, L. V., Muricy, G. & Taylor, P. D., 2009, Cyclostomata (Bryozoa, Stenolaemata) from Rio de Janeiro State, Brazil, pp. 32-52 in Zootaxa 2057 on page 44, {"references":["Busk, G. (1875) Catalogue of marine Polyzoa in the collection of the British Museum, III. Cyclostomata. Trustees of the British Museum (Natural History), London, 39 + [2] pp., 34 pls.","Marcus, E. (1937) Briozoarios marinhos brasileiros I. Boletim da Faculdade de Philosofia, Sciencias e Letras, Universidade de Sao Paulo, Zoologia, 1, 3 - 224, 29 pls.","Buge, E. (1979) Bryozoaires Cyclostomes. Annales de l'Institut Oceanographique. Resultats Scientifiques des Campagnes de la Calypso, n. s., 11, 55: 207 - 252.","Borg, F. (1944) The stenolaematous Bryozoa. Further Zoological Results of The Swedish Antarctic Expedition 1901 - 1903, 3, 5: 1 - 276, 16 pls.","Barbosa, M. M. (1964) Catalogo das especies atuais de Bryozoa do Brasil com indicacoes bibliograficas. Publicacoes avulsas do Museu Nacional, 1 - 50."]}