Watersipora subovoidea ( d’Orbigny, 1852 )

Ramalho, Laís V., Muricy, Guilherme & Taylor, Paul D., 2011, Taxonomic revision of some lepraliomorph cheilostome bryozoans (Bryozoa: Lepraliomorpha) from Rio de Janeiro State, Brazil, Journal of Natural History 45 (13 - 14), pp. 767-798 : 772-775

Watersipora subovoidea ( d’Orbigny, 1852)

( Figure 3 )

Cellepora subovoidea d’Orbigny 1852: 402 .

Lepralia cucullata Busk 1854: 81 , pl. 96, figs 4–6.

Watersipora subovoidea, Ryland et al. 2009: 54 , fig. 4C,D,G,H.

Material examined

Macaé: MNRJ-141, ship hull Valentin Shashin, 14 December 2002, collected by J.E.A. Gonçalves, depth 1.5 m. Arraial do Cabo : MNRJ-012, Forno Harbour, 11 October 2002, collected by L. V. Ramalho and D.C. Savi, depth 0.5 m. MNRJ-138, Forno Harbour, 20 August 2004, collected by L. V. Ramalho and D.C. Savi, depth 0.5 m. MNRJ-139, Forno Harbour, 7 July 2003, collected by L. V. Ramalho, depth 1.5 m. MNRJ-142, Farol beach – Cabo Frio Island , 4 April 2002, collected by L. V. Ramalho , depth 5 m. Rio de Janeiro City : MNRJ-140, Guanabara Bay (ship hull), 23 October 2002, collected by G. Muricy, depth 0.5 m. Sepetiba Harbour: MNRJ-666, Ilha Guaíba, June 2009, collected by J. Silva. Watersipora cucullata: NHM 1973.1.10, Gold Coast, Ghana ; NHM 1948.2.16.18, Santos (SP), Brazil, collected by E. Marcus. W. subtorquata: NHM 1980.1.12.3, Townsville Harbour , Queensland, Australia . W. subovoidea: NHM 1986.8.14.3, Florida , USA . NHM 1998.8.4.13, Port Vila Waterfront , Vanuatu .

Diagnosis (revised)

Colony encrusting, sometimes erect, unilamellar, black or brown, operculum having a median vertical stripe between two pale lateral areas (grey or white); zooids almost rectangular, disposed in quincunx, frontal wall covered by large pseudopores; no ovicells or avicularia.

Description

Colonies initially circular, from 0.5 to 1.4 cm in diameter, sometimes growing free from substrate forming unilamellar fronds. Central part of the colony dark, varying from brown to black, but colony border is sometimes pale in colour (grey, beige or orange) ( Figure 3A ).

Autozooids disposed in regular quincunx, oblong, almost rectangular, larger than wide (789 µm long, range 456–1038 µm by 390 µm wide, range 262–582 µm), divided from each other by a dark suture ( Figure 3B ). Frontal wall with scattered large pseudopores (29 µm, range 19–39 µm diameter), decreasing in abundance near the orifice ( Figure 3C ). Some zooids are wider and bud two narrower zooids to form new bifurcations. Primary orifice rounded (221 µm long, range 155–252 µm, by 234 µm wide, range 194–272 µm), with a sinus wider than deep (52 µm long, range 39– 68 µm, by 116 µm wide, range 58–136 µm), delimited by two prominent condyles ( Figure 3C ). Peristome variably developed around the primary orifice, often slightly elevated ( Figure 3B,C ). Operculum very dark (same colour as rest of autozooid), distal half with a vertical, median parallel-sided stripe showing two different colours: a black band and paler peripheral regions ( Figure 3D ).

Avicularia, spines and ovicells absent.

Habitat

Colonies collected on harbour piers, ships’ hulls, hydrozoans, bryozoans ( Zoobotryon verticillatum ) and Sargassum algae; 0–5 m deep.

Geographical distribution

World: Atlantic and Pacific Oceans ( Ryland et al. 2009). Brazil: Study area: Macaé, Arraial do Cabo (Forno Harbour and Farol Beach), Rio de Janeiro City (Guanabara Bay) and Sepetiba Harbour.

Remarks

The first record of the well-known fouling bryozoans Watersipora from the Rio de Janeiro coast was of W. subtorquata , described by d’Orbigny (1841–47) under the name Escharina torquata . Marcus (1937, 1938) subsequently described specimens from São Paulo and Espírito Santo states as W. cucullata . Winston (1982) included Marcus’s specimens in the synonymy of W. subovoidea , whereas Gordon (1989) included these same specimens in the synonymy of W. subtorquata and suggested that the name W. subovoidea should be discarded because this species cannot be recognized and the type locality is unknown. Taylor and Gordon (2002) figured d’Orbigny’s material from Rio de Janeiro of W. subtorquata , represented by specimen no. 13637 at the MNHN, Paris.

Recently, Ryland et al. (2009) reviewed W. subovoidea and W. subtorquata , showing two principal characters that distinguish these two species. Watersipora subovoidea has triangular, tooth-like condyles, located distomedially, and a strongly pigmented operculum with a parallel-sided dark central band; W. subtorquata has condyles in the form of narrow shoulders and an operculum with a dark biconcave band proximally. Ryland et al. (2009) added W. cucullata described by Marcus (1937, 1938) to the synonym of W. subtorquata , agreeing with Gordon (1989).

Comparing Rio de Janeiro specimens with the figures shown in Ryland et al. (2009), it is evident that these specimens are very similar to W. subovoidea in having triangular condyles and a parallel-sided dark band on the operculum. Therefore, we believe that it is important to review these characters in the species described by Marcus (1937, 1938).

Superfamily SCHIZOPORELLOIDEA Jullien, 1883 Family SCHIZOPORELLIDAE Jullien, 1883

Figures

Figure 3. Watersipora subovoidea (d’Orbigny, 1852). (A) General view of the colony; (B) autozooidal arrangement; (C) detail of autozooids (frontal view) with large pseudopores, slightly developed peristome and orifice with condyles and wide sinus. Scale bars: B: 400 µm; C: 100 µm. MNRJ-012; (D) Detail of operculum.