Arthropoma cecilii ( Audouin, 1826 ), 1929

Ramalho, Laís V., Taylor, Paul D., Moraes, Fernando Coreixas, Moura, Rodrigo, Amado-Filho, Gilberto M. & Bastos, Alex C., 2018, Bryozoan framework composition in the oddly shaped reefs from Abrolhos Bank, Brazil, southwestern Atlantic: taxonomy and ecology, Zootaxa 4483 (1), pp. 155-186 : 170-176

Arthropoma cecilii ( Audouin, 1826)

( Figs 5H , 7G )

Flustra cecilii Audouin, 1826: 239 .

Arthropoma cecilii: Canu & Bassler, 1929: 296 ; Marcus, 1937: 96, fig. 49; 1955: 297; Vieira et al., 2008: 31; Ramalho et al., 2011: 777, fig. 5; Bastos et al., 2018: table 1.

Material examined. Abrolhos Bank, Bahia State, Brazil: MNRJ-Bry1376, Parcel dos Abrolhos, 4 m depth, February 2014, col. R. Moura, G. Amado-Filho & A. Bastos.

Short description. Encrusting colonies, forming single layers ( Fig. 5H ); orange in colour with white ovicells when alive ( Fig. 7G ). Autozooids hexagonal to rectangular, frontal wall perforated by large circular pseudopores, except in a central area beneath the orifice. Ovicell hyperstomial.

Geographic distribution. Espírito Santo, Rio de Janeiro and São Paulo states ( Marcus 1937, 1955; Ramalho et al. 2011), Abrolhos Bank, Bahia State, Brazil ( Bastos et al. 2018; present study).

Remarks. Arthropoma cecilii has a worldwide distribution, although its apparent cosmopolitan nature deserves re-evaluation. In the present study, colonies were recorded only at 15 m deep, inside the cores and on the surface of the reefs; those on the external reef surfaces were alive and fertile.

Figures

FIGURE 5. Scanning electron micrographs of five bryozoan species. A, B. Stylopoma variabilis n. sp. A. Detail of a small fragment showing some zooids and an ooecium. B. Frontal view of one ooecium showing the crescent-shaped aperture and the fused and asymmetrical labellum. C–E. Stylopoma hastata n. sp. C. Detail of part of the colony showing zooids and different kinds of avicularia: small and triangular lateral oral avicularia, two large and spear-shaped interzooidal avicularia, and a giant elongated and curved avicularium. D. Detail of the distal part of a zooid showing the orifice with U-shaped sinus, small condyles, and a triangular lateral avicularium. E. Detail of a giant avicularium with curved, elongate rostrum. F. Hippaliosina imperfecta, detail of two zooids with a pair of elongate distal avicularia. G. Utinga castanea, detail of the colony showing zooids with different kinds of avicularia and ooecia with a pair of small avicularia. H. Arthropoma cecilii, detail of fertile and infertile zooids showing orifices, perforate frontal walls and smooth ooecia.

FIGURE 7. In situ underwater photographs of six bryozoan species recorded from Abrolhos Bank, Brazil. A, B. Steginoporella magnilabris. C. Reptadeonella bipartita. D. Celleporaria atlantica. E. Stylopoma variabilis n. sp. F. Utinga castanea. G. Arthropoma cecilii. Photos by Áthila Bertoncini/Rede Abrolhos.