Reptadeonella bipartita

Almeida, Ana C. S., Souza, Facelucia B. C., Sanner, Joann & Vieira, Leandro M., 2015, Taxonomy of recent Adeonidae (Bryozoa, Cheilostomata) from Brazil, with the description of four new species, Zootaxa 4013 (3), pp. 348-368 : 353

Reptadeonella bipartita ( Canu & Bassler, 1928a)

( Figs 6–9 ; 37, Table 1 )

Adeona bipartita Canu & Bassler, 1928a: 37 , pl. 8, fig. 2. [ Brazil: Bahia]

Adeona bipartita: Marcus 1949: 25 , figs 37–39. [ Brazil: Espírito Santo]

Reptadeonella bipartita: Winston 1986: 24 , fig. 50. [ Puerto Rico; Jamaica]

Not Reptadeonella bipartita: Winston 2005: 46 , figs 121–122. [W. of Tortugas and Florida] Reptadeonella bipartita: Cheetham et al. 2007: 85 (?part), fig. 38.2. (?fig. 38.1) [Recent only: Jamaica; Puerto Rico and Brazil] Reptadeonella bipartita: Vieira et al. 2008: 24 . [ Brazil; checklist]

Reptadeonella bipartita: Almeida et al. 2015: 4 . [ Brazil: Bahia; checklist]

Material examined. Holotype: USNM 8567, Adeona bipartita, F. Canu & R. Bassler det., Bahia, Brazil, 49 m, coll. 1877 by Steamer Norseman. Additional specimens: MZUSP 1244–1246, Adeona bipartita, E. Marcus det., one dry and two balsam specimens, no locality on label, but presumably from Espírito Santo, Brazil [acc. Marcus (1949)]; UFBA 0 70, UFBA 266, UFBA 974, UFBA 977, UFBA 980, Camaçari, Bahia, Brazil, 11°21’– 12°37’S, 37°17’– 38°47’W, 22–26 m, coll. 2000–2008; UFBA 905–906, Todos os Santos Bay, Bahia, Brazil, 12º46'– 13º02' S, 38º29'– 38º33' W, 30–39 m, coll. 1997 by O. Alves; UFBA 991, Todos os Santos Bay, Bahia, Brazil, coll. 1976 by A. Bittencourt; UFPE 0 0 5, Jequiá da Praia, Alagoas, Brazil, 10°04' S, 36°02' W, coll. June 2002 by L.M. Vieira & M.D. Correia.

Description. Colony encrusting, multiserial, unilaminar, with dark cuticle. Zooids rhomboidal to polygonal, distally rounded, generally longer than wide, delimited by slightly raised lateral margins. Frontal shield heavily calcified, finely granular, marginally punctured by single (rarely double) row of 25–36 areolar pores; a pore frequently also on either side of rostral tip. Primary orifice approximately 15% of total length of frontal shield, transversely elliptical, sunken. Peristome not prominent, transversely elliptical and level with zooid surface, the margin slightly swollen, bordered by small nodules and distal marginal areolar pores. A thin transverse foramen, areolar in origin, between peristomial rim and avicularian rostral tip in neanic zooids, later becoming mostly or wholly concealed by secondary calcification. Suboral avicularium median on frontal shield, directed distally, longer than wide, extending from spiramen to peristome, the rostrum elongate-triangular, tiny condyles placed onethird length, no opesial cryptocystal shelf. No other frontal avicularia. Spiramen crescentic, set in a depression between avicularium and proximal zooidal margin. Gonozooids not recognized.

Remarks. Since the original description of R. bipartita , based on specimens from NE Brazil ( Canu & Bassler 1928a), there have been records of the species from the Caribbean and Florida ( Winston 1986; Winston 2005; Cheetham et al. 2007), including fossil specimens from Panama and Dominican Republic ( Cheetham et al. 1999) and SE Brazil ( Marcus 1949). The fossil specimens figured by Cheetham et al. (2007, fig. 38.1) are distinguished from the Brazilian specimens in having shorter avicularia, with the spiramen placed at midlength in the zooid. Cheetham et al. (2007) noted that the specimens described by Smitt (1873) as Porina violacea and studied by Winston (2005) are distinct from R. bipartita in having a continuous double row of marginal areolar pores (often single in R. bipartita , but some zooids may have double row, see Fig. 13 ) and recognizable gonozooids (not seen in R. bipartita ). Comparison of these specimens and Brazilian colonies also revealed differences in the size of avicularia (0.09–0.18 mm long in Floridan specimens vs 0.16–0.23 mm long in Brazilian specimens). All other records show a unique combination of characters—a single row of marginal areolar pores, suboral pores separated by the avicularian rostrum, straight (distally directed) avicularium and sunken crescentic spiramen.

Distribution. Caribbean: Jamaica and Puerto Rico; Atlantic: Brazil (Alagoas, Bahia and Espírito Santo); sublittoral.

Figures

FIGURES 6 – 9. Reptadeonella bipartita: 6, colony surface, general aspect; 7, group of autozooids showing paired subperistomial areolar pores, median avicularia and spiraminal openings (Figs 6, 7, USNM 8567, holotype, Bahia State, Brazil). 8, group of autozooids; 9, close-up of autozooids showing slit-like subperistomial areolar pores, avicularia and spiramina (Figs 8, 9, UFBA 266, Bahia State, Brazil). Scale bars: 6, 8 = 500 µm; 7, 9 = 200 µm.

FIGURES 13 – 14. Reptadeonella granulosa, MZUSP 739, holotype, São Paulo State, Brazil: 13, pluriserial encrusting colony; 14, close-up of autozooids and a gonozooid at the colony margin. Scale bars: 13 = 400 µm; 14 = 100 µm.