Sabellaria nanella Chamberlin, 1919

Santos, André Souza Dos, Brasil, Ana Claudia Dos Santos & Christoffersen, Martin Lindsey, 2014, Sabellaria and Lygdamis (Polychaeta: Sabellariidae) from reefs off northeastern Brazil including a new species of Sabellaria, Zootaxa 3881 (2), pp. 125-144 : 131

Sabellaria nanella Chamberlin, 1919

Figures 3 A–C

Sabellaria nanella Chamberlin 1919: 261 , plate 2, figures 5–7; Johansson 1927: 98; Hartman 1938: 16, figures 8–10; 1944: 340, plate 30, figures 18–20; Rullier & Amoureux 1979: 188; Lana & Gruet 1989: 243; Kirtley 1994: 71, figures 4.26.1–4. 26. 2; Lana & Bremec 1994: 216, figures 1–2; Santos et al. 2011: 6, figure 4 (a–c); Lomonaco et al. 2011: figure 1.

Material examined. Total: 10 specimens. State of Rio Grande do Norte, Guamaré City: Project Caracterização Ambiental da Bacia Potiguar e Monitoramento Ambiental dos Emissários Submarinos do Polo Industrial de Guamaré . St. BPOT 20DG (05º0’0’’S 036º27’0’’W) [ POLY 00292]: 1 complete spec. 21/05/2004, 4.3 m, 4 mm long. St. BPOT 24DG (04º40’0’’ S 036º28.57’0’’W) POLY 00293]: 1 complete spec. 21/05/2004, 4.3 m, 3 mm long. St. BPOT 8DG (04º25’0’’S 036º23’0’’W) [ POLY 00294]: 1 complete spec. 21/05/2004, 5 m, 3 mm long. St. BPOT 10DG (05º3.1’0’’ S 036º29.77’ 0’’W) [ POLY 00295]: 1 complete spec. 27/05/2004, 5 m, 3 mm long. St. BPOT 25DG (05º20’0’’S 036º40’0’’W) [ POLY 00296]: 1 complete spec. 21/05/2004, 5 meters of depth, 3 mm long. St. E06DG (05º3.561’0’’ S 036º28.57’ 0’’W) [ POLY 00297]: 1 complete spec. 21/05/2004, 3 mm long. St. E10DG (05º3.561’0’’ S 036º24.5’ 0’’W) [ POLY 00298]: 1 complete spec. 21/05/2004, 6 m, 3 mm long. St. E15DG (05º3.561’0’’ S 036º28.57’ 0’’W) [ POLY 00299]: 1 complete spec. 21/05/2004, 10 m, 3 mm long. St. E22DG (05º0’0’’S 036º23’0’’W) [ POLY 00300]: 1 complete spec. 21/05/2004, 12 m, 3 mm long. St. E23DG (05º0’0’’ S 036º23.57’0’’W) [ POLY 00301]: 1 complete spec. 21/05/2004, 12.3 mm long.

Additional material examined. Brazil, Paraíba State. Total: 2 specimens. St. B10 (7°01´02´´S 34º47´55´´W) 1 complete spec. 03/2007 [CIPY-POLY 1025].St. B10 (7°01´02´´S 34º47´55´´W) 1 complete spec. 03/2007 [CIPY- POLY 1026].

Diagnosis. Outer paleae semi-cylindrical or chaliciform, concave, geniculate, with series of small lateral teeth on thecal margin; thecal margin curved towards interior of theca or straight, with one-two points ( Figure 3 A). Middle paleae short, strongly geniculate, square-shaped, with slight central depression ( Figure 3 B), inner series of paleae strongly geniculate, elongate, with anterior ends pointed ( Figure 3 C).

Remarks. Sabellaria nanella is an uncommon species because it is the only taxon that has this kind of organization of the opercular crown: outer palea chaliciform, medium paleae quadrangular, inner paleae geniculate. In 12 specimens examined no morphological variations were observed. The specimens examined have six pairs of nuchal hooks positioned after a short digitiform medium organ, as described in Santos et al. (2011). Kirtley (1994) considered the occurrence of S. nanella in Brazil to be a result of bioinvasion, possibly resulting from ballast water.

In the majority of cases, the occurrences of S. nanella along the Brazilian coast were associated with aggregates of Phragmatopoma caudata Morch, 1883 . The first report of this species along the Brazilian coast was in the State of Paraíba by Young (1989), in crevices of the coral Mussismilia hispida (Verrill 1901) from Quebra Quilha Reef, at Tambaú Beach, João Pessoa, Paraíba. In the present study the specimens were found from 4, 5– 12 m.

Sabellaria nanella was originally described from the Indo-West Pacific, but has also been reported from the eastern Pacific, from Ecuador ( Kirtley 1994), and along the Atlantic Ocean, from the coast of Ceará ( Kirtley 1994), Paraíba (Santos et al. 2011; Lomonaco et al. 2011), Bahia ( Lana & Bremec 1994), Espírito Santo, Rio de Janeiro ( Rullier & Amoureux 1979; Lana & Bremec 1994), São Paulo, and Uruguay ( Lana & Bremec 1994).

Figures

FIGURE 3. Sabellaria nanella Chamberlin, 1979 (POLY 292): (A) outer palea; (B) middle palea; (C) inner palea. Scale bars: A – C, 0.1 mm.