(fig. 19D–J, table 33)
Sertularia setacea Linnaeus, 1758: 813.
Plumularia setacea: Hincks, 1868: 296, pl. 66 fig. 1; Clark, 1876: 261, pl. 61 figs 1–2; Nutting, 1900: 56, pl. 1 figs 1–4; Hartlaub, 1901: 374; Jäderholm, 1904a: 6; Stechow, 1919: 119; 1923: 226; Fraser, 1944: 352, pl. 76 fig. 342; Vervoort, 1946: 175, figs 27F, 73; 1966: 142, fig. 43; 1968: 64, fig. 29; Rees & Rowe, 1969: 22; Naumov, 1969: 503, fig. 354; Millard, 1973: 27, fig. 3; 1975: 399, fig. 124E–K; Hirohito, 1974: 41; Leloup, 1974: 49, fig. 43; Millard, 1975: 399, fig. 124E–K; Blanco, 1976: 54, pl. 7 figs 4–6; Hirohito, 1983: 70; Gili et al., 1989: 89, fig. 17B; Ramil & Vervoort, 1992: 191, fig. 47F–I; Cornelius, 1995b: 158, fig. 37; Hirohito, 1995 (English text): 278, fig. 95C–D; Medel & Vervoort, 1995: 56, fig. 24; Calder, 1997: 17, fig. 4; Ramil et al., 1998b: 37; Watson, 2000: 53, fig. 41A, B; Schuchert, 2000: 413; Ansín Agís et al., 2001: 238, fig. 91; Schuchert, 2001a: 131, fig. 111A; Peña Cantero & García Carrascosa, 2002: 117, fig. 21C–D; Vervoort & Watson, 2003: 398, figs 96G, 97A–G, 98A; Bouillon et al., 2004: 175, fig. 95A–E; Calder & Kirkendale, 2005: 482; Watson, 2005: 549, fig. 19A–D; Vervoort, 2006: 259; Galea & Leclère, 2007: 39, figs 1–3.
Plumularia diploptera Totton, 1930: 222, fig. 59A, B; Ralph, 1961b: 32, fig. 3F–J; Rees & Vervoort, 1987: 137, fig. 29; El Beshbeeshy, 1991: 271, fig. 68.
Material examined. Stn. CHL 01 —29.ii. 2005, 10 m, S1: six sterile plumes (normal form), up to 5.5 cm high, 3 slides (MHNG INVE 53154). Stn. COM 03 —21.i.2006, 17– 21 m, S154: two sterile fragments (normal form), 2.2 and 2.8 cm high, respectively. Stn. COM 04 —28.i.2006, 19– 23 m, HG107: several normal plumes overgrown by the epizootic form. Stn. COM 06 —26.i.2006, S95 (20–23 m): several normal stems, mainly with broken cladia and with only the perisarc left; HG070 (33 m): several normal plumes overgrown by the epizootic form. Stn. COM 07 —25.xii.2004, S53 (11.5 m): several normal, sterile plumes, up to 7 cm high, on mollusc shell, 3 slides (MHNG INVE 53228); S57 (22 m): five normal plumes, 4–12 cm high, some branched, one fertile; a small, sterile, epizootic colony present (MHNG INVE 53237); 09.iii.2005, 10– 25 m, S56: several normal, fertile plumes, up to 13 cm high; 20.i. 2006, 18 m, HG030 (18 m): several normal plumes overgrown by the epizootic form; 26.i. 2006, 21 m: several normal stems (MHNG INVE 38773) bearing epizootic colonies (MHNG INVE 38774). Stn. COM 09 —04.v.2005, S8 (12 m): six fertile stems, up to 6.5 cm high, on wood (MHNG INVE 53161); S9 (15 m): six sterile, normal plumes, up to 10.5 cm high (MHNG INVE 53162). Stn. COM10 —undated, 20 m, S52: seven sterile plumes, 2.0–5.5 cm high (MHNG INVE 53227). Stn. COM 13 – 21.ii. 2005, 25 m, S55: several sterile fragments, in poor condition; 22.ii.2005, 20– 30 m, S54: several plumes and fragments, up to 5.5 cm high, some with numerous gonothecae (MHNG INVE 53229). Stn. COM 14 —26.ii.2005, 10– 15 m, S60: one sterile plume, 5 cm high. Stn. CAD — 12.iii. 2006, 33 m, S136: two sterile plumes, 2.6 and 4.7 cm high, respectively, on dead gorgonian. Stn. CCA — 12.iii.2006, S123 (1–2 m): one young, sterile colony with stems about 1 cm high, on Chlorophyta (MHNG INVE 53383); S87 (28 m): several sterile fragments, up to 2 cm high, on gorgonian. Stn. AIN — 11.iii. 2006, 24 m, S117: several sterile stems up to 6.5 cm high, two of them branched (MHNG INVE 53373). Stn. CPI — 07.iii. 2006, 24 m, S122: several normal, sterile stems, up to 10 cm high, and smaller fragments, some bearing fertile colonies of the epizootic form (MHNG INVE 53382).
Type locality. “Habitat in Oceano” (Linnaeus, 1758). The name is based on Corallina setacea Ellis, 1755, described from Brighton and Whitstable, Great Britain (Calder, 1997).
Remarks. This species shows an enormous range of variability. For more details, see Calder (1997). Epizootic specimens were reported by several authors (Millard 1973, Ramil & Vervoort 1992, Ansín-Agís et al. 2001, Vervoort & Watson 2003). For a detailed description of the auto-epizootic forms from Chile, see Galea & Leclère (2007).
Hydroid epibionts. Bougainvillia pyramidata (Forbes & Goodsir, 1851); Hydractinia pacifica Hartlaub, 1905; Modeeria rotunda (Quoy & Gaimard, 1827); Filellum serratum (Clarke, 1879); Clytia linearis (Thornely, 1900).
World distribution. This species is cosmopolitan, except in purely Arctic and Antarctic waters (Calder 1997).
Records from Chile. Previous records of P. setacea are from the Guaitecas Islands (Jäderholm 1904a), Talcahuano, Calbuco (Hartlaub 1905) and from Tocopilla to Strait of Magellan (Leloup 1974). The present material was collected roughly between 41°49' S and 50°50' S.