Filellum magnificum Pena Cantero, Svoboda & Vervoort 2004

Filellum cf. magnificum Peña Cantero, Svoboda & Vervoort, 2004

(fig. 10A, table 8)

Filellum magnificum Peña Cantero, Svoboda & Vervoort, 2004: 2287, figs 2G–H, 5.

Material examined. Stn. CHL 02 —04.iii.2005, 13– 20 m, S58: sterile colonies, on polychaete tubes (MHNG INVE 53239).

Type locality. Weddell Sea, Antarctica.

Description. Stolons creeping on external surface of polychaete tubes, giving rise to irregularly-spaced hydrothecae. Hydrothecae consisting of a short basal portion, adnate to substratum, and a much longer free part (up to 2.5 mm high), sharply bending away from adnate part. Most hydrothecae with several widelyspaced renovations; hydrothecal aperture circular, rim even, though indistinctly everted. Upper side of adnate part provided with variable number of transverse striae. Coppinia absent.

Remarks. Although the present material is sterile, I have tentatively assigned it to F. magnificum based on the dimensions of the hydrothecae. The allied species F. antarcticum (Hartlaub, 1904) was also reported from Chile (Leloup 1974). Both are characterized by the varied length of the adnate part of hydrotheca, the varied angle between the free and adnate parts, and the presence of a few, long renovations of the rim. However, Peña Cantero et al. (2004) studied abundant material of both species and reached the conclusion that, despite these resemblances, and even in the absence of gonosome, the hydrothecae of F. magnificum are clearly distinguishable from those of F. antarcticum by their larger size, especially the larger diameter of the hydrothecal aperture.

Peña Cantero et al. (2004) found for F. antarcticum a maximum diameter of the hydrothecal rim of 130 µm, in both Vanhöffen’s (1910) specimens and the Polarstern material from Antarctica. Similarly, the fertile material studied by Millard (1975) from South Africa had hydrothecae with a maximum diameter at rim of 120 µm. The rim diameter in F. magnificum is comparatively larger, 169–208 µm (Peña Cantero et al. 2004).

The present material from Chile agrees with the description of F. magnificum by Peña Cantero et al. (2004), but our hydrothecae are somewhat larger than those from Antarctica (see table 8). El Beshbeeshy (1991) assigned infertile specimens of a Filellum species to F. antarcticum but, due to the large size of their hydrothecae, his material may therefore belong to F. magnificum.

World distribution. Antarctica (Peña Cantero et al., 2004).

Records from Chile. The present material was collected from Isla de Chiloé. This is the first record for Chile.