Symplectoscyphus patagonicus Galea & Schories, 2012, sp. nov.

Symplectoscyphus patagonicus sp. nov.

(pl. 4D, E, fig. 7A–F)

Material examined. Stn. FSI — 04.i.2011, S25 (40 m): a polysiphonic colony, 6 cm in height, devoid of its basal part, but including numerous smaller fragments, all fertile (part as MHNG-INVE-79641); S31 (40 m): holotype (MHNG-INVE-79666)—a polysiphonic colony, 9 cm high, and five fragments, 1.4–3.8 cm high, all bearing gonothecae; S33 (30 m): a few cladia and fragments of branches, up to 2.5 cm high, all sterile.

Description. Colonies coplanar, feather-like, arising from rather thick hydrorhizal plate. Stems polysiphonic nearly throughout, the number of accessory tubes diminishing gradually towards distal parts. Stems wavy to distinctly geniculate in lesser polysiphonic parts, each side branch introducing a new bend in the axis of stem. Basalmost parts of side branches equally polysiphonic, becoming monosiphonic distally. Branching pattern rather irregular basally, forming alternate side branches distally, each of these arising generally every three stem hydrothecae. Branches rebranching several times, so as to form up to 3rd order branches. Basal part of branches straight until bends are introduced through the formation of lower order branches (fig. 7A). Stems and branches divided into internodes, 625–930 µm long, 195–365 µm wide at nodes. Hydrothecae alternate on stem and branches, curved abcaudally, 345–415 µm wide in middle, adnate for half their length; abcauline side 485–595 µm long, with marked bend in middle region, free adcauline side 370–465 µm long, straight to slightly concave, distal end directed upwards; adnate adaxial side 420–465 µm long, terminating basally in a more or less prominent perisarc plug; three triangular cusps separated by moderately deep embayments; fenestrae occasionally present below hydrothecal bases; straight to convex line of desmocytes for the attachment of hydranths clearly visible in some hydrothecae; aperture 290–345 µm wide. Gonothecae on branches, arising from below hydrothecal bases, in frontal aspect of the colony; ovoid, 1870–2470 µm long, 920–1150 µm wide, with 3–5 distal, transverse ribs, slightly marked below; lower half gradually narrowing and ending in imperceptible pedicel; distal end truncate and provided with short tube (185–250 µm); the latter slightly constricted in middle region (150–165 µm), widening distally at aperture (190–210 µm).

Remarks. The colony shape and the mode of branching recall S. cumberlandicus (Jäderholm, 1905) and S. sofiae Peña Cantero et al., 2002. However, hydrothecae of these species are more tubular, more upwardly directed, adnate for a greater extent, their free adaxial wall is distinctly curved, and their gonothecae are more distinctly transversely grooved.

Etymology. Named after its area of distribution.

Distribution in Chile. Strait of Magellan.