Sertularella fuegonensis El Beshbeeshy 2011

Sertularella fuegonensis El Beshbeeshy, 2011

Fig. 8 C-I; Table 8

Sertularella fuegonensis El Beshbeeshy, 2011: 131, fig. 41. – (?) Vervoort & Watson, 2003: 161, fig. 37A-B. – Galea, 2007: 60, fig. 14D-F. – Galea et al., 2007c: 312, fig. 4A. Sertularella picta. – Vervoort, 1972: 114, fig. 35A-B [non Ser- tularella picta (Meyen, 1834)].

non Sertularella picta. – Vervoort, 1972: 113, figs 34, 35C [= Sertularella implexa (Allman, 1888)].

Material examined: ZMH C11884; FRV Walther Herwig, Stn. 280, Argentine Shelf, off Provincia de Santa Cruz, -51.50000° -68.50000°; 11.02.1971; a few infertile stems, up to 2 cm high, with remains of coenosarc. – MHNG-INVE-53441; Chile, Región de Magallanes y de la Antártica Chilena, Canal Vicuña, -52.16222° -73.27617°, 15-25 m, coll. HSFS, HF3, lot #142; 06.03.2006; several sterile colony fragments, up to 6 cm high. – MHNG-INVE-53447; Chile, Región de Magallanes y de la Antártica Chilena, Canal Vicuña, -52.16222° -73.27617°, 15 m, coll. HSFS, HF3, lot #143; 06.03.2006; a colony, ca. 6 cm high, and smaller fragments, all sterile.

Description: Colonies much branched, with no definite main stems, arising from rhizoid stolon. Both stems and branches divided into moderately-long, geniculate internodes by means of weak, oblique constrictions of the perisarc, sloping in alternate directions; each internode with a distally-placed hydrotheca, or a hydrotheca and a lateral apophysis immediately below its basis; apophyses given off irregularly every 1-10 hydrothecae; side branches, up to the 3rd order, generally alternate and coplanar. Hydrothecae biseriate, alternate, either coplanar or imperceptibly shifted on to one side of the stem; flask-shaped, adnate for 2/5th their adaxial length, constricted below aperture; free adaxial wall slightly sigmoid, surface either smooth or with 2-5 shallow wrinkles; 4 triangular, marginal cusps of unequal development (abaxial one the longest, adaxial one the shortest, and the two laterals of intermediate length), separated by rather deep, rounded embayments; occasionally 3 internal, submarginal cusps (2 lateroadaxial, 1 abaxial); renovations of the margin occur; 4 triangular opercular flaps. Gonothecae unknown.

Dimensions: See Table 8.

Remarks: The colony structure is illustrated by Galea (2007, fig. 14D). The free adaxial wall may be either smooth (Chilean material) or wrinkled (El Beshbeeshy, 2011), though colonies with hydrothecae exhibiting both situations may occur (e.g. Vervoort, 1972, fig. 35A, as S. picta). Intrathecal cusps occur variably among the hydrothecae of the same colony, with the abaxial one generally more conspicuous than the two latero-adaxial ones.

Distribution: Chile – Región de Magallanes y de la Antártica Chilena – Canal Vicuña (Galea, 2007). Argentina – scattered records from the Argentine Shelf between 41°-53° S (El Beshbeeshy, 2011); Provincia de Tierra del Fuego, Antártida e Islas del Atlántico Sur [off the northern coast of the tip of Península Mitre (Vervoort, 1972, as S. picta)]. (?) New Zealand (Vervoort & Watson, 2003).