Sertularella pauciramosa Galea & Schories, 2014

Horia R. Galea, Dirk Schories, Verena Häussermann & Günter Försterra, 2017, Taxonomic revision of the genus Sertularella (Cnidaria: Hydrozoa) from southern South America and the subantarctic, with descriptions of five new species, Revue suisse de Zoologie 124 (2), pp. 255-321 : 297

Sertularella pauciramosa Galea & Schories, 2014

Fig. 15F, G

Sertularella pauciramosa Galea & Schories, 2014 in Galea et al., 2014 : 35, pl. 3B, figs 6F & H, 7D.

Material examined: MHNG-INVE-86235; Chile, Región de Antofagasta, Taltal, -25.38333° -70.46667°, 22 m, coll. D. Schories, lot #17; 23.04.2012; a 6 cm high, male colony (holotype). – MHNG-INVE-86234; Chile, Región de Antofagasta, Taltal, Punta Morada, -25.36667° -70.45000°, 15 m, coll. D. Schories, lot #13; 20.04.2015; a 4 cm high, female colony (paratype).

Description: Colonies arising from creeping, branching, anastomosing stolon. Stems erect, up to 6 cm high, monosiphonic, slightly geniculate to almost straight; a varied number of annuli immediately above origin from stolon, followed by short, smooth, ahydrothecate part; remainder of caulus divided into short internodes by slightly marked to indistinct, oblique constrictions of the perisarc, slanting in alternate directions. Side branches, when present, arising irregularly from below the bases of stem hydrothecae, generally laterally (giving the colony a coplanar appearance), or occasionally slightly in front or the rear side of the stem; base of branch delimited from stem by a rather distinct node (no apophysis present); 1 st internode generally longer than subsequent ones. A hydrotheca confined to the distal end of each internode; biseriate, alternate, flask-shaped, slightly curving outwards; adnate for 2/5th their length; free adaxial wall smooth to wavy (in which case provided with 2-3 weak undulations); abaxial wall varied in shape, from slightly concave to straight, to rarely convex; aperture perpendicular to long axis of the theca, constricted below rim; 4 pointed, triangular cusps separated by shallow embayments; operculum 4-flapped. Gonothecae given off from below the bases of stem hydrothecae; ovoid, walls undulated to occasionally rather smooth; male and female similar in shape, though the former longer and slender; aperture mounted on short neck region provided with 3-4 distal projections of perisarc; female with ca. 20 oocytes.

Dimensions: Internodes 815-1140 μm long and 195- 230 μm wide at nodes. Hydrothecal free adaxial length 390-425 μm, adnate adaxial length 315-380 μm, abaxial length 635-690 μm, maximum width 335-365 μm, diameter at aperture 220-275 μm. Length of the female gonotheca 1490-1710 μm, and of the male 1710- 1965 μm; maximum width of the female gonotheca 660-805 μm, and of the male 660-730 μm.

Remarks: The typical shape of a colony of this species is illustrated in Galea et al. (2014, pl. 3B).

Distribution: Chile – Región de Antofagasta [around Taltal ( Galea et al., 2014)].