Sertularella curta 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 : 272-273

Sertularella curta Galea & Schories, 2014

Fig. 7M, N

Sertularella curta Galea & Schories, 2014 in Galea et al., 2014 : 34, figs 6D-E, 7C.

Sertularella geniculata . – Leloup, 1974: 28, fig. 23 [non Sertularella geniculata Hincks, 1874 = Sertularella tenella ( Alder, 1857) ].

Material examined: MHNG-INVE-86236; Chile, Región de Antofagasta, Taltal, -25.38333° -70.51667°, 12-20 m, coll. D. Schories, lot #24; 24.04.2012; a 1.8 cm high, male colony (holotype). – MHNG- INVE-86237; Chile, Región de Antofagasta, Taltal, -25.38333° -70.51667°, 12-20 m, coll. D. Schories, lot #25; 22.04.2012; a 1.6 cm high, male colony (paratype).

Description: Colonies arising from creeping, branching stolon. Stems erect, up to 1.8 cm high, monosiphonic; basal part very short and ahydrothecate, either smooth or with up to 4 annuli; remainder of stem slightly geniculate, divided into short internodes by means of inconspicuous constrictions of the perisarc; a hydrotheca to the distal end of each internode. Side branches, when present (up to 3 per stem), short and arising irregularly from below a stem hydrotheca, either in front or the rear side of the colony; occasionally, the branches arise from within the stem hydrothecae; up to 2nd order branching observed. Hydrothecae biseriate, alternate, fusiform, adnate for about 2/3rd their length to the corresponding internode; free adaxial wall with about 3 transverse ridges prolonged abaxially; abaxial wall slightly concave, aperture expanding below rim, and perpendicular to long axis of the theca; margin with 4 equally-developed, triangular cusps separated by rounded, moderately-deep embayments; a 4-flapped operculum; 3 internal, submarginal cusps (2 latero-adaxial, 1 abaxial), not always noticeable. Gonothecae (only male known) originating from below the hydrothecal bases; ovoid-fusiform, walls with 6-7 transverse ridges, aperture surrounded by 4 perisarc projections.

Dimensions: Internodes 340-490 μm long and 170- 210 μm wide at nodes. Hydrothecal free adaxial length 345-380 μm, adnate adaxial length 230-270 μm, abaxial length 485-515 μm, maximum width 250-270 μm, diameter at aperture 210-230 μm. Male gonotheca 1440-1660 μm long and 575-620 μm wide.

Remarks: The gonotheca of this species is illustrated by Galea et al. (2014, fig. 7C).

Distribution: Chile – Región de Antofagasta [Bahía de Tocopilla ( Leloup, 1974, as S. geniculata ), Taltal ( Galea et al., 2014)].

Figures

Fig. 7. (A-H) Sertularella contorta Kirchenpauer, 1884 (continued). Mode of branching (A). Hydrothecae from NMSZ 1921.143.1351. D (B), SMNH 123884 (C) and ZSM 20050442 (D). Gonothecae from NMSZ 1921.143.1351. C (E), NMSZ 1921.143.1351. D (F), SMNH 123851 (G) and SMNH 123884 (H). (I-L) Sertularella cruzensis El Beshbeeshy, 2011. Colony fragments from holotype (I) and Vervoort (1972, as S. conica) (J). Hydrothecae from the same sources (K and L, respectively). (M, N) Sertularella curta Galea & Schories, 2014. Portion of stem with basal part of a side branch from MHNG-INVE- 86236 (M), and hydrotheca from HRG- 0721 (N). Scale bars: 200 μm (B-D, K, L, N), 500 μm (E-H), 1 mm (I, J, M).