Sertularella blanconae El Beshbeeshy, 2011

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 : 263-265

Sertularella blanconae El Beshbeeshy, 2011

Figs 1C , 4A , C-H; Table 3

Sertularella blanconae El Beshbeeshy, 2011: 125 , fig. 39. – Galea & Schories, 2012a: 37, fig. 3P-S. – Galea et al., 2014: 32, pl. 3A, figs 6C, 7B.

Sertularella geodiae . – Blanco, 1976: 39, pl. 3 figs 7-8. – (?) Millard, 1977: 23, fig. 6E-F. – Blanco, 1994: 199 [non Sertularella geodiae Totton, 1930 ].

Sertularella conica . – Blanco, 1982: 154, figs 2-5. – Blanco,

1994: 198 [non Sertularella conica Allman, 1877 ].

Sertularella Gayi. – p.p. Jäderholm, 1903: 281 [non Sertularel-

la gayi ( Lamouroux, 1821) ].

(?) Sertularella gayi gayi . – Vervoort, 1972: 116, fig. 36A, B

[non Sertularella gayi ( Lamouroux, 1821) ].

(?) Sertularella gayi var. gayi . – Stepanjants, 1979: 87, pl. 16 fig. 4A, B [non Sertularella gayi ( Lamouroux, 1821) ].

Material examined: MHNG-INVE-86243; Chile, Región de Aysén, Isla Teresa, -44.95713° -73.79447°, 21.6 m, coll. HSFS, HF11, lot C234; 27.11.2011; a profuse, sterile colony with stems up to 16 cm high. – MHNG-INVE-86244; Chile, Región de Aysén, Isla Level, -44.47348° -7420472°, 25 m, coll. HSFS, HF11, lot C128; 24.11.2011; a ca. 7 cm high, fragmentary colony with male gonothecae. – HRG-0392; Chile, Región de Magallanes y de Antártica Chilena, Punta Arenas, Faro San Isidro, -53.78174° -70.97391°, 40 m, coll. D. Schories, lot #27; 04.01.2011; three sterile colony fragments 1.2-1.7 cm high. – HRG-0696; Chile, Región de Magallanes y de Antártica Chilena, Isla Santibañez, -54.91725° -68.36317°, 29 m, coll. HSFS, HF9, lot C247; 16.12.2010; very fragmented colony with lightly fascicled stems, some bearing spent gonothecae. – HRG-0694; Chile, Región de Aysén, southern exist of Canal Williams, -45.60103° -74.47819°, 8.9 m, coll. HSFS, HF11, lot C009; 19.11.2011; a profuse, ca. 8 cm high, sterile colony composed of several polysiphonic stems. – HRG- 1168; Chile, Región de los Lagos, southern Chiloé, Isla Yencouma, -43.419316° -74.081766°, 10 m, coll. HSFS, HF22, lot #65; 18.01.2015; two profuse, ca. 7 cm high, infertile colonies with polysiphonic stems. – SMNH 123866; Chile, Punta Arenas, coll. Swedish Tierra del Fuego Expedition 1895-1896; 05.12.1895; microslide ( Fig. 1C ) containing two sterile colony fragments, 2.0 and 2.3 cm high [material identified by Jäderholm (1903) as S. gayi ( Lamouroux, 1821) ].

Comparison material: HRG-1006; France, Roscoff, Trou aux Singes, 48.7961° -3.9708°, 72 m, leg. P. Schuchert; 08.09.2014; a 4.5 cm high, fertile colony of Sertularella gayi ( Lamouroux, 1821) . – HRG-0553; France, Brittany, depth unrecorded, coll. F. Ziemski; (day and month unavailable) 2011; a few infertile stems and fragments, up to 3.7 cm high, of S. gayi .

Description: Large, fan-shaped colonies, up to 16 cm high arising from broad, rhizoid stolon firmly attached to substrate; stems giving rise to irregularly-ramified side branches, up to the 3rd order; both stems and branches highly fascicled for most of their length; monosiphonic parts with regularly-pinnate structure. Both stems and branches divided into short, almost collinear internodes by means of weak, oblique constrictions of the perisarc. Each internode with a hydrotheca, or a hydrotheca and a short apophysis immediately below its base; apophyses alternate, arising generally every three hydrothecae. Hydrothecae biseriate, alternate, flask-shaped, adnate for about half their length; free adaxial wall slightly swollen and provided with 3-4 undulations, more prominent proximally, weaker distally, prolonged as inconspicuous transverse ridges at surface, not reaching the abaxial wall; the latter slightly concave to almost straight for most of its length, becoming convex below the aperture, surface smooth; aperture mounted on short, constricted neck region, expanding at rim; the latter with 4 pointed, equal, triangular cusps separated by moderately-deep, rounded embayments; margin occasionally renovated; 4 triangular opercular flaps with concentric striae; no intrathecal, submarginal cusps. Gonothecae (only male known) elongated-ovoid, lateral walls with up to 8 transverse ridges, of which 5-6 distalmost are complete and prominent, while the remaining ones become obsolete towards the base; aperture borne on the summit of a short neck region, and is flanked by 4 blunt-ended projections of perisarc.

Dimensions: See Table 3.

Remarks: The typical shape of a well-developed colony is illustrated in Galea et al. (2014, pl. 3A), and a male gonotheca in fig. 7B of the same paper. This species has been previously confused with S. gayi ( Lamouroux, 1821) by a number of authors (see synonymy). Their morphological differences are obvious by comparing Fig. 3A, C-H and Fig. 3B, I.

Distribution: Chile – Región de los Lagos [southern Chiloé (present study)]; Región de Aysén [Isla Level, Isla Teresa ( Galea et al., 2014); Canal Williams (present study)]; Región de Magallanes y de la Antártica Chilena [south of Peninsula Brunswick ( Galea & Schories, 2012a); Isla Dawson and Punta Arenas ( Jäderholm, 1903, as S. gayi ); Isla Santibañez (present study)]. Tierra del Fuego, no exact locality (? Stepanjants, 1979, as S. gayi var. gayi ). Argentina – Provincia del Chubut [(?) off Península Valdés ( Vervoort, 1972, as S. gayi gayi ), off Cabo Dos Bahías ( Blanco, 1982; 1994, both as S. conica )]; Provincia de Santa Cruz [Puerto Deseado ( Vervoort, 1972, as S. gayi gayi )]; Provincia de Tierra del Fuego, Antártida e Islas del Atlántico Sur [off the eastern entrance of the Magellan Strait ( Blanco, 1976; 1994, both as S. geodiae ); around Península Mitre ( Blanco, 1982; 1994, both as S. conica )]; numerous scattered records from the Argentine Shelf between ca. 40°-54° S ( El Beshbeeshy, 2011). Falkland Is. [(?) Stepanjants (1979, as S. gayi var. gayi ); off the N coast ( Blanco, 1982; 1994, both as S. conica ); off the SE coast ( El Beshbeeshy, 2011)]. (?) French Southern and Antarctic Lands – Crozet Shelf ( Millard, 1977, as S. geodiae ).

Figures

Fig. 1. (A, B) Sertularella allmani Hartlaub, 1901. Two holotype slides of Sertularia secunda Allman, 1888 (= Sertularia unilateralis Allman, 1888). (C) Sertularella blanconae El Beshbeeshy, 2011, material identified as S. gayi (Lamouroux, 1821) by Jäderholm (1903). (D) Sertularella clausa (Allman, 1888), holotype slide. (E, F) Sertularella contorta Kirchenpauer, 1884 identified as S. polyzonias (Linnaeus, 1758) by Jäderholm (1910) (E) and S. lagena Allman, 1876 by Stechow (1925) (F), respectively. (G) Slide material studied by Jäderholm (1905), containing S. contorta (colony on the left-hand side) and S. subantarctica Galea, sp. nov. (colony on right-hand side), the latter identified by him as S. allmani. (H-K) Sertularella gaudichaudi (Lamouroux, 1824). Slide materials identified as S. picta (Meyen, 1834) (H), S. antarctica Hartlaub, 1901 (I) and S. protecta Hartlaub, 1901 (J) by Jäderholm (1903); as S. protecta by Stechow, according to Rees & Thursfield (1965) (K).

Fig. 4. Sertularella blanconae El Beshbeeshy, 2011. Portion of colony from MHNG-INVE- 86243 (A), and comparison with sample HRG- 0553 of Sertularella gayi (Lamouroux, 1821) (B). Hydrothecae from HRG- 0696 (C), SMNH 123866 (D), Blanco (1976, as S. geodiae) (E), Blanco (1982, as S. conica) (F-H), and comparison with hydrotheca of S. gayi from sample HRG- 1006 (I). Scale bars: 200 μm (C-I), 1 mm (A, B).