Sertularella tronconica Galea, 2016

Galea, Horia R. & Schuchert, Peter, 2019, Some thecate hydroids (Cnidaria: Hydrozoa) from off New Caledonia collected during KANACONO and KANADEEP expeditions of the French Tropical Deep-Sea Benthos Program, European Journal of Taxonomy 562, pp. 1-70 : 41

Sertularella tronconica Galea, 2016

Figs 10F , 14 C–E

Sertularella tronconica Galea, 2016: 38 , figs 9Q–T, 10D.

Material examined

PACIFIC OCEAN • a 1.8 cm high colony with two (likely male) gonothecae, with almost only the perisarc left; off New Caledonia, stn CP4687; 22°29′ S, 167°30′ E; 256–268 m; 14 Aug. 2016; KANACONO leg.; MNHN-IK-2015-419 • a 1.7 cm high colony bearing an immature female gonotheca; off New Caledonia, stn DW4743; 22°52′ S, 167°34′ E; 380- 340 m; 23 Aug. 2016; KANACONO leg.; MNHN-IK-2015-426 • a 1.5 cm high colony with two female gonothecae; off New Caledonia, stn DW4744; 22°55′ S, 167°37′ E; 310– 290 m; 23 Aug. 2016; KANACONO leg., MHNG-INVE-120848 • a 1.5 cm high colony bearing one male gonotheca; off New Caledonia, stn DW4678; 22°51′ S, 167°34′ E; 308– 303 m; 13 Aug. 2016; KANACONO leg.; MNHN-IK-2015-464 .

Remarks

In material MNHN-IK-2015-426, the perisarc of the colony may be wavy to wrinkled in places, and the corrugations of the hydrothecae are more conspicuous, encompassing also their abaxial wall.

The hydrothecae in sample MNHN-IK-2015-419 display seven internal projections of the perisarc: four latero-adaxial, of which the two adaxial-most are the most prominent, one large abaxial, and two smaller latero-abaxial ( Fig. 14D ). Its gonothecae are believed to be male, owing their shape and size (ca 1680 µm long and 505 µm wide, only one measured), compared to those from the holotype (see Galea 2016); they are given off laterally from the middle of the internode on side opposite to hydrotheca but, soon after, they are shifted on to the anterior/posterior side of the colony; club-shaped, with slightly undulated walls, aperture distal, rounded, small (ca 100 µm wide), borne on rather short and narrow neck region.

Distribution

New Caledonia, Norfolk Ridge ( Galea 2016).

Figures

Fig. 10.A. DynamenaoppositaGalea, sp.nov.,holotype colony, MNHN-IK-2015-470.—B.Hydrallmania clavaformis Galea, sp. nov., holotype colony, MNHN-IK-2015-404. — C. Sertularella leiocarpoides Vervoort, 1993, one colony from sample MNHN-IK-2015-420. — D. Sertularella novaecaledoniae Vervoort, 1993, colony from sample MNHN-IK-2015-424. — E. Sertularella aff. sinensis Jäderholm, 1896, one colony from sample MNHN-IK-2015-418. — F. Sertularella tronconica Galea, 2016, colony from sample MNHN-IK-2015-419. Scale bars: A–B, D–E = 1 cm; C = 2 cm; F = 5 mm.

Fig. 14. A–B. Sertularella aff. sinensis Jäderholm, 1896, gonotheca in lateral view (A), apical view of gonotheca showing spines and central aperture (B), both from sample MNHN-IK-2015-418. — C–E. Sertularella tronconica Galea, 2015, hydrotheca (C), apical view of aperture showing internal, submarginal cusps (D), portion of colony with male gonotheca (E). Scale bars: A, E = 1 mm; B = 300 µm; C = 200 µm; D = 100 µm.