Oswaldella garciacarrascosai Peña Cantero, Svoboda & Vervoort, 1997

Molinero, A. González & Peña Cantero, A. L., 2015, SEM study of species of Oswaldella Stechow, 1919 (Cnidaria, Hydrozoa, Kirchenpaueriidae), with an annotated checklist of the species of the genus, Zootaxa 4052 (4), pp. 401-441 : 409

Oswaldella garciacarrascosai Peña Cantero, Svoboda & Vervoort, 1997

( Figs 6 , 16 F, 17F, 19F)

Material examined. New Zealand Antarctic Expedition TAN0802: Stn 180, Tangaroa , 29 February 2008, 69.4318°S, 178.8195°W (off Cape Adare, Ross Sea,), 447–455 m ( NIWA 37896).

Description. Monosiphonic, unbranched stems, up to 70 mm high, divided into internodes. Angle between cauline apophyses and stem ca. 45°. Cauline apophyses with three nematophores, two axillary ones ( Fig. 6 B), each emerging through simple hole in perisarc, and a third nematophore emerging through ‘mamelon’ ( Fig. 6 A–B).

Hydrocladia unbranched ( Fig. 6 A) or bifurcated. Mesial-inferior nematophore emerging from strongly marked swelling at proximal third of internode ( Fig. 6 D); without nematotheca ( Fig. 6 C–D). Hydrotheca placed on middle of internode ( Fig. 6 A, C–D). Hydrotheca elongate. Adcauline wall mostly adnate, but with a distinct free portion ( Fig. 6 D). Abcauline wall almost straight, but slightly convex basally and typically with slight concavity just under hydrothecal rim ( Fig. 6 C–D). Hydrothecal aperture circular, perpendicular to long axis of internode, rim even ( Fig. 6 C–D).

Gonothecae fusiform. Male gonotheca with circular, subterminal aperture. Female gonotheca with wide, circular, distal opening ( Fig. 6 E).

Remarks. Until now only mature male gonothecae and immature female ones were known (cf. Peña Cantero et al. 1997); we have found mature female gonothecae ( Fig. 6 E).

Figures

FIGURE 6. Oswaldella garciacarrascosai Peña Cantero, Svoboda & Vervoort, 1997. A, hydrocladium showing hydrothecal arrangement; B, cauline apophysis with axillary nematophores and ‘ mamelon’; C – D, unforked hydrocladial internodes (C frontal view, D lateral view); E, gonotheca. Scale bar: 100 µm (A, C – E) and 20 µm (B).

FIGURE 16. Detail of the area from which mesial nematophore emerges. A, Oswaldella bifurca; B, Oswaldella delicata; C, Oswaldella elongata; D, Oswaldella erratum; E, Oswaldella frigida; F, Oswaldella garciacarrascosai; G, Oswaldella grandis; H, Oswaldella incognita; I, Oswaldella laertesi; J, Oswaldella niobae; K, Oswaldella rigida; L, Oswaldella shetlandica; M, Oswaldella stepanjantsae; N, Oswaldella vervoorti; O, Oswaldella sp. Scale bar: 20 µm (A – O).