Halecium cf. antarcticum Vanhöffen, 1910

Soto, Joan J. & Peña, Álvaro L., 2019, Benthic hydroids (Cnidaria, Hydrozoa) from the Weddell Sea (Antarctica), Zootaxa 4570 (1), pp. 1-78 : 38-39

Halecium cf. antarcticum Vanhöffen, 1910

( Fig. 13a )

Material examined. ANT XV/3: 48-150, three stems, c. 70, 75 and 110 mm high; 48-237, some stems, up to 25 mm high, on Sc. nana ; 48-276, two stems, 40 and 60 mm high.

Remarks. The great resemblance between Halecium antarcticum and H. pseudodelicatulum makes both species almost indistinguishable in the absence of gonothecae (see Peña Cantero 2014b). The material examined here has been tentatively assigned to H. antarcticum based on the disposition of the hydrophore, pointing more outwards than in H. pseudodelicatulum ( Fig. 13a, j ).

Ecology and distribution. Species reported from 45 ( Watson 2008) to 1157 m ( Peña Cantero 2014a); present material was collected between 254 and 758 m. Species reported exclusively from East Antarctica ( Peña Cantero 2014b). Thus, if confirmed, present record will constitute the first evidence from the Weddell Sea as well as for West Antarctica, pointing to a circum-Antarctic distribution.

Figures

FIGURE 13. a Halecium cf. antarcticum: hydrophore and hydrotheca. b–d H. banzare: b hydrophore and hydrotheca; c male gonotheca; d colony. e H. exaggeratum: hydrophore and hydrotheca. f–g H. incertus: f hydrophore and hydrotheca; g gonotheca. h H. interpolatum: hydrophore and hydrotheca. i H. jaederholmi: hydrophore and hydrotheca. j–k H. pseudodelicatulum: j hydrophore and hydrotheca; k female gonotheca. l H. pseudoincertus: hydrophore and hydrotheca.