Abietinella Levinsen, 1913

Marques, Antonio C., Peña Cantero, Alvaro L. & Migotto, Alvaro E., 2005, Redescription and systematic status of the Antarctic genus Abietinella Levinsen, 1913 (Lafoeidae, Hydrozoa, Cnidaria), Journal of Natural History 39 (18), pp. 1443-1455 : 1444

Genus Abietinella Levinsen, 1913

Abietinella Levinsen 1913, p 294 , Plate 4 Figures 21, 22a; Totton 1930, p 166; Vervoort 1972, p 82; Stepan’yants 1979, p 58; Rees and Vervoort 1987, p 45 –46.

Type species: Zygophylax operculata Jäderholm, 1903 , by subsequent designation by Totton (1930, p 166).

Diagnosis

Colonies erect, polysiphonic, arising from a creeping hydrorhiza. Hydrothecae campanulate and sinuous adcaudally, pedicellate; pedicel resting on cauline apophysis, each demarcated from pedicel basally by an annular perisarcal thickening; dish-shaped operculum attached to adcauline side of hydrothecal aperture. One nematotheca on each side of hydrothecal apophysis; nematothecae scattered on polysiphonic tubes of stem.

Gonophores fixed sporosacs. Gonothecae arranged in coppinia, placed on stem and main branches.

Remarks

The type species of the genus was subsequently selected by Totton (1930, p 166) as Z. operculata (and not by monotypy as considered by Rees and Vervoort 1987, p 45).

Although Rees and Vervoort (1987, p 46) assert that in the genus Abietinella the hydrocladia and hydrothecae are ‘‘rigorously in one plane’’, in A. operculata some hydrocladia are slightly rotated in relation to the plane of stem. This slight rotation should be considered, however, a plastic condition of the species, characteristic of deep waters.