Lafoea dumosa ( Fleming, 1820 )

Peña Cantero, Álvaro L., 2021, Additions to knowledge of the biodiversity of benthic hydroids (Cnidaria: Hydrozoa) in the Balleny Islands (Antarctica), Zootaxa 4966 (3), pp. 321-336 : 325

Lafoea dumosa ( Fleming, 1820)

( Fig. 1D )

Material examined. TAN 0602/442, a 12-mm-high stem ( NIWA 144244).

Remarks. The present material agrees with that frequently reported in Antarctic waters. The hydrotheca, provided with a ringed pedicel, is roughly 700 µm high and 150 µm in diameter at aperture. The isorhizas are around 22 x 9 µm, coinciding with one of the two morphotypes found by Schuchert (2001) in relation to the size of the isorhizas.

Ecology and distribution. The material, which represents the first record of the species for the Balleny Islands, was collected at a depth of 140−150 m off Buckle Island.

Figures

FIGURE 1. Filellum antarcticum (Hartlaub, 1904): A, part of a coppinia showing gonothecal arrangement; B–C, distal part of gonothecae showing aperture (arrows). Lafoea dumosa (Fleming, 1820): D, hydrotheca and pedicel. Phialella belgicae (Hartlaub, 1904): E, hydrotheca and pedicel. Campanularia sp.: F, hydrotheca; G, distal part of pedicel, basal spherule and basal chamber with diaphragm. Antarctoscyphus elongatus (Jäderholm, 1904): H, internode with hydrotheca. Scale bar: 100 µm (B, C, G), 200 µm (A, D–F, H).