Antennella sp.

(fig. 7K– O, table 13)

Material examined. Stn. 6: 23.03.2008 —numerous sterile colonies, up to 9 mm high, on Halimeda sp. and Caulerpa sp. (MHNG INVE 60984); 24.03.2008 —one sterile colony, ca. 9 mm high, on Caulerpa sp. Stn. 7: 25.03.2008 – numerous sterile stems, up to 6 mm high, on concretions and green algae.

Type locality. Plage de Pompière, Terre-de-Haut, Les Saintes, Guadeloupe.

Description. Stems up to 9 mm high, arising from creeping hydrorhiza. Basal part, of variable length, divided by means of 2–3 transverse nodes; last node oblique; segments with up to 8 frontal nematothecae in two parallel, alternate rows. Remainder of caulus heteromerously segmented. Hydrothecate segments, up to 13 per stem, with proximal oblique node and distal transverse node; with one hydrotheca in middle part and up to 4 nematothecae: one median inferior and a pair of laterals; the 2–3 basalmost hydrothecae often with a supra-axillar nematotheca, arising a short distance above axil, rim not surpassing free adcauline wall (fig. 7M). Intersegments, longer than segments, with 2 frontal nematothecae in a row parallel to stem axis. Hydrothecae nearly tubular, lateral walls parallel, rim circular, slightly everted. All nematothecae bithalamic; lateral nematothecae with circular rim, not scooped. Gonothecae not seen. Nematocysts: large microbasic mastigophores, in coenosarc and nematophores; microbasic mastigophores, in tentacles (for dimensions, see table 13).

Remarks. Antennella sp. comes very close to A. secundaria (Gmelin, 1791) . However, there is no axillar nematotheca in the former, but some of its basalmost hydrothecae bear one nematotheca a short distance above the axil. Additionally, the cnidome of the latter contains several egg-shaped capsules of unidentified type, apparently not present in the former. In the absence of gonothecae, no positive identification of the present material could be made. A morphometrical comparison between Antennella sp. and A. secundaria is given in table 13.

Distribution. The present material originates from Les Saintes.