Antennella

Galea, Horia R., 2013, New additions to the shallow-water hydroids (Cnidaria: Hydrozoa) of the French Lesser Antilles: Martinique, Zootaxa 3686 (1), pp. 1-50 : 32

Antennella sp.

(Fig. 7X –Z)

Material examined. Stn. 16, 11.ii.2012, 10– 15 m, M171: sterile colony on seaweed.

Description. Stems up to 4.5 mm high arising from creeping, branching hydrorhiza. Stems composed of an ahydrothecate basal part provided with 2–3 nematothecae in a frontal row; there is a proximal transverse constriction immediately above origin from stolon, occasionally another one placed distally; last node oblique. Stem above basal part heteromerously segmented into hydrothecate and ahydrothecate segments. Oblique nodes well-marked, transverse nodes faintly marked and incomplete, not reaching posterior side of the stem. Hydrothecate segments with proximal oblique node and distal transverse node; rather short, just enough to accommodate a hydrotheca and its associated nematothecae: a mesial one, situated below the base of hydrotheca, and a pair of laterals; distal part of segment ending a short distance above the axil; axillar nematotheca absent. Ahydrothecate segments with 2, rarely 3, frontal nematothecae in one row. Hydrotheca adnate for about half its length; walls slightly divergent; adnate one straight, abcauline one somewhat sigmoid, slightly flared at rim. All nematothecae bithalamic and movable. Gonothecae unknown. Cnidome: 1) seed-shaped microbasic heteronemes, very rare in the coenosarc; 2) small microbasic mastigophores, abundant in the tentacles, also present in the coenosarc; 3) larger capsules, presumably microbasic mastigophores, abundant in the nematophores, also scattered in the coenosarc.

Remarks. This species is readily distinguished from A. secundaria through its slightly marked heteromerous (nearly homomerous) segmentation of the stem, and the regular absence of an axillar nematotheca. Since the gonothecae remain undiscovered, no attempt to identify specifically this species is made.

Geographical distribution. Only known from Martinique.