Antennella quadriaurita Ritchie, 1909

Galea, Horia R., 2010, Notes on a small collection of thecate hydroids (Cnidaria: Hydrozoa) from Tristan da Cunha, south Atlantic, Zootaxa 2336, pp. 1-18 : 11

Antennella quadriaurita Ritchie, 1909

( fig. 4 S)

Antennella quadriaurita Ritchie, 1909: 92 , fig. 9. – Schuchert, 1997: 29, fig. 9. – Vervoort & Watson, 2003: 344, fig. 83F–I.

Material examined. Stn. I10, 28.xi.2007: numerous sterile stems, up to 9 mm high, on sponge ( NHM 2009.24).

Remarks. The ahydrothecate segments in the present material are short and carry generally a single nematotheca, more rarely two. Following Millard (1977b), their length may vary considerably in correlation with the number of nematothecae they bear. Ritchie (1909) described 2–4 nematothecae in his type material, 3 being the most frequent number, while 1–4 are generally found upon inspection of numerous samples (Schuchert 1997).

The first pair of lateral nematothecae reaches slightly beyond the hydrothecal margin; the upper chamber is shallow, ca. 3–4 times shorter than the basal one; its adaxial wall is lowered, without cusp.

An important variation in the number and shape of the lateral nematothecae, as well as in the structure of the gonothecae was reported by Schuchert (1997), who did not exclude the involvement of a complex of species.

Distribution. The type material of this species was trawled (depth 183 m) by the S.Y. Scotia at Gough Island (Ritchie 1909). Additional records are from the tropical West Africa, Vema Seamount, South Africa, India, New Zealand, Japan, and Korea (Vervoort & Watson 2003).

Figures

FIGURE 4. A to E: Halecium? delicatulum (Coughtrey, 1876), morphotype 2 (continued) – gonotheca replacing a hydrotheca (A) or arising from stolon (B); mature female gonotheca with eggs (C); various shapes of female gonotheca (D); cross section through gonotheca (E). F and G: Amphisbetia minima (Thompson, 1879) – basal portion of stem (F); gonotheca (G). H to M: Sertularella sp. – basal part of stem (H); fragment of stem showing its straight shape (I) and mode of branching (J); two internodes (K); shape of hydrotheca (L); frontal views of two hydrothecal apertures showing 3 and 5 internal projections of perisarc (M). N and O: Sertularella gayi (Lamouroux, 1821) – fragment of monosiphonic part of stem with basal parts of three side branches (N); various shapes of the hydrotheca (O); P and R: Aglaophenia parvula Bale, 1882 – hydrotheca and detail of its margin (P); female corbula (R). S: Antennella quadriaurita Ritchie, 1909 – detail of stem in lateral (left) and frontal (right) views. Scale bars: 100 µm (M, P); 200 µm (F, S); 300 µm (A, B, E, K, L, O); 400 µm (J); 500 µm (C, D, G); 750 µm (H); 1 mm (I, R); 1.5 mm (N).