Hydroids (Cnidaria, Hydrozoa) of the Danish expedition to

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206 segment 0.8 mm long, with central hydrotheca and three nematothecae: one median inferior and two laterals. Intersegment of variable length, 0.4–0.6 mm, with a single nematotheca near its distal end. Hydrotheca cylindrical to campanulate, held at an angle of 30–40° to segment axis, length abcauline side 0.25–0.27 mm, diameter of opening 0.20–0.21 mm, margin sinuous, sometimes somewhat everted. Nematothecae movable. Lateral nematothecae on short, rounded apophysis. Nematothecae about 50 µm high, egg-shaped, two-chambered, upper chamber larger, walls incurved, abcauline and adcauline side with round emarginations, adcauline notch deeper and broader, reaching bottom of upper chamber. Hydranth small, fits into hydrotheca, about 16 tentacles. Male and female gonothecae present in same colony, often on same stem; if so, female gonothecae distal to male ones. Female gonotheca 0.5 mm long, egg-shaped, flattened, end truncated, when mature with large convex operculum, two nematothecae near base of gonotheca, pedicel of gonotheca with one separate segment attached to an apophysis originating below hydrothecae. Female gonothecae contain one egg only. Male gonotheca 0.4 mm, egg-shaped to oblong, distal end more pointed, operculum small, one nematotheca near base. Nematocysts: I, small tentacular capsule, 6 x 2 µm. – II, microbasic mastigophore in nematophores, (16–18) x (5) µm, almond-shaped, discharged shaft 0.7 times the capsule length. Remarks Antennella campanulaformis has recently been reported to occur in the north-eastern Atlantic (Ansín Agís, Ramil & Vervoort 2001), but Peña Cantero & Garcìa Carrascosa (2002) referred this population to a new species, Antennella ansini. The main character to distinguish A. ansini from A. campanulaformis is the occurrence of male and female gonothecae on separate stems. Distribution Australia, Seychelles, Indonesia (new record). Depth range 1–90 m. Type locality: Barwon Heads, Victoria, Australia. P. SCHUCHERT Antennella secundaria (Gmelin, 1791) Fig. 57. Sertularia secundaria Gmelin, 1791: 3856. Plumularia secundaria. – Pictet 1893: 53, pl. 2: fig. 26. Antennella secundaria. – Billard 1913: 8, fig. 1, pl. 1: figs 1– 3. – Stechow & Müller 1923: 473. – Mammen 1967: 296, fig. 93. – Millard & Bouillon 1973: 77, fig. 10E. – Millard 1975: 332, fig. 107F–L. – Vervoort & Vasseur 1977: 64, fig. 28. – Calder 1997: 29, fig. 7, synonymy. – Ryland & Gibbons 1991: 525, fig. 1. – Cornelius 1995b: 121, fig. 28 A–C, E–G, not D. – Hirohito 1995: 236, fig. 79a–c. – Schuchert 1997: 14, figs 3–4, synonymy. – Watson 1997: 522, fig. 6A–B. – Watson 2000: 45, fig. 34A–D. – Ansín Agís, Ramil & Vervoort 2001: 140, fig. 63, bib-liography. Material examined: Kei Islands Expedition stations: 65, male and female gonothecae present. – 67, on Diphasia digitalis, no gonothecae. – 68, on hydroids, no gonothecae. – 71, on sponge and stolons of other hydroids, no gonothecae. – 90, on hydroids, with female and male gonothecae, two samples. – 104, on hydroids, male and female gonothecae present. – 106, on hydroids, no gonothecae. – 107, on Bryozoa, no gonothecae. – 110, on hydroids, no gonothecae. – 111, only female gonothecae present. – Kei Islands Expedition, 5.12°S, 119.34°W, Ujungpandang, Samalon Island, 35 m, 28 Jun 1922, on Bivalvia, no gonothecae. – MNHG INVE 25024, Bay of Ambon, Moluccas, material of Pictet (1893, as Plumularia secundaria), no gonothecae. – MHNG INVE 32969, Banyuls-sur-Mer, France, Mediterranean, 15 May 2002, 62 m, on Protula sp., female gonothecae distal to male ones, living colony yellow-greenish. Description Colonies erect, shoots thread-like, lacking hydrocladia, mostly unbranched, fertile stems 0.8– 2 cm high. Stolons tubular, ramified. Basal part of stem without hydrothecae, stem above basal part heteromerously segmented by alternating oblique and transverse nodes. Main segments with hydrotheca and four nematothecae: one median inferior, two lateral of hydrotheca, and one axillary behind hydrotheca. Main segment quite short, hydrotheca project beyond transverse node. Intersegments mostly with two nematothecae, rarely some segments with three, length variable within and between stems. Hydrotheca cup-shaped, walls in side view rather straight, converging towards below, margin sinuous, opening forming an angle of 45 to 55° with the main axis, adcauline side adnate for half of its length or less, length of abcauline side 0.19–0.26 mm, opening diameter 0.20–0.23 mm. Nematothecae all two-chambered. Median inferior nematothecae with adcauline wall of upper
HYDROIDS OF THE DANISH EXPEDITION TO THE KEI ISLANDS Fig. 57. Antennella secundaria (Gmelin, 1791); A-D, station 104, colonies having short lateral nematothecae only; E–G, colonies with long lateral nematothecae, E & G, station 90, F, station 67. A. Part of stem with main- and intersegment. B. Two lateral nematothecae and apophysis, left one seen from inner side, right one in side view. C. Female and male gonothecae. D. Basal part of a branched stem. E. Part of stem, main- and intersegment, same scale as A. F. Size variation of lateral nematothecae of single stem, same scale as B. G. Gonothecae, same scale as C. – Scales: A, E = 0.1 mm; B, F = 50 µm; C, G = 0.2 mm; D = 0.5 mm. 207
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Family Solanderiidae HYDROIDS OF TH
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Hydroids (Cnidaria, Hydrozoa) of the Danish expedition to

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