Hydroids (Cnidaria, Hydrozoa) of the Danish expedition to

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194 Gonotheca elongate amphora-shaped, walls smooth, length 2–2.2 mm, maximal diameter above middle 0.5–0.6 mm, terminal opening on a narrow tubular neck, length 0.2 mm. Distribution Moluccas, Kei Islands. Type locality: Moluccas, 3.450°S, 131.008°E, 567 m, on fine grey-yellow mud. So far only known from deeper waters (370–567 m). Family Thyroscyphidae Thyroscyphus bedoti Splettstösser, 1929 Fig. 4. Lytoscyphus junceus. – Pictet 1893: 37, pl. 2: figs 32–33. [Not Thyroscyphus junceus (Allman, 1876)] Thyroscyphus bedoti Splettstösser, 1929: 42, figs 36–38, new name. ?Thyroscypus macrocytharus. – Watson 2000: 37, fig. 29A. Type material examined: MHNG INVE 25030, as Lytoscyphus junceus, material described in Pictet (1893), type material of Thyroscyphus bedoti Splettstösser, 1929. Description Colony erect, up to 4 cm high, unbranched, without hydrocladia, with alternately oblique nodes, internodes smooth, of variable length, with subterminal apophysis for hydrothecae, apophysis demarcated from hydrotheca by node. Hydrothecae alternating, in two rows, in one plane. Pedicel of hydrotheca annulated or not. Mature shoots with numerous gonothecae of different developmental stages, almost every hydrotheca with one gonotheca below it Hydrotheca campanulate, radially symmetric to bilaterally symmetric, straight abcauline side and convex adcauline side, depth 1.1–1.2 mm, diameter at opening 0.6 mm, walls smooth; margin with 4 shallow cusps or almost even; operculum pyramidal with four flaps, mostly lost; diaphragm an oblique perisarcal ring, more developed on adcauline side. Hydranth with about 25 tentacles. Gonotheca 1.4 mm long, diameter 0.7 mm, cylindrical, tapering into pedicel below, distal half of gonotheca slightly undulated. P. SCHUCHERT Fig. 48. Thyroscyphus bedoti Splettstösser, 1929; after type material. A. Part of stem with hydrothecae and gonothecae of various developmental stages. B. Mature gonotheca, same scale as A. – Scale: A–B = 0.5 mm. Remarks Pictet (1893) allocated unbranched but mature colonies of a Thyroscyphus species to Lytoscyphus junceaus (Allman, 1876). Thyroscyphus junceus (Allman, 1874), an obvious synonym of T. fruticosus, forms large and branched plumes and it is unlikely that Pictet’s material belongs this species. In his detailed study of the Thyroscyphidae, Splettstösser (1929) therefore proposed a new name for Pictet’s species: Thyroscyphus bedoti. Thyroscyphus bedoti shows some resemblance to T. macrocyttarus (Lamouroux, 1824). This species has recently been re-described (Watson 1994) and synonymized with T. marginatus (Bale, 1884) (= T. balei Calder, 1983). Thyroscyphus macrocyttarus had been reported until recently only from temperate waters of southern and south-western Australia. Its colo-
HYDROIDS OF THE DANISH EXPEDITION TO THE KEI ISLANDS nies are characterized as occurring either as stolonal forms or as unbranched stems that have all their hydrothecae on one side only. The perisarc of its internodes are usually undulated. These characteristics separate it clearly from T. bedoti, which is a species of warm waters and which has two rows of hydrothecae. Watson (2000) allocated material from tropical waters near Darwin to T. macrocyttarus (as T. macrocytharus), although it had two rows of alternate hydrothecae and rather smooth internodes. Her material was growing on sponges. Due to these morphological, substrate, and biogeographic differences, I think that Watson’s material from Darwin could also belong to T. bedoti, although it has more pointed cusps and the hydrothecae are considerably smaller. Distribution Eastern Indonesia, ? northern Australia. Type locality: Batumera, Bay of Ambon, Moluccas, Indonesia; littoral zone, on coarse sand. Thyroscyphus fruticosus (Esper, 1793) Fig. 49. Spongia fruticosa Esper, 1793: 188. Thyroscyphus vitiensis Marktanner-Turneretscher, 1890: 210, pl. 3: fig. 10. – Gibbons & Ryland 1989: 427. Campanularia thyroscyphiformis Marktanner-Turneretscher, 1890: 206, pl. 3: fig. 4. – Rees & Vervoort 1987: 67. ?Campanularia juncea Allman, 1876: 260, pl. 11: figs 3–4. Campanularia juncea. – Thornely 1904: 113, text. figs 1–3, pl. 1: fig. 1a–b. Not Lytoscyphus junceus. – Pictet 1893: 37, pl. 2: figs 32–33 [= Thyroscyphus bedoti Splettstösser, 1929] Lytoscyphus fruticosus. – Stechow & Müller 1923: 465, pl. 27: fig. 6. Thyroscyphus fruticosus. – Splettstösser 1929: 7, figs 1–11, 13–27. – Vervoort 1941: 202. – Ralph 1961a: 754, fig. 1a. – ? Millard 1975: 323, fig. 104. – Gibbons & Ryland 1989: 425, fig. 40. – Watson 2000: 38, fig. 29D. Thyroscyphus ramosus. – Mammen 1965: 30, fig. 63. [Not T. ramosus Allman, 1877] Material examined: Kei Islands Expedition stations: 11, with gonothecae. – 19, with gonothecae. – 43. – 67, with gonothecae. – 86. – Kei Islands Expedition, Banda Islands, Lonthoir, 07 Jun 1922, with gonothecae. Description Colony erect, pinnate, 5–20 cm, stems often in 195 Fig. 49. Thyroscyphus fruticosus (Esper, 1793); A & C–D, station 19; B, station 11. A. Colony silhouette. B. Hydrotheca variant with marginal cusps and operculum. C. Two hydrothecae with smooth margin and a male gonotheca, same scale as B. D. Presumed female gonotheca, same scale as B. – Scales: A = 1 cm; B–D = 0.5 mm. dense clusters. Stem thick, stiff, monosiphonic, without nodes, with two lateral rows of hydrothecae, hydrothecae alternate and in one plane.
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