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Tubularia sp. (Fig. 3F) ? Tubularia indivisa.— Vanhöffen, 1910: 278–279, fig. 3. Material examined. PROTEKER 2: Ile Suhm, several stems up to 50 mm high, with gonophores (MNHN IK – 2012–10432). PROTEKER 3: Ile Shum, several stems up to 45 mm high, with immature gonophores (MNHN IK –2012–10427). Description. Stems up to 50 mm high, whitish (yellowish at the most basal part), thin, diameter only slightly increasing distally. Perisarc smooth, soft; softer and corrugated in the 3-mm-long neck region. Transparent perisarc film starting just below the polyp. Distinct constriction between polyp and neck region. Hydrocaulus with one larger and nine smaller peripheral longitudinal canals. Polyp white (Fig. 3F), small, about 4 mm high and 3 mm wide. Polyp’s column relatively long. Hydranth with a whorl of about 20 aboral filiform tentacles (three or four originating from an inner position) and around 30 tentacles on hypostome column: ten or so oral tentacles, roughly in a circle; the remaining below, apparently in one level and partially fused to the polyp column for a significant proportion. Some polyps with about eight unbranched blastostyles in a whorl just above the aboral tentacles. Blastostyles of different length, the longest with up to ten gonophores (Fig. 3F): the two or three most basal ones incipient, the others much more developed. Gonophores up to 500 µm high and 450 µm in diameter, pedicel about 200 µm long. Cnidome (from MNHN IK–2012–10432) consisting of larger stenoteles [12.7±0.5 x 12.6±0.8 µm (n= 10), range 12–13.5 x 11–13.5 µm], smaller stenoteles [8.2±0.6 x 6.7±0.8 µm (n= 10), range 7.5–9.0 x 6.0–7.0 µm], haplonemes [12.8±0.9 x 4.6±0.6 µm (n= 10), range 12–14.5 x 4.0–5.5 µm], and desmonemes 6 x 5 µm. Remarks. The material from MNHN IK–2012–10432 is in poor condition and it is not possible to count accurately the number of tentacles, let alone the oral ones, but there seems to be also 20 aboral tentacles. The polyps from MNHN ID–2012–10427 are in much better condition, yet the gonophores are barely developed. The present material cannot be fully characterised due to the incomplete development of the gonophores. Studer (1879) described as Tubularia ? kerguelensis a tubulariid from Kerguelen with smooth stems up to 3 cm. The present material is clearly distinguishable from it because Studer’s species had fewer oral tentacles (eight) than aboral ones (16). His material also lacked gonophores. Vanhöffen (1910) reported Tubularia indivisa Linnaeus, 1758 from Kerguelen. The present material is morphologically close to Vanhöffen’s and could certainly be conspecific. According to him, the stems, 30–40 mm high, are smooth, without any annulation, and have clear longitudinal streaks. The polyp has 30–40 oral tentacles, arranged in several rows, and about 20 aboral ones. Even if the present material was conspecific with the material assigned to T. indivisa by Vanhöffen (1910), it is not clear whether it actually belongs to this species. According to Petersen (1990), T. indivisa has stems up to 200 mm long, with firm perisarc, and the polyps have 40–60 oral tentacles. As indicated above, the present material has much shorter stems with soft perisarc and the number of oral tentacles is distinctly smaller. Vanhöffen’s material lacked gonophores and the gonophores in the present material are not completely developed. Therefore, it would be necessary to study well-preserved, mature material from the area to confirm the identification. Ecology and distribution. Tubularia sp. was collected at depths from 14 to 43 m off Suhm Island., Published as part of Peña Cantero, Álvaro L., 2022, On a few benthic hydroids (Cnidaria, Hydrozoa) from the Kerguelen Islands (southern Indian Ocean), including the description of a new species, pp. 274-286 in Zootaxa 5165 (2) on pages 280-281, DOI: 10.11646/zootaxa.5165.2.7, http://zenodo.org/record/6831887, {"references":["Vanhoffen, E. (1910) Die Hydroiden der Deutschen Sudpolar-Expedition 1901 - 1903. Deutsche Sudpolar-Expedition 1901 - 1903, 11 (Zoology 3), 269 - 340.","Studer, T. (1879) Die Fauna von Kerguelensland. Verzeichniss der bis jetzt auf Kerguelensland beobachteten Thierspecies nebst kurzen Notizen uber ihr Vorkommen und ihre zoogeographischen Beziehungen. Archiv fur Naturgeschichte, 45, 104 - 141.","Linnaeus C. (1758) Systema naturae per regna tria natura, secundum classes, ordines, genera, species cum characteribus, differentiis, synonymis, locis. Editio decima, reformata. L. Salvii, Holmiae, 823 pp. https: // doi. org / 10.5962 / bhl. title. 542","Petersen, K. W. (1990) Evolution and taxonomy in capitate hydroids and medusae. Zoological Journal of the Linnean Society, 100, 101 - 231. https: // doi. org / 10.1111 / j. 1096 - 3642.1990. tb 01862. x"]}

Data on amphipod assemblage associated with sublittoral hydroids collected in the Kandalaksha Bay in the White Sea are presented in the paper. Eleven species of amphipods were found, among them only M. alderi (Stenothoidae) could be considered as specific symbionts for 3 species of sublittoral hydroid, namely H. falcate, S. mirabilis and T. larynx. Aquarium and in situ observation showed that adult females of M. alderi occupy hydrants and protect from other invading females, while males are moving between hydrants showing the absence of any strict territoriality. Probably, the species specifically associated with the habitat on the hydroids polyps allowing feed both on tissues of polyp/hydrant and catching floating particles. Females show no negative reaction to juveniles or males presenting on the same hydrants, and normally co-existed during all time of observations. The males during usually actively move inside the colony of hydroids T. larynx between hydrants and migrating to neighboring colonies showing no negative reaction to females or juvenile; they were numerously catch in plankton in September.

Two new species of hydroids, Eudendrium bleakneyi and Halecium praeparvum, are described from the Bay of Fundy. Fourteen others, Tubularia acadiae Petersen, 1990, Coryne pusilla Gaertner, 1774, Sarsia lovenii (M. Sars, 1846), Zanclea implexa (Alder, 1856), Corydendrium dispar Kramp, 1935, Rhizogeton fusiformis L. Agassiz, 1862, Bougainvillia muscus (Allman, 1863), Rhizorhagium roseum M. Sars, in G.O. Sars, 1874, Hydractinia symbiolongicarpus Buss & Yund, 1989, Eudendrium vaginatum Allman, 1863, Tiaropsis multicirrata (M. Sars, 1835), Obelia bidentata S.F. Clark, 1875, Halecium marsupiale Bergh, 1887, and Sertularella gigantea Hincks, 1874, are reported, with collection data, for the first time from the bay. All but Coryne pusilla, Rhizorhagium roseum, Eudendrium vaginatum, and Sertularella gigantea are also new to Atlantic Canada, while Zanclea implexa, Corydendrium dispar, and Halecium marsupiale are reported for the first time in the western North Atlantic. Two of those species, Hydractinia symbiolongicarpus and Obelia bidentata, are disjunct in distribution, with core populations occurring in warmer waters to the south of Cape Cod, Massachusetts. Both were discovered in Minas Basin, a hydrographically distinct embayment where surface water temperatures are much warmer during summer than in the perpetually cold lower Bay of Fundy. Rhizorhagium roseum and the subfamily Rhizorhagiinae are transferred from family Bougainvilliidae Lütken, 1850 to Pandeidae Haeckel, 1879. An annotated checklist of hydroids from the Fundy region, based on previously published reports and on new records of species, is added as an appendix. Included in the checklist are 43 species of anthoathecates and 75 species of leptothecates, referable to 30 families and 56 genera. Families with the most species were Sertulariidae (23), Haleciidae (13), Eudendriidae (11), and Obeliidae (10). Biogeographically, the aggregate hydroid fauna of the bay conforms with that occurring in other parts of the Western Atlantic Boreal Region. Halecium permodicum is proposed as a replacement name for Halecium minor Fraser, 1935, an invalid junior homonym of H. minor Pictet, 1893.

Tubularia acadiae Petersen, 1990 Figs. 1, 2, 4 a Tubularia acadiae Petersen, 1990: 198, figs. 39, 40. Tubularia couthouyi.��� Bleakney, 1972: 933.��� Bromley & Bleakney, 1985: 11, unnumbered figure [not Tubularia couthouyi L. Agassiz, 1860]. Type locality. USA: Massachusetts, Vineyard Haven (Petersen 1990: 198). Material examined. NS: Minas Basin, 26.iv.1967, 4��C, two solitary hydroids, up to 7 cm high, one with female and one with male gonophores, coll. J.S. Bleakney, ROMIZ B629. Description. Examined hydroids solitary, comprising fragments of three hydrocauli with hydranths. Hydrocauli unbranched, 5 cm and 7 cm long, maximum diameter 2 mm, mostly straight with a few irregular bends, incised by a few nodes marking points of growth and regeneration, gradually increasing in diameter from proximal part to distal end, each bearing a terminal hydranth above a bulbous neck; longitudinal peripheral canals about 7 in number, with one being wider than others, these canals sometimes branched and anastomosing. Perisarc on hydrorhiza thick except at distal end, extending over and appearing filmy around neck region, terminating at base of hydranth, smooth except for irregularly located nodes, golden- to amber-coloured in thick areas, thin and clear over neck region. Hydranths pear-shaped with slender hypostome, separated from bulbous neck region by a prominent circumferential groove, reaching 1.2 cm high from groove to tip of hypostome, maximum diameter 1.0 cm; tentacles occurring in aboral and oral whorls. Aboral tentacles about 55 in number, crowded, slightly staggered, laterally flattened at base, gradually tapering from proximal end to tip, about 1.3 mm long in preserved material, merging with ridges extending down over basal region of hydranth. Oral tentacles about 60 in number, tapering from proximal end to tip, to 5 mm long in preserved specimens, scattered within a narrow band around hypostome, bases adnate to hypostome and forming longitudinal ridges on it. Gonophores fixed sporosacs, borne on 10-12 thick blastostyles arising from hydranth just above aboral tentacles; blastostyles with unbranched main stem approximately as long as hydranth when fully developed, each one with several short, slender side branches bearing gonophores; sporosacs of both sexes borne on long pedicels. Female sporosacs oval; distal end with orifice surrounded by 4-5 laterally flattened, fin-shaped crests extending from one-third to half-way or more down outer wall of sporosac, commonly with 2-3 developing embryos or actinulae that do not entirely fill sporosac cavity; spadix long, sausage-shaped. Male sporosacs subspherical, lacking lateral crests, terminal appendages, and radial canals; spermatic tissue nearly filling sporosac cavity. Cnidome (Fig. 2) desmonemes (n = 10): 6.0���6.3 ��m long �� 3.6���4.0 ��m wide (undischarged) large haplonemes (n = 5): 10.4���11.1 ��m long �� 6.5���7.3 ��m wide (undischarged) small haplonemes (n = 3): 6.8���7.5 ��m long �� 4.0���4.3 ��m wide (undischarged) large stenoteles (n = 6): 12.5���13.2 ��m long �� 10.3���11.8 ��m wide (undischarged) small stenoteles (n = 10): 9.7���10.8 ��m long �� 7.0���7.9 ��m wide (undischarged) heteronemes (n = 10): 11.2���13.2 ��m long �� 3.8���4.3 ��m wide (undischarged) Remarks. Tubularia acadiae Petersen, 1990 was originally described from material collected at several locations near Woods Hole, Massachusetts, during the winter and early spring of 1964 (Petersen 1990). That account provides the only published record of the species, and only female colonies were mentioned. Petersen found the species again in 1970 while undertaking field work in Minas Basin, NS, during a visit to Acadia University (recorded as ��� Tubularia acadiae n.sp. ��� in a letter to Prof. J.S. Bleakney, received 24 January 1977). However, the latter record was never published, and it was not mentioned in his original description of the species. While no etymology of the specific name was given, it could refer either to Acadia University or to the geographic region known as Acadia (���Acadie��� in French) that was once a colony of France in northeastern North America. Both of these possibilities suggest a link to the Bay of Fundy region. Hydroids of T. acadiae are decidedly robust, and hydrocauli of the species are marked by nodes. These ���joints��� appear to be sites marking extension points of the hydrocaulus, and at least some likely represent locations where hydranths once existed. In Fraser���s (1944) key to species of Tubularia Linnaeus, 1758 from the Atlantic coast of North America, possession of a ���jointed stem��� was a prime character leading to identification of T. couthouyi L. Agassiz, 1860. In that regard, and in its large size as well, T. acadiae might easily be confounded for T. couthouyi. Indeed, records of T. couthouyi from Minas Basin (Bleakney 1972; Bromley & Bleakney 1985), the same location as material examined here, are taken to have been based on the morphologically similar T. acadiae. As for Tubularia couthouyi, it is close to and possibly conspecific with T. indivisa Linnaeus, 1758 (Petersen, 1990; Schuchert 2010). Tubularia acadiae differs from both T. couthouyi and T. indivisa in the morphology of its female gonophores. Those of T. acadiae have 4-5 fin-shaped crests at the distal end of the sporosac wall, while such crests are lacking in the other two species. Female sporosacs of T. regalis Boeck, 1860 have similar crests, but that species differs from T. acadiae in having blastostyles that lack side branches, sporosacs that either lack pedicels or occur on very short ones, and hydroids that grow as entwined clusters rather than as single polyps (Petersen 1990). The basal disc of T. regalis is also broadly lobed and dome-shaped rather than circular with a crenulated margin. Meanwhile, T. couthouyi has been distinguished from T. indivisa largely on the basis of its ���jointed��� stem. Such nodes and regular annulations are rare in T. indivisa (Schuchert 2010). It is unclear whether joints in the hydrocaulus of that species are formed as typical nodes or as points of hydranth regeneration. Hydroids assigned to T. couthouyi are also said to be more robust than those of the better-known Linnean species. According to Fraser (1944), hydrocauli of the species reach 15 cm high, while the diameter across hydranths and extended tentacles sometimes attains 3���4 cm. He reported that hydranths of T. couthouyi bore as many as 30-40 aboral tentacles and 50 oral tentacles. Yet these measurements and tentacle numbers scarcely if at all exceed those reported in T. indivisa (see Schuchert, 2010). Another difference, according to Fraser (1947a: 147), is the existence in T. couthouyi of a series of deep annulations on the hydrocaulus immediately beneath the hydranth. However, these structures are not mentioned or illustrated in the original description of the species (L. Agassiz 1862). Finally, Agassiz believed that his species differed from T. indivisa in being an inhabitant of brackish waters, although T. indivisa has been found in salinities as low as 18��� (Sch��nborn et al. 1993). Male gonophores of T. acadiae, previously undescribed, were observed in examined material (ROMIZ B629) and have been described herein. They are much as in T. indivisa and T. regalis, although perhaps somewhat more nearly round in shape than in those species (Fig. 1). Also previously undescribed is the cnidome of the species, illustrated here (Fig. 2). Phylogenetic studies by Nawrocki et al. (2013) support the hypothesis that Tubulariidae Fleming, 1828 is monophyletic. Three lineages were recognized within the family, with one of them including the genera Tubularia and Hybocodon L. Agassiz, 1862, another including Ectopleura L. Agassiz, 1862, and a third comprising Ralpharia Watson, 1980 and Zyzzyzus Stechow, 1921a. Hydroids assigned to Tubularia, Hybocodon, and Ectopleura are quite similar in morphology. All three genera have been reported in the Bay of Fundy, although the sole representative of Hybocodon (H. prolifer L. Agassiz, 1860) is known there only from its medusa stage (Fish & Johnson 1937). Several characters distinguish these three genera (Table 1). Species of Tubularia and Hybocodon are held to differ from those of Ectopleura in being solitary rather than colonial. Cornelius (1995a) noted that current definitions of the term ���colony��� do not adequately differentiate the various types of colonies that are now known to exist in hydrozoans. Within the group, a colony is usually understood to constitute an assemblage of interconnected polypoid and/or medusoid individuals derived asexually from a single larval stage (Cornelius 1995a; Bouillon et al. 2006; Nawrocki & Cartwright 2012; Brinckmann-Voss & Calder 2013). However, colony formation of a distinctly different kind is known to occur in Ectopleura larynx (Ellis & Solander, 1786). Nawrocki & Cartwright (2012) discovered that colonies in that species were formed through the fusion of sexually generated polyps rather than by asexual propagation. Tubularia acadiae has been reported at depths from extreme low water spring (Bleakney 1972, as T. couthouyi) to 30 m (Petersen 1990). Type material, comprising 31 specimens reaching a maximum of 8 cm high, was collected on stones and shells in the area around Woods Hole, Massachusetts. It is a species of boreal waters, having been found during winter and spring both at its type locality and in Minas Basin. Recorded distribution. Bay of Fundy: recorded for the first time as Tubularia acadiae. Kingsport, Minas Basin, NS (Bleakney 1972, as Tubularia couthouyi L. Agassiz, 1860); Minas Basin, NS (Bromley & Bleakney 1985, as T. couthouyi). Eastern North America: Minas Basin, NS (reported herein) to the Woods Hole area, Massachusetts (Petersen 1990). Elsewhere: as above., Published as part of Calder, Dale R., 2017, Additions to the hydroids (Cnidaria, Hydrozoa) of the Bay of Fundy, northeastern North America, with a checklist of species reported from the region, pp. 1-86 in Zootaxa 4256 (1) on pages 6-9, DOI: 10.5281/zenodo.556851, {"references":["Petersen, K. W. (1990) Evolution and taxonomy in capitate hydroids and medusae (Cnidaria: Hydrozoa). Zoological Journal of the Linnean Society, 100, 101 - 231.","Bleakney, J. S. (1972) Ecological implications of annual variation in tidal extremes. Ecology, 53, 933 - 938. https: // doi. org / 10.2307 / 1934311","Bromley, J. E. C. & Bleakney, J. S. (1985) Keys to the fauna and flora of Minas Basin. National Research Council of Canada, Ottawa, 366 pp.","Agassiz, L. (1860) Contributions to the natural history of the United States of America. Vol. III. Little, Brown & Company, Boston, 301 pp.","Linnaeus, C. (1758) Systema naturae per regna tria naturae, secundum classes, ordines, genera, species cum characteribus, differentiis, synonymis, locis. Editio decima, reformata. Laurentii Salvii, Holmiae, 823 pp.","Boeck, C. (1860) Omhandlede en Tubularie fra Belsund paa Spitzbergen - Tubularia regalis. Forhandlinger i Videnskabs- Selskabet i Christiania, 1859, 114 - 117.","Fraser, C. M. (1944) Hydroids of the Atlantic coast of North America. University of Toronto Press, Toronto, 451 pp.","Fraser, C. M. (1947 a) Distribution and relationship in American hydroids. University of Toronto Press, Toronto, 464 pp. [although dated \" 1946 \" on the title page, this book was not published until February 1947]","Agassiz, L. (1862) Contributions to the natural history of the United States of America. Vol. IV. Little, Brown & Company, Boston, 380 pp.","Schonborn, C., Arndt, E. A. & Gosselck, F. (1993) Bestimmungsschlussel der benthischen Hydrozoen der Ostsee. Mitteilungen aus dem Zoologischen Museum in Berlin, 69, 201 - 253.","Nawrocki, A. M., Collins, A. G., Hirano, Y. M., Schuchert, P. & Cartwright, P. (2013) Phylogenetic placement of Hydra and relationships within Aplanulata (Cnidaria: Hydrozoa). Molecular Phylogenetics and Evolution, 67, 60 - 71. https: // doi. org / 10.1016 / j. ympev. 2012.12.016","Fleming, J. (1828) A history of British animals, exhibiting the descriptive characters and systematical arrangement of the genera and species of quadrupeds, birds, reptiles, fishes, Mollusca, and Radiata of the United Kingdom. Bell & Bradfute, Edinburgh, 565 pp.","Watson, J. E. (1980) The identity of two tubularian hydroids from Australia with a description and observations on the reproduction of Ralpharia magnifica gen. et sp. nov. Memoirs of the National Museum of Victoria, 41, 53 - 63.","Stechow, E. (1921 a) Neue Genera und Species von Hydrozoen und anderen Evertebraten. Archiv fur Naturgeschichte, Abteilung A, 3, Heft, 87, 248 - 265.","Fish, C. J. & Johnson, M. W. (1937) The biology of the zooplankton population in the Bay of Fundy and Gulf of Maine with special reference to production and distribution. Journal of the Biological Board of Canada, 3, 189 - 322. https: // doi. org / 10.1139 / f 37 - 015","Cornelius, P. F. S. (1995 a) North-west European thecate hydroids and their medusae. Part 1. Introduction, Laodiceidae to Haleciidae. Synopses of the British Fauna, New Series, 50, 347 pp.","Bouillon, J., Gravili, C., Pages, F., Gili, J. - M. & Boero, F. (2006) An introduction to Hydrozoa. Memoires du Museum National d'Histoire Naturelle, 194, 1 - 591.","Nawrocki, A. M. & Cartwright, P. (2012) A novel mode of colony formation in a hydrozoan through fusion of sexually generated individuals. Current Biology, 22, 825 - 829.","Brinckmann-Voss, A. & Calder, D. R. (2013) Zyzzyzus rubusidaeus (Cnidaria, Hydrozoa, Tubulariidae), a new species of anthoathecate hydroid from the coast of British Columbia, Canada. Zootaxa, 3666 (3), 389 - 397. https: // doi. org / 10.11646 / zootaxa. 3666.3.9","Ellis, J. & Solander, D. (1786) The natural history of many curious and uncommon zoophytes, collected from various parts of the globe by the late John Ellis … Systematically arranged and described by the late Daniel Solander. Benjamin White & Son, and Peter Elmsly, London, 206 pp."]}

Tubularia longstaffi Hickson & Gravely, 1907 (Figs 6–8; Table 4) Tubularia longstaffi Hickson & Gravely, 1907: 14 –15, pl. 2 fig. 11. Material examined. Stn 71, 25 stems up to 55 mm high (NIWA 117482); Stn 72, six stems up to 60 mm high, without polyps (NIWA 117483); Stn 104, single stem 78 mm high, with gonophores (MNCN 2.03/531); Stn 105, 20 stems up to 110 mm high, most without polyps (MNCN 2.03/532); Stn 150, one stem 140 mm high (NIWA 117484); Stn 178, 19 stems up to 60 mm high, some without polyps, with gonophores (NIWA 117485); Stn 198, one stem 21 mm long, without polyp (NIWA 117486). Other material examined. Tubularia longstaffi Hickson & Gravely, 1907 (type material, Natural History Museum, London, Coel no. 1907.8.20.9): McMurdo Bay, Ross Sea, No. 6 hole, April 8th, 1903, 227 m. Description. Stem up to 140 mm high. Perisarc tube reaching base of polyp, yellow, transversally ringed (Fig. 6 A), relatively firm, becoming weak and translucent distally (Fig. 6 B). Tube diameter increasing distally, from ca. 250 µm basally to 1 mm distally. Coenosarc attached to inner side of tube, with about 14 similar longitudinal lines. Polyps 2–5 mm high and 2–5 mm in maximum diameter, with aboral crown of 11 to 20 filiform tentacles (about 5 mm in length) (Fig. 6 C), and oral crown of 30–32 filiform tentacles (ca. 1.5 mm in length) (Fig. 6 D). Fertile polyps with ca. ten unbranched blastostyles (ca. 1150 µm in length), each with ca. 17 gonophores (largest ca. 400 x 250 µm) (Fig. 6 B–D). Cnidome (Fig. 7) consisting of stenoteles in two size classes, two types of haplonemes and desmonemes. Measurements (in µm). Stn 178: Cnidome: stenoteles I [range 9.0–11.0 x 7.0–8.0, mean 10.0±0.7 x 7.7±0.4 (n=10); ratio, range 1.2–1.5, mean 1.3±0.1 (n=10)]; stenoteles II [range 11.5 x 11]; rounded haplonemes [range 13.0–15.0 x 9.0–11.0]; tear-shaped haplonemes [range 14.0–16.0 x 4.5–5.5, mean 14.4±0.6 x 5.1±0.3 (n=9); ratio, range 2.6–3.2, mean 2.9±0.2 (n=9)]; desmonemes [range 6.0 x 4.0]. Stn 150: Cnidome: stenoteles I, abundant [range 10.0–11.5 x 7.0–8.5, mean 10.4±0.5 x 7.6±0.5 (n=7); ratio, range 1.3–1.4, mean 1.4±0.1 (n=7)]; stenoteles II, scarce [range 13.5–14.0 x 12.0–13.0]; rounded haplonemes [range 14.0–16.0 x 9.5–11.0, mean 15.1±0.8 x 10.3±0.6 (n=6); ratio, range 1.4–1.6, mean 1.5±0.1 (n=6)]; tear-shaped haplonemes [range 13.5–17.0 x 4.5–6.0, mean 15.5±1.0 x 5.2±0.5 (n=7); ratio, range 2.3–3.4, mean 3.0±0.3 (n=7)]. Description (Type of Tubularia longstaffi). Stem broken into three parts: basal part corresponding to hydrorhizal stolon; 44 mm long middle part corresponding to basal part of stem (Fig. 8 A); distal part with hydranth (Fig. 8 C). Diameter of stem distinctly increasing distally, from ca. 0.5 mm basally to ca. 1.5 mm distally. Stem perisarc yellowish, transversally striated (Fig. 8 B). Stem with ca. 14 longitudinal coenosarc strands. Polyp (Fig. 8 C) with oral crown of over 50 filiform tentacles, aboral whorl with 25 filiform tentacles, ca. 13 mm long, merged basally. Blastostyles unbranched, with up to 23 well developed gonophores (Fig. 8 D–F), except by incipient grouped gonophores at base of blastostyles. Cnidome consisting of stenoteles, apparently in two size classes, two types of haplonemes and desmonemes. Measurements (in µm). Cnidome: stenoteles I [range 10.0–10.5 x 7.0–8.0, mean 10.1±0.2 x 7.5±0.2 (n=10); ratio, range 1.3–1.4, mean 1.3±0.0 (n=10)]; stenoteles II [range 11.0–14.0 x 10.0–12.5, mean 12.7±1.2 x 11.5±1.1 (n=3); ratio, range 1.0–1.2, mean 1.1±0.1 (n=3)]; rounded haplonemes [range 15.0–16.0 x 10.5–12.0, mean 15.6±0.5 x 11.3±0.5 (n=10); ratio, range 1.3–1.5, mean 1.4±0.1 (n=10)]; tear-shaped haplonemes [range 14.5–16.0 x 5.0–6.5, mean 15.4±0.5 x 5.7±0.5 (n=10); ratio, range 2.5–3.0, mean 2.7±0.2 (n=10)]; desmonemes [range 6.5 x 4.5]. Remarks. After examining the type material of Tubularia longstaffi, I have no doubt that the BioRoss 2004 material belongs to that species, by their similar stem structure and cnidome. Diameter of the stem distinctly increases distally and the perisarc is yellowish and transversally striated. In relation to the cnidome, both have stenoteles, in two size classes, two types of haplonemes and desmonemes, all of similar size (cf. Table 4). The only difference is the slightly smaller number of oral tentacles in the present material (type material of T. longstaffi with over 50 tentacles). Tubularia Tubularia ralphii Tubularia Tubularia Tubularia hodgsoni (Hickson & longstaffi longstaffi longstaffi (Type) Gravely’ material) (Type) Stn 150 Stn 178 Smaller Range 8.5–10.0 x 10.0 x 10.0–10.5 x 10.0–11.5 x 7.0– 9.0–11.0 x stenoteles 7.0–7.5 7.5–8.0 7.0–8.0 8.5 7.0–8.0 Mean 9.3±0.5 x 10.0±0.0 x 10.1±0.2 x 10.4±0.5 x 10.0±0.7 x 7.2±0.2 (n=10) 7.8±0.2 (n=5) 7.5±0.2 (n=10) 7.6±0.5 (n=7) 7.7±0.4 (n=10) Rounded Range 14.0–15.5 x 14.5–15.5 x 15.0–16.0 x 14.0–16.0 x 9.5– 13.0–15.0 x haplonemes 10.0–13.0 10.5–11.5 10.5–12.0 11.0 9.0–11.0 Mean 14.8±0.5 x 15.0±0.3 x 15.6±0.5 x 15.1±0.8 x - 11.5±0.9 (n=10) 11.5±0.9 (n=7) 11.3±0.5 (n=10) 10.3±0.6 (n=6) Tear-shaped Range 13.5–15.0 x 13.0–14.0 x 14.5–16.0 x 13.5–17.0 x 4.5– 14.0–16.0 x haplonemes 4.5–6.0 5.0–5.5 5.0–6.5 6.0 4.5–5.5 Mean 14.3±0.6 x 13.7±0.4 x 15.4±0.5 x 15.5±1.0 14.4±0.6 x 5.2±0.5 (n=10) 5.1±0.2 (n=5) 5.7±0.5 (n=10) x 5.2±0.5 (n=7) 5.1±0.3 (n=9) Larger Range - - 11.0–14.0 x 13.5–14.0 x 12.0– 11.5 x 11 stenoteles 10.0–12.5 13.0 Mean - - 12.7±1.2 x - - 11.5±1.1 (n=3) Desmonemes 6.0–6.5 x 6.0 x 4.5 6.5 x 4.5 - 6.0 x 4.0 4.0–4.5 I have also studied the type material of Tubularia hodgsoni and the material assigned to Tubularia ralphii by Hickson & Gravely (1907). Both agree with T. longstaffi, and the material studied here, in the structure of the stem, having yellowish and transversally striated tubes, whose diameter also increases distally in T. hodgsoni. They also agree with T. longstaffi in the size of the nematocysts they share (cf. Table 4). Nevertheless, they appear to lack the larger stenoteles and, consequently, I prefer to keep them apart. I have found no differences between T. hodgsoni and the material described as T. ralphii by Hickson & Gravely (1907) and, therefore, this should be considered as T. hodgsoni. Ecology and distribution. Tubularia longstaffi was only known from McMurdo Bay, in the Ross Sea (Hickson & Gravely, 1907), where it was collected at a depth of 227 m, with gonophores in April. Present material, which constitutes the second record of the species, was collected at depths between 222 and 630 m, off Cape Adare, Adare Peninsula, Moubray Bay and Cape Hallet. Gonophores in February.

Tubularia hodgsoni Hickson & Gravely, 1907 (*) (Fig. 5; Table 4) Tubularia hodgsoni Hickson & Gravely, 1907: 13 –14, pl. 2 fig. 13, pl. 4 fig. 34; Dayton et al., 1970: 247. Tubularia ralphii — Hickson & Gravely, 1907: 13, pl. 2 fig. 12. Material examined. Tubularia hodgsoni Hickson & Gravely, 1907 (type material, Natural History Museum, London, Coel no. NHM 1907.8.20.7): McMurdo Bay, Ross Sea, Winter Quarters, January 1st, 1902, No. 6 hole, 240 m. Other material examined. Tubularia ralphii Bale, 1884 (sensu Hickson & Gravely 1907) (Natural History Museum, London, Coel no. NHM 1907.8.20.8): McMurdo Bay, Ross Sea, Winter Quarters, February 28th, 1902, 37 m. Description (Type of Tubularia hodgsoni). Hydrocaulus 40 mm high (Fig. 5 A) provided with hydrorhizal stolons (one of them branched). Stem diameter increasing distally, from ca. 0.5 mm basally to ca. 1 mm distally. Tube tortuous (Fig. 5 A), quite soft, particularly at distal part, yellowish, transversally striated throughout (Fig. 5 B). Polyp large, with marked constriction between head and neck (Fig. 5 C–D). Polyp with oral crown of ca. 60 filiform tentacles (Fig. 5 E), up to 2 mm long, in several rows, and aboral whorl of 24 filiform tentacles (Fig. 5 C–D), ca. 5 mm long. Polyp with 10 unbranched blastostyles, each with ca. 30 firmly adpressed gonophores (Fig. 5 D, F); lessdeveloped basally. Measurements (in µm). Cnidome: stenoteles [range 8.5–10.0 x 7.0–7.5, mean 9.3±0.5 x 7.2±0.2 (n=10); ratio, range 1.2–1.4, mean 1.3±0.1 (n=10)]; rounded haplonemes [range 14.0–15.5 x 10.0–13.0, mean 14.8±0.5 x 11.5±0.9 (n=10); ratio, range 1.2–1.4, mean 1.3±0.1 (n=10)]; tear-shaped haplonemes [range 13.5–15.0 x 4.5–6.0, mean 14.3±0.6 x 5.2±0.5 (n=10); ratio, range 2.5–3.1, mean 2.8±0.2 (n=10)]; desmonemes [range 6–6.5 x 4 –4.5]. Description (Tubularia ralphii sensu Hickson & Gravely 1907). Eight hydrocauli and fragments, up to 50 mm high, some quite tortuous. Tubes arising from branched hydrorhizal stolons. Tubes of approximately same diameter throughout, only slightly widening distally (e.g. 500 µm at base and 750 µm at distal end). Tubes yellowish and slightly transversally striated. Only one hydrocaulus with polyp, provided with oral crown of ca. 60 filiform tentacles and aboral whorl with 20 filiform tentacles. Unbranched blastostyles; gonophores firmly adpressed. Measurements (in µm). Cnidome: stenoteles [range 10.0 x 7.5–8.0, mean 10.0±0.0 x 7.8±0.2 (n=5); ratio, mean 1.3±0.0 (n=5)]; rounded haplonemes [range 14.5–15.5 x 10.5–11.5, mean 15.0±0.3 x 11.5±0.9 (n=7); ratio, range 1.3–1.5, mean 1.4±0.1 (n=7)]; tear-shaped haplonemes [range 13.0–14.0 x 5.0–5.5, mean 13.7±0.4 x 5.1±0.2 (n=5); ratio, range 2.6–2.8, mean 2.7±0.1 (n=5)]; desmonemes [range 6.0 x 4.5]. Remarks. See under discussion of Tubularia longstaffi Hickson & Gravely, 1907. Distribution. Only known from McMurdo Bay (Hickson & Gravely 1907; Dayton et al. 1970).

Tubularia hodgsoni Hickson & Gravely, 1907 (*) (Fig. 5; Table 4) Tubularia hodgsoni Hickson & Gravely, 1907: 13 ���14, pl. 2 fig. 13, pl. 4 fig. 34; Dayton et al., 1970: 247. Tubularia ralphii ��� Hickson & Gravely, 1907: 13, pl. 2 fig. 12. Material examined. Tubularia hodgsoni Hickson & Gravely, 1907 (type material, Natural History Museum, London, Coel no. NHM 1907.8.20.7): McMurdo Bay, Ross Sea, Winter Quarters, January 1st, 1902, No. 6 hole, 240 m. Other material examined. Tubularia ralphii Bale, 1884 (sensu Hickson & Gravely 1907) (Natural History Museum, London, Coel no. NHM 1907.8.20.8): McMurdo Bay, Ross Sea, Winter Quarters, February 28th, 1902, 37 m. Description (Type of Tubularia hodgsoni). Hydrocaulus 40 mm high (Fig. 5 A) provided with hydrorhizal stolons (one of them branched). Stem diameter increasing distally, from ca. 0.5 mm basally to ca. 1 mm distally. Tube tortuous (Fig. 5 A), quite soft, particularly at distal part, yellowish, transversally striated throughout (Fig. 5 B). Polyp large, with marked constriction between head and neck (Fig. 5 C���D). Polyp with oral crown of ca. 60 filiform tentacles (Fig. 5 E), up to 2 mm long, in several rows, and aboral whorl of 24 filiform tentacles (Fig. 5 C���D), ca. 5 mm long. Polyp with 10 unbranched blastostyles, each with ca. 30 firmly adpressed gonophores (Fig. 5 D, F); lessdeveloped basally. Measurements (in ��m). Cnidome: stenoteles [range 8.5���10.0 x 7.0���7.5, mean 9.3��0.5 x 7.2��0.2 (n=10); ratio, range 1.2���1.4, mean 1.3��0.1 (n=10)]; rounded haplonemes [range 14.0���15.5 x 10.0���13.0, mean 14.8��0.5 x 11.5��0.9 (n=10); ratio, range 1.2���1.4, mean 1.3��0.1 (n=10)]; tear-shaped haplonemes [range 13.5���15.0 x 4.5���6.0, mean 14.3��0.6 x 5.2��0.5 (n=10); ratio, range 2.5���3.1, mean 2.8��0.2 (n=10)]; desmonemes [range 6���6.5 x 4 ���4.5]. Description (Tubularia ralphii sensu Hickson & Gravely 1907). Eight hydrocauli and fragments, up to 50 mm high, some quite tortuous. Tubes arising from branched hydrorhizal stolons. Tubes of approximately same diameter throughout, only slightly widening distally (e.g. 500 ��m at base and 750 ��m at distal end). Tubes yellowish and slightly transversally striated. Only one hydrocaulus with polyp, provided with oral crown of ca. 60 filiform tentacles and aboral whorl with 20 filiform tentacles. Unbranched blastostyles; gonophores firmly adpressed. Measurements (in ��m). Cnidome: stenoteles [range 10.0 x 7.5���8.0, mean 10.0��0.0 x 7.8��0.2 (n=5); ratio, mean 1.3��0.0 (n=5)]; rounded haplonemes [range 14.5���15.5 x 10.5���11.5, mean 15.0��0.3 x 11.5��0.9 (n=7); ratio, range 1.3���1.5, mean 1.4��0.1 (n=7)]; tear-shaped haplonemes [range 13.0���14.0 x 5.0���5.5, mean 13.7��0.4 x 5.1��0.2 (n=5); ratio, range 2.6���2.8, mean 2.7��0.1 (n=5)]; desmonemes [range 6.0 x 4.5]. Remarks. See under discussion of Tubularia longstaffi Hickson & Gravely, 1907. Distribution. Only known from McMurdo Bay (Hickson & Gravely 1907; Dayton et al. 1970)., Published as part of ��LVARO L. PE��A CANTERO, 2017, Benthic hydroids (Cnidaria, Hydrozoa) from the Ross Sea (Antarctica) collected by the New Zealand Antarctic expedition BioRoss 2004 with RV Tangaroa, pp. 1-65 in Zootaxa 4293 (1) on pages 17-18, DOI: 10.11646/zootaxa.4293.1.1, http://zenodo.org/record/828475, {"references":["Hickson, S. J. & Gravely, F. H. (1907) Coelenterata. II. Hydroid zoophytes. National Antarctic Expedition (S. S. Discovery) 1901 - 1904, Natural History, 3, 1 - 34, pls. 1 - 4.","Dayton, P. K., Robilliard, G. A. & Paine, R. T. (1970) Benthic faunal zonation as a result of anchor ice at McMurdo Sound, Antarctica. In: Holdgate, W. (Ed.), Antarctic Ecology. Academic Press, London, pp. 244 - 257.","Bale, W. M. (1884) Catalogue of the Australian Hydroid Zoophytes. Australian Museum, Sydney, 198 pp., 19 pls."]}

Tubularia longstaffi Hickson & Gravely, 1907 (Figs 6���8; Table 4) Tubularia longstaffi Hickson & Gravely, 1907: 14 ���15, pl. 2 fig. 11. Material examined. Stn 71, 25 stems up to 55 mm high (NIWA 117482); Stn 72, six stems up to 60 mm high, without polyps (NIWA 117483); Stn 104, single stem 78 mm high, with gonophores (MNCN 2.03/531); Stn 105, 20 stems up to 110 mm high, most without polyps (MNCN 2.03/532); Stn 150, one stem 140 mm high (NIWA 117484); Stn 178, 19 stems up to 60 mm high, some without polyps, with gonophores (NIWA 117485); Stn 198, one stem 21 mm long, without polyp (NIWA 117486). Other material examined. Tubularia longstaffi Hickson & Gravely, 1907 (type material, Natural History Museum, London, Coel no. 1907.8.20.9): McMurdo Bay, Ross Sea, No. 6 hole, April 8th, 1903, 227 m. Description. Stem up to 140 mm high. Perisarc tube reaching base of polyp, yellow, transversally ringed (Fig. 6 A), relatively firm, becoming weak and translucent distally (Fig. 6 B). Tube diameter increasing distally, from ca. 250 ��m basally to 1 mm distally. Coenosarc attached to inner side of tube, with about 14 similar longitudinal lines. Polyps 2���5 mm high and 2���5 mm in maximum diameter, with aboral crown of 11 to 20 filiform tentacles (about 5 mm in length) (Fig. 6 C), and oral crown of 30���32 filiform tentacles (ca. 1.5 mm in length) (Fig. 6 D). Fertile polyps with ca. ten unbranched blastostyles (ca. 1150 ��m in length), each with ca. 17 gonophores (largest ca. 400 x 250 ��m) (Fig. 6 B���D). Cnidome (Fig. 7) consisting of stenoteles in two size classes, two types of haplonemes and desmonemes. Measurements (in ��m). Stn 178: Cnidome: stenoteles I [range 9.0���11.0 x 7.0���8.0, mean 10.0��0.7 x 7.7��0.4 (n=10); ratio, range 1.2���1.5, mean 1.3��0.1 (n=10)]; stenoteles II [range 11.5 x 11]; rounded haplonemes [range 13.0���15.0 x 9.0���11.0]; tear-shaped haplonemes [range 14.0���16.0 x 4.5���5.5, mean 14.4��0.6 x 5.1��0.3 (n=9); ratio, range 2.6���3.2, mean 2.9��0.2 (n=9)]; desmonemes [range 6.0 x 4.0]. Stn 150: Cnidome: stenoteles I, abundant [range 10.0���11.5 x 7.0���8.5, mean 10.4��0.5 x 7.6��0.5 (n=7); ratio, range 1.3���1.4, mean 1.4��0.1 (n=7)]; stenoteles II, scarce [range 13.5���14.0 x 12.0���13.0]; rounded haplonemes [range 14.0���16.0 x 9.5���11.0, mean 15.1��0.8 x 10.3��0.6 (n=6); ratio, range 1.4���1.6, mean 1.5��0.1 (n=6)]; tear-shaped haplonemes [range 13.5���17.0 x 4.5���6.0, mean 15.5��1.0 x 5.2��0.5 (n=7); ratio, range 2.3���3.4, mean 3.0��0.3 (n=7)]. Description (Type of Tubularia longstaffi). Stem broken into three parts: basal part corresponding to hydrorhizal stolon; 44 mm long middle part corresponding to basal part of stem (Fig. 8 A); distal part with hydranth (Fig. 8 C). Diameter of stem distinctly increasing distally, from ca. 0.5 mm basally to ca. 1.5 mm distally. Stem perisarc yellowish, transversally striated (Fig. 8 B). Stem with ca. 14 longitudinal coenosarc strands. Polyp (Fig. 8 C) with oral crown of over 50 filiform tentacles, aboral whorl with 25 filiform tentacles, ca. 13 mm long, merged basally. Blastostyles unbranched, with up to 23 well developed gonophores (Fig. 8 D���F), except by incipient grouped gonophores at base of blastostyles. Cnidome consisting of stenoteles, apparently in two size classes, two types of haplonemes and desmonemes. Measurements (in ��m). Cnidome: stenoteles I [range 10.0���10.5 x 7.0���8.0, mean 10.1��0.2 x 7.5��0.2 (n=10); ratio, range 1.3���1.4, mean 1.3��0.0 (n=10)]; stenoteles II [range 11.0���14.0 x 10.0���12.5, mean 12.7��1.2 x 11.5��1.1 (n=3); ratio, range 1.0���1.2, mean 1.1��0.1 (n=3)]; rounded haplonemes [range 15.0���16.0 x 10.5���12.0, mean 15.6��0.5 x 11.3��0.5 (n=10); ratio, range 1.3���1.5, mean 1.4��0.1 (n=10)]; tear-shaped haplonemes [range 14.5���16.0 x 5.0���6.5, mean 15.4��0.5 x 5.7��0.5 (n=10); ratio, range 2.5���3.0, mean 2.7��0.2 (n=10)]; desmonemes [range 6.5 x 4.5]. Remarks. After examining the type material of Tubularia longstaffi, I have no doubt that the BioRoss 2004 material belongs to that species, by their similar stem structure and cnidome. Diameter of the stem distinctly increases distally and the perisarc is yellowish and transversally striated. In relation to the cnidome, both have stenoteles, in two size classes, two types of haplonemes and desmonemes, all of similar size (cf. Table 4). The only difference is the slightly smaller number of oral tentacles in the present material (type material of T. longstaffi with over 50 tentacles). Tubularia Tubularia ralphii Tubularia Tubularia Tubularia hodgsoni (Hickson & longstaffi longstaffi longstaffi (Type) Gravely��� material) (Type) Stn 150 Stn 178 Smaller Range 8.5���10.0 x 10.0 x 10.0���10.5 x 10.0���11.5 x 7.0��� 9.0���11.0 x stenoteles 7.0���7.5 7.5���8.0 7.0���8.0 8.5 7.0���8.0 Mean 9.3��0.5 x 10.0��0.0 x 10.1��0.2 x 10.4��0.5 x 10.0��0.7 x 7.2��0.2 (n=10) 7.8��0.2 (n=5) 7.5��0.2 (n=10) 7.6��0.5 (n=7) 7.7��0.4 (n=10) Rounded Range 14.0���15.5 x 14.5���15.5 x 15.0���16.0 x 14.0���16.0 x 9.5��� 13.0���15.0 x haplonemes 10.0���13.0 10.5���11.5 10.5���12.0 11.0 9.0���11.0 Mean 14.8��0.5 x 15.0��0.3 x 15.6��0.5 x 15.1��0.8 x - 11.5��0.9 (n=10) 11.5��0.9 (n=7) 11.3��0.5 (n=10) 10.3��0.6 (n=6) Tear-shaped Range 13.5���15.0 x 13.0���14.0 x 14.5���16.0 x 13.5���17.0 x 4.5��� 14.0���16.0 x haplonemes 4.5���6.0 5.0���5.5 5.0���6.5 6.0 4.5���5.5 Mean 14.3��0.6 x 13.7��0.4 x 15.4��0.5 x 15.5��1.0 14.4��0.6 x 5.2��0.5 (n=10) 5.1��0.2 (n=5) 5.7��0.5 (n=10) x 5.2��0.5 (n=7) 5.1��0.3 (n=9) Larger Range - - 11.0���14.0 x 13.5���14.0 x 12.0��� 11.5 x 11 stenoteles 10.0���12.5 13.0 Mean - - 12.7��1.2 x - - 11.5��1.1 (n=3) Desmonemes 6.0���6.5 x 6.0 x 4.5 6.5 x 4.5 - 6.0 x 4.0 4.0���4.5 I have also studied the type material of Tubularia hodgsoni and the material assigned to Tubularia ralphii by Hickson & Gravely (1907). Both agree with T. longstaffi, and the material studied here, in the structure of the stem, having yellowish and transversally striated tubes, whose diameter also increases distally in T. hodgsoni. They also agree with T. longstaffi in the size of the nematocysts they share (cf. Table 4). Nevertheless, they appear to lack the larger stenoteles and, consequently, I prefer to keep them apart. I have found no differences between T. hodgsoni and the material described as T. ralphii by Hickson & Gravely (1907) and, therefore, this should be considered as T. hodgsoni. Ecology and distribution. Tubularia longstaffi was only known from McMurdo Bay, in the Ross Sea (Hickson & Gravely, 1907), where it was collected at a depth of 227 m, with gonophores in April. Present material, which constitutes the second record of the species, was collected at depths between 222 and 630 m, off Cape Adare, Adare Peninsula, Moubray Bay and Cape Hallet. Gonophores in February., Published as part of ��LVARO L. PE��A CANTERO, 2017, Benthic hydroids (Cnidaria, Hydrozoa) from the Ross Sea (Antarctica) collected by the New Zealand Antarctic expedition BioRoss 2004 with RV Tangaroa, pp. 1-65 in Zootaxa 4293 (1) on pages 19-21, DOI: 10.11646/zootaxa.4293.1.1, http://zenodo.org/record/828475, {"references":["Hickson, S. J. & Gravely, F. H. (1907) Coelenterata. II. Hydroid zoophytes. National Antarctic Expedition (S. S. Discovery) 1901 - 1904, Natural History, 3, 1 - 34, pls. 1 - 4."]}

Marine hydroids are commonly thought to be defended by stinging organelles called nematocysts that penetrate predator tissues and inject proteinaceous venoms, but not all hydroids possess these nematocysts. Although an increasing number of bioactive secondary metabolites have been isolated from marine hydroids, ecological roles of these compounds are poorly known. To test the hypothesis that nematocysts and noxious secondary metabolites represent alternative defenses against predation, we examined hydroids from North Carolina, United States for: (1) the palatability of whole polyps before and after nematocysts had been deactivated; (2) the palatability of their chemical extracts; and (3) their nutritional value in terms of organic content, protein content, and levels of refractory structural material (chitin). All hydroids were avoided by a generalist predator, the pinfish Lagodon rhomboides, compared with palatable control foods. Two of these (Halocordyle disticha and Tubularia crocea) became palatable after being treated with potassium chloride to discharge their nematocysts, suggesting that these species rely on nematocysts for defenses against predators. Chemical extracts from nematocyst-defended species had no effect on fish feeding. The four species that remained unpalatable after nematocysts had been discharged (Corydendrium parasiticum, Eudendrium carneum, Hydractinia symbiolongicarpus, Tridentata marginata) possessed chemical extracts that deterred feeding by pinfish. We have isolated and characterized the structures of the deterrent metabolites in two of these species. We found no differences in nutritional content or levels of chitin between nematocyst-defended and chemically defended species, and no evidence that either of these played a role in the rejection of hydroids as prey. Our results suggest that, among hydroids, chemical defenses may be at least as common as nematocyst-based defenses and that the two may represent largely alternative defensive strategies. The four hydroid species with deterrent extracts represent four families and both sub-orders of hydroids, suggesting that chemical defenses in this group may be widespread and have multiple origins.

Tubularia sp. Distribution in South America: polyp���Pacific Ocean, Ecuador, at 2.19��S 80.90��W in Santa Elena Bay (Fraser 1938a); Atlantic Ocean, Argentina, at 51.02��S 68.54��W (Vervoort 1972; Blanco 1994a). Habitat: polyp���from 14 to 82m depth (Fraser 1938a; Vervoort 1972; Blanco 1994a)., Published as part of M. P. Oliveira 1,16, S P. Miranda 2, *,, Es W. Mianzan 10,, Ro E. Migotto 11,, Ne B. Nascimento 2,11, Eli Nogueira J��nior 12,, Er Qui��ones 13,, Izio Scarabino 14,, T��n Schiariti 10,, Io N. Stampar 15,, Tronolone 2, , Qu��ria B. & Onio C. Marques 2,11, 2016, Census of Cnidaria (Medusozoa) and Ctenophora from South American marine waters, pp. 1-256 in Zootaxa 4194 (1) on page 37, DOI: 10.11646/zootaxa.4194.1.1

Tubularia indivisa Linnaeus, 1758 Synonyms in the area: Tubularia indivisa var. antarctica Hartlaub, 1905 p. 537���538 [polyp]. Distribution in South America: polyp���Atlantic Ocean, South Georgia Islands (Hartlaub 1905 p. 537���538; Blanco 1994a)., Published as part of M. P. Oliveira 1,16, S P. Miranda 2, *,, Es W. Mianzan 10,, Ro E. Migotto 11,, Ne B. Nascimento 2,11, Eli Nogueira J��nior 12,, Er Qui��ones 13,, Izio Scarabino 14,, T��n Schiariti 10,, Io N. Stampar 15,, Tronolone 2, , Qu��ria B. & Onio C. Marques 2,11, 2016, Census of Cnidaria (Medusozoa) and Ctenophora from South American marine waters, pp. 1-256 in Zootaxa 4194 (1) on page 37, DOI: 10.11646/zootaxa.4194.1.1

Tubularia sp. Distribution in South America: polyp—Pacific Ocean, Ecuador, at 2.19°S 80.90°W in Santa Elena Bay (Fraser 1938a); Atlantic Ocean, Argentina, at 51.02°S 68.54°W (Vervoort 1972; Blanco 1994a). Habitat: polyp—from 14 to 82m depth (Fraser 1938a; Vervoort 1972; Blanco 1994a).

In order to reveal the structure of the sparsely known deeper sublittoral hard bottom communities of glacial Kongsfjorden, the macroepibenthos from six depth zones (30–200 m) was analysed. A total of 180 still images derived from 6-h video recorded at the Kongsfjordneset remotely operated vehicle station were assessed quantitatively. Overall 27 mainly suspension-feeding species/taxa were observed. Of these, two-thirds have an arcto-boreal distribution, while the remainder are cosmopolitan. The overall mean epibenthos abundance was 33 ind. m−2 with maximum values at 150 m depth (97.9 ind. m−2). The majority of the taxa inhabited the entire depth range. Encrusting red algae, an unidentified sponge and the sea anemone Urticina eques, characterized the assemblage of the shallow zone. The sea anemones Hormathia spp. were important below 30 m, the Serpulid polychaete Protula tubularia was characteristic for the community below 50 m and the demosponge Haliclona sp. was a key taxon between 100 and 200 m depth. Cluster analysis and non-metrical multidimensional scaling based on abundance data showed differences between the assemblages along the bathymetric gradient, but only in the shallower depths in relation to the substratum surface incline. As surface and tidal current impacts attenuate with increasing depth, there is a gradual trend from robust key species towards more fragile ones (i.e. P. tubularia), in line with the ‘Physical control hypothesis’.

This is the first genetic analysis comparing cultured endobacteria discovered in the tentacles of cnidarian species (Tubularia indivisa, Tubularia larynx, Corymorpha nutans, Sagartia elegans) with those found in the cerata tips of selected nudibranch species (Berghia caerulescens, Coryphella lineata, Coryphella gracilis, Janolus cristatus, Polycera faeroensis, Polycera quadrilineata, Doto coronata, Dendronotus frondosus). Shared pathogenic activities were found among other microorganisms in the Pseudoalteromonas tetraodonis group (TTX), and the Vibrio splendidus group (haemolytic, septicaemic, necrotic activity). Specific autochthonous endobacteria of extremely low similarity to their next neighbours were detected in nudibranch cerata. These organisms are regarded as new and unknown endobacteria; among them were Pseudoalteromonas luteoviolacea (95%), Orientia tsutsugamushi (84%), Gracilimonas tropica (96%), Balneola alkaliphia (95%), Loktanella rosea (97%). SEM micrographs provide insight into endobacterial aggregates in cnidarian tentacles and nudibranch cerata. Since certain nudibranch predators prey on cnidarian species, it is assumed that cnidarian tentacle bacteria are directly transferred to nudibranch cerata. The pathogenic endobacteria may contribute to the chemical defence of both the nudibranch and cnidarian species investigated.

[Extract] In the finfish industry, clean cage nets are essential for the health of the stock (Braithwaite & McEvoy 2005). The accumulation of biofouling, the unwanted attachment of marine organisms on submerged surfaces, decreases the water flow through nets. Subsequently, the water quality within sea cages is reduced, which may affect fish health negatively (Cronin, Cheshire, Clarke & Melville 1999; de Nys & Guenther 2009). Over the last decade, the hydroid Ectopleura larynx (syn. Tubularia larynx) has become one of the most common fouling organisms in the Norwegian fish farming industry, causing increasing problems for farmers (Guenther, Carl & Sunde 2009). The rapid growth of E. larynx on aquaculture nets requires fish farmers to clean their nets regularly, often on a fortnightly basis during the peak of the biofouling season between July and November (Guenther et al. 2009). To reduce biofouling, the majority of Norwegian salmon farmers use copper-based coatings on nets, combined with regular underwater high-pressure washing (200–300 bar) with rotating discs (Olafsen 2006). Anecdotal observations suggest that hydroids grow back faster once the first washing has taken place (B. Jensen, salmon farm manager, pers. comm.).

Four valid species of the genus Gymnogonos are known at this point of investigations: G. crassicornis (northern Atlantic and the Arctic Seas); G. obvolutus (northern Atlantic and the Arctic Seas); G. ameriensis (circumantarctic distribution) and the new species G. pacificus (northern Pacific). Other species, such as Corymorpha antarctica (Pfeffer, 1889) and Tubularia cingulata (Vanhöffen, 1910) from the southern hemisphere are recognized as ‘species inquirendae’. New descriptions and taxonomic discussions of the known Gymnogonos species have been proposed. This genus has a typical bipolar distribution in the classical meaning of this term. This genus origin may rise from tropical Corymorphidae by neoteny in the period of glacial cooling.

The use of the Blaschka marine models in North American educational institutions from 1870-1890 is detailed. Historical records of purchase from the Henry Augustus Ward papers and Leopold Blaschka's business notebooks and correspondence were examined to show how the models were received by curators and educators in North America, the significance of the models in marine biology education for secondary school teachers, and the role that Ward's Natural History Establishment played in the distribution of the models. A historical perspective of the business relationship between Henry Ward and Leopold Blaschka is presented. The taxa of the models ordered in North America are documented, as is the use of models demonstrating ontogeny of the organism. Educational practices of the period are explicated and the uses of the models to support contemporary biological concepts of the organism are elucidated through examination of Model 191a, a male colony of the hydroid, Tubularia.

We investigated the cover, community structure and abiotic environment of nine shipwrecks lying at increasing distance from the Belgian coast. Results indicated that all shipwrecks were strongly dominated by cnidarians in terms of biomass and by amphipods in terms of abundances. Based on their epifaunal composition, three groups of shipwrecks could be determined. Metridium senile dominated a species poor community of the coastal sites. On the same sites, a Tubularia larynx community with a more species-rich assemblage was also developing. The T. larynx community had a lower biomass value (102 g AFDW m(-2)) and significantly lower species richness compared to the other sites. The coastal sites were characterized by periodic salinity decreases, large seasonal temperature fluctuation, high total suspended matter load and reduced current velocity. Channel water masses influence the offshore sites causing a more stable temperature and salinity environment, less turbid waters and high current speed. Tubularia indivisa dominated this community, with an average biomass of 229 g AFDW m(-2). Intermediate sites were also dominated by T. indivisa, but a higher biomass (424 g AFDW m(-2)) was observed. They showed intermediate results for the abiotic parameters and fast current velocities. Hypotheses for the observed variation in community structures are discussed in the light of the abiotic characterization of the shipwrecks. (C) 2007 Elsevier Ltd. All rights reserved.

In recent years, offshore wind energy in the shelf seas of the southern North Sea is experiencing a strong growth. Foundations are introduced in mainly sandy sediments, and the resulting artificial reef effect is considered one of the main impacts on the marine environment. We investigated the macrobenthic fouling community that developed on the concrete foundations of the first wind turbines built in Belgian marine waters. We observed a clear vertical zonation, with a distinction between a Telmatogeton japonicus dominated splash zone, a high intertidal zone characterised by Semibalanus balanoides, followed by a mussel belt in the low intertidal–shallow subtidal. In the deep subtidal, the species turnover was initially very high, but the community was soon dominated by few species (Jassa herdmani, Actiniaria spp. and Tubularia spp.), and only seasonal dynamics within this species assemblage were observed after 1–1½ years. Ten non-indigenous species (NIS) were found. In the intertidal, eight out of the seventeen typical intertidal species observed were NIS, while only two out of a species pool of 80 species were NIS in the deep subtidal. NIS were found to use the foundations to expand their range and strengthen their strategic position in the area.

The trophic ecology and seasonal changes in the diet of the intertidal hydrozoan Tubularia crocea were studied analysing the enteron contents of hydranths collected each season of the year. The relationship between feeding rate, prey availability, and re-suspension processes caused by tidal currents was also assessed. The most prevalent food items were diatoms and crustaceans. The most remarkable differences occurred during summer, when crustaceans were more abundant than diatoms. Conversely, diatoms were the most abundant prey during other seasons, and they were almost the only prey found during winter. There was no relationship between abundances of primary prey items in the water column and their occurrences in stomach contents. Instead, most prey items consisted of benthic organisms, primarily two species of diatoms (Grammatophora marina and Licmophora abreviatta) and fragments (usually appendages) of the amphipods Caprella sp. and Jassa falcata. Most food items were digested within 4–4·5 hours. The mean number of items captured per polyp per day was determined to be 115·2±19·2 in summer, 93·6±14·4 in autumn, 76·8±21·6 in winter and 199·2±31·2 in spring. Prey biomass (dry weight) polyp−1 d−1 was 5·1 μg in summer, 2·3 μg in autumn, 1·8 μg in winter, and 6·3 μg in spring. These values, in relation to hydranth biomass (55·3 μg; dry weight), were equivalent to a food intake polyp−1 d−1 of 9·3%, 4·2%, 3·2% and 11·5% of its own weight, respectively.

Phoxichilidium tubulariae exhibits an encysted protonymphon development. Its fast developmental mode reduced the typical number of pycnogonid molts and developmental time from months as described for other pycnogonid species to fewer than 21 days. This developmental strategy exploited the seasonal abundance of Tubularia larynx. The larvae hatched, infested the hydroid, and developed inside the gastrovascular cavity. The larvae developed for several molts and then emerged, destroying the hydranth. Annual population dynamics of P. tubulariae were seasonal; density of adult animals was highest in mid-to-late summer with reproduction being greatest in July and August. The abundance of pycnogonids peaked as the hydroid population declined.

Abundance and seasonality of Tanystylum orbiculare Wilson, 1878 populations (Pycnogonida; Ammotheidae) associated with Sarsia sarsii (Loven, 1836) and Tubularia crocea (Agassiz, 1862) (Hydrozoa; Anthomedusae) are analysed and the semi-parasitic life cycle of this species is described. In the analysed population, the first larval stages were found exclusively as parasites of S. sarsii. During the attachment to the hydranths, protonymphon larvae of T. orbiculare feed by sucking the hydranths of the cnidarian. Change of host is not obligatory; juveniles and adults were found both on S. sarsii as on T. crocea, and adults were also observed on other invertebrates. In the Mar del Plata intertidal, Tanystylum orbiculare was the most common pycnogonid species on colonies of T. crocea and S. sarsii. Anoplodactylus petiolatus was less abundant on both species and A. assimilis was found only on T. crocea. Endeis spinosa is absent on hydroids from the Mar del Plata intertidal zone but ectoparasitic larvae and adults were found on Obelia longissima colonies from Mar del Plata harbour together with adults of T. orbiculare and A. petiolatus. Endoparasitic larvae of A. petiolatus were found associated with colonies of Bougainvillidae., No disponible

The influence of Ca2+ and Mg2+ ions on both atrichous isorhiza (AI) discharge and settlement of actinular larvae of the hydroid Tubularia mesembryanthemum was investigated. Mg2+-supplemented artificial seawater (ASW) completely inhibited both events at a concentration of 206 mM, whereas lowered Mg2+ concentrations enhanced them. Ca2+ ions in the bathing solution highly regulated AI discharge and settlement, and Mg2+ ions may down-regulate these events. The effect of inorganic Ca2+-channel blockers, including Gd3+ and La3+, was also examined. Larval settlement was inhibited by Co2+, Ni2+, Cd2+, La3+, and Gd3+, with half inhibitory concentrations (IC50) of 5800, 260, 53, 45, and 7 {mu}M, respectively; AI discharge was also inhibited by these ions, with IC50 values of 6600, 500, 78, 41, and 5 {mu}M, respectively. These results suggest possible involvement of stretch-activated Ca2+ channels in the signal transmission of both AI discharge and larval settlement.

Hermissenda crassicornis is a eurytrophic carnivorous opisthobranch mollusc that possesses long-term planktotrophic larvae. No morphological criteria for determining larval competence in this slug are reliable; thus competence has been established by inducing metamorphosis with the hydroid Tubularia crocea . The competence period lasts approximately three weeks at 12–17°C, the best time for inducing metamorphosis being from days 31–50 within a given egg mass, and more precisely from day 41 to 50, as concluded from several egg masses. Within-clutch and between-clutch variability exists in both Tubularia -induced and spontaneous metamorphosis. Variability within egg masses in Hermissenda is probably due to the gradual acquisition of metamorphic competence. Spontaneous metamorphosis increases significantly as larvae age within a given egg mass. Metamorphosis is non-specific, since the larvae are able to metamorphose with several natural inducers, such as other hydroids ( Pennaria sp.) and anemones ( Metridium senile and Haliplanella luciae ). Combinations of Tubularia with glutamate at 10 −4 M or with Mg 2+ at 20 mM significantly increased the metamorphic yields, while NH 4 + was ineffective. K + at 30 mM and Cs + at 1 mM also increased the metamorphic yields, although Cs + at 30 mM was toxic. Several combinations of the natural inducers and some cations also produced high metamorphic yields, up to 25%. The effect of epinephrine at 10 −5 M in increasing the metamorphic yields, when used in combination with Tubularia , was equal to that obtained when using aged epinephrine, indicating that the oxidized products of epinephrine are probably responsible for this activity. Increasing the temperature from 12°C up to 17°C also had a significant effect in increasing the metamorphic yields with several inducers. The extracts of Tubularia with several organic solvents did not have an inducing effect. The natural inducer from Tubularia seems to be a water-soluble compound. Aqueous extracts of Tubularia at high concentrations (about eight-times the normal amounts) produced yields up to 50±8.3% metamorphosis, i.e., five-times the maximum yields ever reported for Hermissenda .

Juveniles of various species were observed on the perisarc of the dead hydroid Tubularia larynx in the Gulf of St Lawrence, Canada, some at densities up to twenty times more than on other substrata. This suggested active microhabitat selection by settling larvae. Here the results are reviewed of three field experiments using arborescent substrata, which tested whether recruitment of invertebrates could be accounted for by a passive model of encounter, or whether activity of larvae, or settled juveniles, needs to be invoked to explain the distributions. The distribution of inert particles on arborescent structures was examined in a laboratory flume. Both branch diameter and branching heterogeneity of the structures were considered as independent variables. A comparison of laboratory and field results suggested that passive settlement processes (hydrodynamic) were sufficient to explain the recruitment patterns at scales greater than 3 cm. At small scales (ca 1 mm), however, the hypothesis of active larval a...

This paper is an account of Serpulidae (Annelida, Polychaeta) collected from the Arctic and Northern Atlantic Oceans by Soviet expeditions. This material is part of the collection of the Department of Hydrobiology at Moscow State University and the Zoological Museum of the Russian Academy of Sciences in St. Petersburg. We redescribe eleven species: Chitinopoma serrula, Ditrupa arietina, Filograna implexa, Hyalopomatus claparedii, Hydroides norvegicus, Placostegus tridentatus, Pomatoceros triqueter, Protula globifera, P. tubularia, Protis arctica, and Serpula vermicularis. A new species from this collection, Metavermilia arctica, was described in a previous publication. Original illustrations and distribution maps accompany all descriptions. We provide two separate taxonomic keys to specimens and tubes. The previous records of arctic serpulids and the present state of the taxonomy of the family are discussed. Based on the operculum-bearing specimens of Protis arctica found, and on previous similar...

The discharge of atrichous isorhiza (AI) from the aboral tentacle tips (ATT) is an integral process during settlement of actinula larvae of the marine hydroid Tubularia mesembryanthemum, since discharged adhesive tubules from AI anchor actinula to settlement substrata. Under experimental conditions, AI discharge was triggered either by contact with bacterial film-coated micropipettes or by exposure to artificial seawater (ASW) containing high concentrations of K+ ions (K+-ASW). Triggering of AI discharge required both contact by ATT with the substrata and the presence of Ca2+ions in the bathing solution. Changes in intracellular Ca2+ion concentration ([Ca2+]i) were monitored by measuring fluorescence images obtained from ATT of intact actinulae loaded with fura-2. An initial low [Ca2+]i(R340/380=1.0) value was rapidly elevated by K+-ASW treatment (R340/380=1.9) and simultaneously accompanied by AI discharge. These results suggest that Ca2+ions present in the bathing solution flow into nematocytes during the AI discharge process. J. Exp. Zool. 278:299–307, 1997. © 1997 Wiley-Liss, Inc.

Based on previous studies showing that both passive (flow around filamentous and ramose organisms) and active (selection towards chitin in the perisarc of dead hydroids) processes may be involved in the settlement of scallop larvae on natural substrata, we examine here the possibility of using artificial filamentous material coated with a thin film of chitinous material to maximize spat collection of the giant scallop, Placopecten magellanicus , on artificial collectors. Chitinous material from different sources (hydroid perisarcs and prawn, crab, and lobster exoskeletons) was purified and transformed, and used to coat Netron ® netting. Two types of collectors were used in three different field experiments. The first type of collector consisted of 13 g of Netron ® netting (15 mm mesh size), coated with a thin film of chitinous material, placed in 10 mm mesh cubic Vexar cages (10 × 10 × 10 cm). This type of collector was used in the first two experiments, respectively designed to test (1) the effect of the type (source) of chitinous film as well as (2) the combined effects of the type of chitinous film, the number of layers of chitin on the netting, and the surface texture (roughness) of the chitinous film. A third experiment was carried out with collectors made of 150 g (wet weight) of perisarc of dead hydroids Tubularia larynx placed into 10 cm cubic Vexar cages. Perisarcs were processed using various physical and chemical treatments to examine the stability of the cue(s) responsible for the settlement of scallop larvae and other associated bivalve species. A total of 110 collectors was placed in the water near Tongue Shoal, Passamaquoddy Bay, New Brunswick, Canada on 8 September 1994 and retrieved on 30 October 1994. These spat collectors were successful in collecting large numbers of spat of the giant scallop (8179 individuals) and other bivalve species (65 739 individuals). There was a significant positive effect of type of chitinous films on the mean number of spat of each bivalve species collected including the giant scallop P. magellanicus . Over 66% more bivalve and 35% more giant scallop spat were collected in the Netron ® collectors coated with chitinous films compared with control collectors (Netron ® without any coating). On the contrary, in collectors other than controls, we observed no significant effect of the types of chitinous films (prawn, hydroids, crab, lobster) and no consistent pattern of variation in spat recruitment among collectors offering different numbers of layers of chitin and surface textures (roughness). Finally, spat of scallop and other bivalve species were recruited in higher numbers (N spat · g −1 ) on ‘Hydroid’ compared with ‘Netron ® ’ collectors. Among the ‘Hydroid’ collectors there was an occasional lower recruitment with bleached hydroids but no significant differences in the number of spat collected by the hydroids which were either not treated, deproteinized or boiled.

Observations were made on the diet and distribution of eight species of nudibranchs found in Borge Bay, Signy Island, Antarctica. Specimens from seven sites were examined in situ on four separate occasions during 1992 and 1993 using SCUBA. A small collection for identification was also made Six of the eight species present were identified, and the first ecological data for at least one species (Charcotia granulosa) were recorded. Notaeolidia gigas was feeding principally on hydroids of the genus Tubularia over the entire depth range surveyed (3–36 m), and was most abundant in shallow water, whereas Truomella belli was only found at deeper sites, mostly on an octocoral of the genus Ascolepis. Charcoaa granulosa and Pseudotritoma gracilidens appeared to be specialist bryozoan feeders and, as has been found at other locations, Austrodoris kerguelenesis specialised on the demosponge Dendnlla antarcnca. Two unidentified aeolid species occurred almost entirely on particular hydroids and the prey of Tritonia antarctica was not apparent. The physical size of Antarctic nudibranchs may have important implications to the type of prey and feeding strategy used by different species.

This exper~mental study examines the importance of active and passive processes during the settlement of the barnacle Balanus sp. and the hydrozoan Tubulana crocea larvae. Three hypotheses were tested: (1) larvae of Balanus sp. and 7 crocea exhibit settlement preferences with respect to scales of topographic heterogeneity (0, 1, 10 and 100 mm V-shaped grooves); (2) these preferences are modified by substratum complexity (combinations of scales of topographic heterogeneity); and (3) these preferences are mediated by larval behaviour directly on or near the substratum (benthic behaviour: after initial contact with the substratum). Artificial PVC panels of different scales of heterogeneity and complexity were submerged 30 cm below the surface during autumn 1992, a t Beaufort, North Carolina, USA. A companson between the final attachment sites of larvae with their initial contact sites on complex hard substrata was used to determinc the role of larval exploration following initial contact. Results indicated that, for Balanus sp. and T crocea larvae, all 3 hypotheses were confirmed. Evidence of actlve behaviour was observed at the spatial scales considered In t h ~ s tudy (entire panels and types of surfaces within panels), suggesting that active selection occurs at smaller and smaller scales. Balanus sp. larvae were rllure abundant on pancls which d ~ d not include the 1 mm scale of heterogeneity while, at the level of types of surfaces within each panel, they settled preferentially in grooves of 1 and 10 mm. T h ~ s uggests that different factors affect the competent 1a1-vae at d~fferent spatial scales. For T. crocea, the larvae selected the most complex type of panels and generally settled on the most exposed surfaces. Differences between initial larval contact sites and flnal attachment sltes confirmed the benthic behaviour hypothesis.

We predicted that both refuge dimension and growth form would influence settlement and short-term post-setUement success (57 d) of sessile marine invertebrates that live attached to hard substrata in low energy environments. Individuals with unlimited attachment to the substrata should rapidly be protected by their growth form, thus decreasing their need to settle in refuges and limiting the length of time any locations on heterogeneous substrata act as refuges. Alternatively, organisms with limited attachment to the substrata should remain susceptible to the causes of mortality for a longer time, and as a result should settle in high quality refuges [sites that protect individuals from competitors, predators or physical disturbance events until either a size refuge or reproductive maturity is obtained). Results agreed with these predictions for 4 species of invertebrates examined on both the topographically complex surface of the solitary ascidian Styela plicata (hereafter Styela) and on settlement plates w ~ t h uniformly spaced roughness elements that mimicked the heights of roughness elements (2.0 and 5.0 rnm) found on Styela in Beaufort, North Carollna, USA. On all surfaces, the 2 species with limited attachment to the substrata, Balanus sp. (aclonal, solitary) and Bugula neritina (clonal, arborescent), settled almost exclusively in the location that provided individuals with the best refuge: the crevices formed where the bases of roughness elements intersect with the flat surfaces. Additionally, when roughness elements of various heights were present (Styela, range: 0 6 to 8.8 mm), intermediate size roughness elements (2.0 < X 1 5 . 0 mm) were picked over 72% of the time. Settlement locations and locations where survival were enhanced were less consistent for the 2 species with unlimited attachment to the substrata: a clonal, encrusting form (Schjzoporella errata) and a clonal stolon-mat form (Tubularia crocea). Fewer individuals of these 2 species settled on roughness elements on Styela and when they did, they were not restricted to the bases of the roughness elements. On the plate surfaces, most settlement did occur in crevices, but both species grew away from this location w~thin days and short-term survival was not consistently greater in this location. Additional trials were run on plates with pits of the same maximum dimensions as the tested roughness elements (2.0 and 5.0 mm depth) to see if crevices and pits provide refuges of equal quality for newly settled individuals. Only survival of Balanus sp. recruits was greatest in both crevlces and pits. Evidence for active choice of settlement location comes from consistent results in trials in which some larvae settled in greater numbers on specific size roughness elements on Styela and in areas of high erosion. Overall, these results show that one must be very cautious when generalizing about refuge quality on heterogeneous surfaces, and to determine if a location is a spatial refuge, i t is critical to consider: (1) the dimensions of the larva, (2) the relative dimensions of the individual and potential refuge location at any point in time from the moment settlement occurred, and (3) the growth form of the individual which is related to its need for protection from biotic and abiotic sources of mortality.

A field experiment was carried out from 20 September to 9 November 1992 in the Baie des Chaleurs (Gulf of St. Lawrence) to examine the temporal pattern of Iceland scallop ( Chlamys islandica ) spat settlement on artificial filamentous collectors. One hundred sixty five cubic Vexar cages (10 × 10 × 10 cm) filled with 150 g (wet weight) of dead hydroids ( Tubularia larynx ) perisarcs were deployed and retrieved using a sequential time exposure schedule [collectors were deployed in decreasing numbers (30 to 5) every ≈ 5 days and retrieved in the reverse order (5 to 30) of their immersion]. This approach gave independent samples with respect to time and made it possible to estimate (1) near instantaneous settlement density, (2) short-term post-settlement mortality, (3) cumulative collection efficiency, and to compare (4) settlement onto substrata immersed for different periods of time. Simultaneous measurement of environmental factors (tidal range, current speed, seawater temperature and salinity) allowed an assessment of the relative influence of environmental factors in determining settlement density. The spat collectors used in this study were successful in collecting many thousands of Iceland scallop post-larvae. Settlement took place during 1 month, from the middle of September to the middle of October 1992 and collectors immersed for 10, 15, and 20 days collected significantly more spat than those immersed for 5 days. After the settlement season, spat mortality remained low for at least an additional 25 days (the end of the observation period). The daily mean density (DMD) of newly settled spat during each ≈ 5-day interval varied significantly in time and there was no significant correlation between DMD and the environmental factors. Different hypotheses concerning larval flux (no. of larvae × mean current speed) and their probability of coming into contact and being retained by a collector (retention efficiency) are proposed to explain the temporal pattern of spat collection observed in this study. Some suggestions are made to enhance collection efficiency of artificial scallop spat collectors.

Tubularia indivisa Linnaeus, 1758 Fig. 18 Tubularia indivisa Linnaeus, 1758: 803.— Segerstedt, 1889: 11, 24.— Lönnberg, 1902: 173; 1903: 59.— Jäderholm, 1909: 42, pl. 2, figs. 4–5.— Gislén, 1930: 350.— Rees & Rowe, 1969: 7.— Jägerskiöld, 1971: 64.— Jonsson et al., 2004: 166.— Schuchert, 2010: 343, fig. 2A. Type locality. “ Habitat in Oceano Europaeo ” (Linnaeus 1758: 803). Museum material. Kosterhavet, 58°53.093’N, 11°05.668’E, 20–30 m, 09.ix.2010, biological dredge, R / V Nereus, two stems with hydranths, up to 9.5 cm high, one with incipient gonophores, ROMIZ B3908. Remarks. Details on taxonomy, nomenclature, distribution, and general biology of Tubularia indivisa Linnaeus, 1758 are provided in a recent monograph by Schuchert (2010). He noted that the identity of Tubularia divisa Osburn, 1893 is unclear, but that the name is perhaps a spelling mistake. In briefly describing the species, Osburn (1893) associated it with accounts in Seaside Studies (E.C. Agassiz & A. Agassiz 1865) of Tubularia couthouyi L. Agassiz, 1862 and in The Riverside Natural History (Clarke 1888) of Parypha crocea L. Agassiz, 1862 (= Ectopleura crocea), together with a plate of Tubularia indivisa. The name is taken here to be an incorrect subsequent spelling of T. indivisa and, as such, not an available name (ICZN Art. 33.3). The status of T. couthouyi remains unresolved, with Fraser (1944) maintaining it as valid, Petersen (1990) regarding it conspecific with T. indivisa, and Schuchert (2010) considering it questionably so. Tubularia indivisa is relatively common in southwestern Scandinavia, particularly at depths of about 10–100 m (Kramp 1935b; Rees & Rowe 1969; Jägerskiöld 1971; Christiansen 1972). Christiansen found fertile colonies from February to May in the Oslofjord. Reported distribution. West coast of Sweden.—From the border with Norway (Jägerskiöld 1971) to the Öresund (Segerstedt 1889). Elsewhere.—North Atlantic from northern seas of the Russian Federation to Ghana (Schuchert 2010) in the east, and from west Greenland (Schuchert 2001a) and the Gulf of St. Lawrence to Block Island Sound (Fraser 1944) in the west. This species has also been reported in the boreal North Pacific Ocean from the Bering Sea to northern Japan in the west, and from Alaska to Washington state in the east (Petersen 1990)., Published as part of Calder, Dale R., 2012, On a collection of hydroids (Cnidaria, Hydrozoa, Hydroidolina) from the west coast of Sweden, with a checklist of species from the region 3171, pp. 1-77 in Zootaxa 3171 (1) on page 19, DOI: 10.11646/zootaxa.3171.1.1, http://zenodo.org/record/5247704, {"references":["Linnaeus, C. (1758) Systema naturae per regna tria naturae, secundum classes, ordines, genera, species cum characteribus, differentiis, synonymis, locis. Editio decima, reformata. Laurentii Salvii, Holmiae, 823 pp.","Segerstedt, M. (1889) Bidrag till kannedomen om hydroid-faunan vid Sveriges vestkust. Bihang till Kongliga Svenska Vetenskaps-Akademiens Handlingar, 14, Afdelning 4, 4, 1 - 28.","Lonnberg, E. (1902) Nagra smarre iakttagelser rorande faunan i Bohuslan i mars manad 1902. Ofversigt af Kongliga Vetenskaps-Akademiens Forhandlingar, 59, 169 - 174.","Lonnberg, E. (1903) Undersokningar rorande Skeldervikens och Angransande Kattegat-omrades djurlif pa Forordnande af Kongl. Landtbruksstyrelsen. Meddelanden fran Kongl. Landtbruksstyrelsen, ar 1902, 80, 1 - 70.","Jaderholm, E. (1909) Northern and Arctic invertebrates in the collection of the Swedish State Museum (Riksmuseum). IV. Hydroiden. Kungliga Svenska Vetenskapsakademiens Handlingar, ny foljd, 45 (1), 1 - 124.","Gislen, T. (1930) Epibioses of the Gullmar Fjord II. Kristinebergs Zoologiska Station 1877 - 1927, Skriftserie Utgiven av K. Svenska Vetenskapsakademien, 4, 1 - 380.","Rees, W. J. & Rowe, M. (1969) Hydroids of the Swedish west coast. Acta Regiae Societatis Scientiarum et Litterarum Gothobergensis, Zoologica, 3: 1 - 23.","Jagerskiold, L. A. (1971) A survey of the marine benthonic macro-fauna along the Swedish west coast 1921 - 1938. Acta Regiae Societatis Scientiarum et Litterarum Gothobergensis, Zoologica, 6, 1 - 146.","Jonsson, L. G., Nilsson, P. G., Floruta, F. & Lundalv, T. (2004) Distributional patterns of macro- and megafauna associated with a reef of the cold-water coral Lophelia pertusa on the Swedish west coast. Marine Ecology Progress Series, 284, 163 - 171.","Schuchert, P. (2010) The European athecate hydroids and their medusae (Hydrozoa, Cnidaria): Capitata Part 2. Revue Suisse de Zoologie, 117, 337 - 555.","Osburn, H. L. (1893) Biological descriptions of certain common hydroid animals. American Monthly Microscopical Journal, 14, 94 - 100.","Agassiz, E. C. & Agassiz, A. (1865) Seaside studies in natural history. Marine animals of Massachusetts Bay. Radiates. Ticknor & Fields, Boston, 155 pp.","Agassiz, L. (1862) Contributions to the natural history of the United States of America. Vol. IV. Little, Brown & Company, Boston, 380 pp.","Clarke, S. F. (1888) Branch III. - Coelenterata. Class I. - Hydrozoa. Order I. - Hydroidea. In: Kingsley, J. S. (Ed.), The Riverside Natural History. Volume I. Lower invertebrates. Kegan Paul, Trench & Co., London, pp. 73 - 89.","Fraser, C. M. (1944) Hydroids of the Atlantic coast of North America. University of Toronto Press, Toronto, 451 pp.","Petersen, K. W. (1990) Evolution and taxonomy in capitate hydroids and medusae (Cnidaria: Hydrozoa). Zoological Journal of the Linnean Society, 100, 101 - 231.","Kramp, P. L. (1935 b) Polypdyr (Coelenterata) I. Ferskvandspolypper og goplepolypper. Danmarks Fauna, 41, 1 - 207.","Christiansen, B. O. (1972) The hydroid fauna of the Oslo Fiord in Norway. Norwegian Journal of Zoology, 20, 279 - 310.","Schuchert, P. (2001 a) Hydroids of Greenland and Iceland (Cnidaria, Hydrozoa). Meddelelser om Gronland, Bioscience, 53, 1 - 184."]}

We examined the development of the fouling community on pearl nets and its effect on the growth of juvenile Placopecten magellanicus at Grande-Riviere and Gascons in the Baie des Chaleurs. The total biomass of fouling organisms was 2–3 times greater at Gascons than at Grande-Riviere and at both sites decreased with increasing depth. Throughout the study, at Grande-Riviere, at the mouth of the bay, the fouling community was dominated by two bivalves, Mytilus edulis and Hiatella arctica, and the hydroid Obelia gelatinosa was third in abundance. In contrast, at Gascons, 40 km inside the bay, the hydroid Tubularia larynx predominated in the summer while M. edulis and H. arctica predominated in the autumn. Factors potentially explaining the success of M. edulis and H. arctica in the fouling community are the loss of hydroids due to selective grazing by nudibranchs, the rapid growth rate of the bivalves and their ability to inhibit settlement of competitors. Changing the pearl nets regularly results in a sharp increase in the yield of muscle and other soft tissues, but only a slight increase in shell height of the cultured scallops. For example, for a 30-mm scallop suspended at 9 m in depth for 4 months, the increase in muscle mass is 68% greater in cleaned than in fouled nets whereas the difference is only 4.8% for shell height. Because fouling decreases with depth and also varies markedly between localities, judicious choosing of culture sites in term of fouling development could substantially improve meat production.

Settlement responses to boundary-layer flow of several invertebrate taxa, including the hydroid Tubularia crocea, the bryozoans Bugula turrita and Schizoporella unicornis, and the tube-building polychaete Hydroides dianthus were studied in manipulated field flows in Great Harbor, Massachusetts, USA. During three experiments in 1989 and two in 1990, densities of newly-recruited larvae were measured on flat plates, whose flow regimes had been manipulated by altering the leading-edge configurations. Settlement responses to flow were strongly species-specific, with T. crocea preferring regions of both high turbulence and strong shear stress, and S. unicornis settling a most exclusively in regions of high shear stress. B. turrita settled most prominently in regions of reduced shear stress, exhibiting settlement patterns that closely approximated predictions from a model of passive particle contact. H. dianthus showed a moderate avoidance of regions with high shear stress. These results indicate that boundary-layer flows affect settlement of several common encrusting species, a probable consequence of larval behaviors such as substrate rejection or exploration in response to flow. These responses are likely to generate patchiness during initial colonization of natural habitats, and certainly affect colonization of settlement panels commonly used in marine ecological studies.

Each cnidocil complex of the hydrozoans Tubularia larynx and Hydra vulgaris consists of 9 or 7–10 large stereovilli (=stereocilia), respectively, and a modified cilium, the cnidocil. The cnidocils comprise the regular 9 microtubule doublets, up to 30 additional microtubules, as well as a central filament body. Adjacent stereovilli are linked together by intermembrane connectors forming the stereovillar cone. The distal tips of the stereovilli surround the cnidocil in a closed tubular arrangement measuring up to 0.7 μm in length. Within this contact region the cnidocil is linked to the stereovillar tube by another set of intermembrane connectors, which seem to hold the cnidocil in a central position within the stereovillar cone. Stereovillar membrane and actin core are linked by 16-nm long cross bridges, which display a periodicity of 16 nm and emerge from the actin core. Within the cnidocils periodically arranged membrane-cytoskeleton bridges are uniformly restricted to the contact region. Here, 24-nm long cross bridges, which are spaced by a regular distance of 20 nm, interconnect the A-tubules of the microtubule doublets and the membrane. The cnidociliary membrane is differentiated into distinct domains as revealed by freeze-fracturing. Within the contact region of the nematocytes of Tubularia larynx, intramembrane particles are arranged in 9 rows of 700 nm length and 50 nm width, separated by particlefree areas. Intramembrane particles are irregularly distributed distal to the contact region. Considering recent physiological results we presume that the latter represent chemoreceptor units, while mechanical stimuli are transmitted via the intermembrane connectors and the microtubule-membrane bridges to mechanosensitive channels within the domain of the cnidociliary membrane in the contact region.

We investigated the cover, community structure and abiotic environment of nine shipwrecks lying at increasing distance from the Belgian coast. Results indicated that all shipwrecks were strongly dominated by cnidarians in terms of biomass and by amphipods in terms of abundances. Based on their epifaunal composition, three groups of shipwrecks could be determined. Metridium senile dominated a species poor community of the coastal sites. On the same sites, a Tubularia larynx community with a more species-rich assemblage was also developing. The T. larynx community had a lower biomass value (102 g AFDW m-2) and significantly lower species richness compared to the other sites. The coastal sites were characterized by periodic salinity decreases, large seasonal temperature fluctuation, high total suspended matter load and reduced current velocity. Channel water masses influence the offshore sites causing a more stable temperature and salinity environment, less turbid waters and high current speed. Tubularia indivisa dominated this community, with an average biomass of 229 g AFDW m-2. Intermediate sites were also dominated by T. indivisa, but a higher biomass (424 g AFDW m-2) was observed. They showed intermediate results for the abiotic parameters and fast current velocities. Hypotheses for the observed variation in community structures are discussed in the light of the abiotic characterization of the shipwrecks.

The Fabriciinae genus Fabricia Blainville is revised. In the past, the type species designation for the genus has been confused; explicit designations have included Tubularia fabricia Muller and Amphicora sabella Ehrenberg. The type species is actually T. stellaris {SCMuller}, by monotypy. Based on this latter designation, most species previously placed into synonymy with F. sabella are now junior synonyms of F. stellaris, including F. sabella. A neotype is designated and described for F. stellaris stellaris from the type locality. Examination of the type material of F. leidyi Verrill and Haplobranchus atlanticus Treadwell confirms these species are junior synonyms of F. stellaris. Geographic variability in pigmentation patterns and general body proportions in F. stellaris are discussed. Fabricia contains three subspecies: F. stellaris stellaris; F. stellaris adriatica (Banse), new combination; F. stellaris caspica (Zenkevitsch), new combination. The following species, based on inadequate descrip...

Aeolid nudibranchs maintain nematocysts sequestered from their cnidarian prey for protection against predators. Selection for nematocyst incorporation is a function of diet and prey choice, but ratios vary among nudibranchs feeding on a given diet, indicating that other factors may be involved. It is proposed that the presence of predators influences nematocyst incorporation. Nematocyst uptake in the nudibranch Flabellina verrucosa collected from the southern Gulf of Maine was examined in response to various potential predators, including Crossaster papposus, Tautogolabrus adspersus, and Carcinus maenas. Nudibranchs in individual flow-through containers feeding on a diet of the hydroids Tubularia spp. and Obelia geniculata were subjected to tanks containing a predator, then their nematocyst distribution was examined. Although most of the changes over the experimental period were attributable to diet, F. verrucosa responded to both T. adspersus and C. papposus by significantly increasing microbasic mastigophore incorporation. No differential uptake was seen with C. maenas. Response was evident in the nudibranchs both for predators present in the collection area and for those with which they had no previous exposure, indicating that F. verrucosa modulates nematocyst incorporation in response to the presence of predators as well as to diet. A coevolution of nudibranchs and potential predators may govern changes in nematocyst uptake.

The marine colonial hydroid Tubularia mesembryanthemum produces a morphologically unique dispersive stage, the actinula larva. Detailed observations were made on the behaviors and nematocyte dynamics of actinula larvae during attachment and morphogenesis by employing microscopic and time lapse video techniques. These observations produced four primary results. (1) Actinula larvae demonstrated two forms of attachment: temporary attachment by atrichous isorhiza (AI)-nematocysts discharged from the aboral tentacle (AT) tips-and permanent settlement by cement secretion from the columnar gland cells of the basal protrusion. (2) During larval settlement, numerous AIs were discharged from the AT tips with sinuous movement and rubbing of the tentacles onto the substrata, leading to "nematocyte-printing" around the settlement site. (3) Simultaneous with the discharge of the AIs, migration of stenoteles, desmonemes, and microbasic mastigophores occurred, resulting in a dramatic change of nematocyte composition in the ATs after larval settlement. This was in parallel with changes in larval behavior and the tentacle function. (4) Nematocyte-printing behavior during settlement could be recognized as metamorphic behavior responsible for irreversible changes in AT function, from attachment to feeding and defense.

8 pages, 6 figures, 1 table, The diet of four species of Antarctic cnidarians, two hydroids and two anthozoans, was investigated. One hydroid, Tubularia ralphii, and one anthozoan, Anthomastus bathyproctus, seem to basically consume zooplankton whereas the other hydroid species, Oswaldella antarctica, has a diet mainly based on the fine fraction of seston. The last cnidarian investigated, the stoloniferan alcyonacean, Clavularia cf. frankliniana, feeds mainly on resuspended material. The wide range of diets of these Antarctic cnidarians indicates opportunistic behaviour by feeding on different sources and taking advantage of the available food sources. Data related to low C/N ratios in the sediment and high NO2 concentrations in areas with dense communities of benthic suspension feeders, along with data on capture rates, lead us to hypothesize that these organisms play an important role in the recycling processes of organic matter in Antarctic benthic ecosystems

The feeding behavior and growth of the nudibranch mollusc Hermissenda crassicomis, a gener‐alist carnivore, has been studied; this species is widely used as a biomedical and neurobiological model. Relative to the stalks, polyps of the hydroid prey, Tubularia crocea, were preferentially consumed by adults of H. crassicomis at a fast rate. Starved slugs did not distinguish between reproductive and unreproductive polyps, but unstarved slugs did select unreproductive polyps of T. ‘crocea. Experiments with diets based on different parts of T. crocea (polyps, stalks, or whole) showed no obvious differences in juvenile growth among treatments, but survival of juveniles was low. Juveniles of H. crassicomis .grew better on a diet of the small anemone Haliplanella luciae than on T. crocea or the anemone Metridium senile. The relationship between body length and wet weight of H. crassicomis was similar for animals grown in the laboratory on a T. crocea diet and specimens from the field.

Este artículo contiene 8 páginas, 3 tablas., The nudibranch mollusc Hermissenda crassicornis can be cultured easily in the laboratory and has been used as a biomedical model for learning and memory studies. Cultured animals whose only prey was Tubularia crocea were tested for responses to other prey. Naive slugs were conditioned with six different diets and tested for behaviour in a Y-maze. H. crassicornis was able to detect chemotactically food items which it had never been in contact with (such as Pennaria), but it did not detect some of the conditioning diets (e.g. Metridium). At least three hydroid species induce a chemotactic behaviour in the slug. It is shown that ingestive conditioning does affect their response in single-choice and double-choice experiments. As food items other than cnidarians are also detected, it is likely that different Wairomones are responsible for the nudibranch's behaviour.

A taxonomic revision of Monotagma (Marantaceae) concludes that this genus comprises 37 species, of which the following 18 species are here described as new: M. aurantispathum, M. breviscapum, M. congestum, M. exile, M. flavicomum, M. floribundum, M. grallatum, M. humile, M. lilacinum, M. nutans, M. papillosum, M. paradoxum, M. remotum, M. roseum, M. septentrionale, M. spathulatum, M. tuberosum, and M. uliginosum. Furthermore, the new subspecies M. grallatum subsp. subcentricifolium is described. It is also proposed that these species are best treated in two monophyletic sections, viz. Monotagma sect. Monotagma with 20 species and the new Monotagma sect. Tubularia with 17 species. All new taxa are illustrated and described with notes on distribution and relationships, and a key to all recognized Monotagma species is given.