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The walls of the Chilean fjords are hotspots of biodiversity, but also threatened by the development of salmonid farming and coastal infrastructure. One of the consequences of these activities is the increase of sediment load in a region of high natural run-off. The cold-water coral (CWC) Caryophyllia huinayensis abounds on the steep slopes of the fjords. Its distribution, often in the shelter of overhangs, suggests a natural sensitivity to sedimentation, but actual data on the susceptibility of this coral species to sediment is lacking. Here, we explore sedimentation effects on the putatively sensitive juvenile stages of C. huinayensis. In general, it is important to understand the capabilities of CWC recruits to cope with anthropogenic impacts as their viability is the guarantee for the population future. In order to determine the resilience of juvenile C. huinayensis to sediment stress, a three-month aquaria experiment was conducted with three sediment loads: the current natural sediment concentration in Comau Fjord, 100- and 1000-fold higher values expected from local construction and coastal erosion. Measured response variables were polyp activity, and variation in coral mass and in calyx dimensions. Under high turbidity, polyp activity was clearly reduced, therefore significantly affecting prey capture effectivity and thus nutrition. Hence, the management plans for the area need to take into account the deleterious effects of increased sedimentation on vulnerable CWCs.

Present study aimed to characterize gastrointestinal parasites and culturable bacteria from free-living South American sea lions (Otaria flavescens) inhabiting waters of Comau Fjord, Patagonia, Chile. Therefore, a total of 28 individual fecal samples were collected from sea lions within their natural marine habitat during several diving expeditions. Using classical parasitological techniques, study revealed infections with five different gastrointestinal parasite genera. In addition, bacterial cultures showed presence of at least 28 different bacterial genera. Referring to parasites, protozoan, and metazoan species were found with some of them bearing anthropozoonotic potential and/or pathogenic impact for these marine mammals. As such, four of identified parasite genera harbored zoonotic potential (i.e., Entamoeba, Balantidium, Diphyllobothrium, Anisakis) and one genus (Parafilaroides) represented a specific lungworm of marine pinnipeds. Proglottids from fecal samples showed high morphological homology to “Diphyllobothrium” scoticum (Rennie and Reid, 1912; Meggitt, 1924), which was found in Antarctic sea leopards (Hydrurga leptonyx; Phocidae), but contained eggs of smaller size. Molecular characterization revealed 97–100% identity to a new “Diphyllobothrium” species which was recently isolated from a Californian sea lion (Zalophus californianus; Otariidae) in San Francisco. As such, O. flavescens represents a new host record for this parasite species. Furthermore, potential zoonotic bacteria (i.e., Clostridium, Escherichia, Vibrio, Yersinia, Salmonella) were identified amongst others in O. flavescens indicating a reservoir role for these pinnipeds in marine ecosystem. Current data should be considered as a baseline study for future monitoring surveys on anthropozoonotic pathogens circulating in wild free-living sea lions and their possible impact on public health issues and marine wildlife.

Cold-water corals (CWC) build complex, three-dimensional habitats for diverse communities of associated species. In spite of their importance, very little is known on their reproductive biology. In the Patagonian fjords of Chile, three caryophylliid CWC abound: Desmophyllum dianthus Es-per 1794 along with the recently described Caryophyllia huinayensis Cairns et al. 2005 and Tethocyathus endesa Cairns et al. 2005. This study reports first in situ and in vitro observations of the early life history of the latter two species along with in vitro growth data of juvenile C. huina-yensis. Both are brooding species with translucent tissues, which allowed us to detect and monitor larval development in the gastrovascular system of living specimens. In situ observations from summer 2017 showed between 15 and 25 milky white reproductive stages in the tentacle portion of the gastrovascular cavity of one adult specimen. Up to five younger, round stages were ob-served in groups in the tips of the tentacles. Small planulae of 1.13-1.28 mm length were observed in the tips of the tentacles or organized radially around the mouth. Observations from C. huina-yensis maintained (> 1 yr) in an aquarium system showed that the 620 µm large orange planulae may swim with a velocity of 230 µm s-1 and thus may move from the tentacle tip to the mouth within less than a minute and thereafter reappear in the same or another tentacle in the similar time. After release larvae were found to be negatively buoyant, crawl along the substrate and settle between four and 16 days. Recently settled juveniles increased their basal disc diameter with a rate of 10 µm d-1. After 30 months of maintenance in the aquarium system (Temperature: 12.5 °C, Salinity 32, pH 8, argonite >1, feed with Artemia salina nauplii twice a week) recruits may gain 4.22 (+/-) 0.03 mm yr-1 in diameter and reach the mean size observed for adults in the field after three years. Research on the early life history of CWC is important to understand larval dispersal and connectivity of populations threatened by a changing climate and increasing eutrophication by expanding salmon farming operations.

Cold-water corals play an important role as ecosystem engineers by providing the three-dimensional structural basis and habitat for a rich associated fauna. In southern Chile, the cold-water scleractinian Desmophyllum dianthus populates the steep walls of Comau Fjord. Where its principal energy source, the zooplankton, is less abundant in winter. This coral specie is often associated with filter-feeders, but the nature and possible trophic significance of this relationship remains enigmatic. Dense belts of the mussel Aulacomya atra and the brachiopod Magellania venosa thrive in the productive waters above and between D. dianthus, and both, visual observation and diver-operated push net samples revealed a rain of biodeposits (faeces and pseudofaeces) from these filter-feeders to the corals. This study aims to determine if the conversion by filter-feeders of microscopic plankton inaccessible to corals to macroscopic strings of faeces and pseudofaeces accessible to the corals’ tentacles may represent a new and so far overlooked trophic link channeling surface production to the corals. Preliminary in vitro experiments show that D. dianthus ingests biodeposits of the mussel Mytilus edulis, but only after the consumption of juvenile krill (Euphausia pacifica). This indicates that biodeposits of active filter feeders may play a role as a food supplement for corals. Follow-up experiments with biodeposits produced under natural conditions by the native filter-feeder community are expected to compound the evidence.

Sertularella hermanosensis El Beshbeeshy, 2011 Figs 11 B-G, 12A; Table 12 Sertularella hermanosensis El Beshbeeshy, 2011: 133, fig. 42. Sertularella geodiae. – p.p. Vervoort, 1972: 120, fig. 37. [non Sertularella geodiae Totton, 1930] Material examined: ZMH C11885; FRV Walther Herwig, Argentine Shelf, no additional data; four sterile colony fragments 7.0-1.4 cm high, each bearing several hydrothecae, with only the perisarc left. – NHML 1888.11.13.42; between Cabo Virgenes, Argentina, and the Falkland Is., Challenger Stn. 314, ca. 128 m; 3 infertile colony fragments (6, 12 and 18 mm high) among the holotype of Sertularella implexa (Allman, 1888) (for more details, see under this species), and a microslide (Fig. 12A). Description: Colonies composed of erect, monosiphonic, unbranched or sparingly-branched stems arising from stolonal fibers firmly adhering to substrate. Both stems and side branches divided into moderately long (though varied in length), imperceptibly geniculate to collinear internodes, by means of faint, oblique constrictions of the perisarc slanting in alternate directions. A hydrotheca to the distal end of each internode. Side branches generally arising from below the bases of every 3 stem hydrothecae by means of short, lateral apophyses. Hydrothecae biseriate, alternate, coplanar; flask-shaped, adnate for slightly more than half their length to the corresponding internode, slightly tumid adaxially; abaxial wall straight to slightly concave proximally, suddenly becoming convex below aperture; free adaxial wall wavy to distinctly transversely-ridged, ridges occasionally reaching abaxial wall; aperture with 4 short, equal, triangular cusps, separated by shallow embayments; renovations occasional; a 4-flapped operculum. Gonothecae unknown. Dimensions: See Table 12. Remarks: According to El Beshbeeshy (2011), his species has hydrothecae with different forms, and this is also evident from his fig. 42. As not all his material was reinspected for the purpose of the present study, it is assumed that those differences could indicate the presence of a mix of species. Distribution: Chile – Región de Magallanes y de la Antártica Chilena [Magellan Strait (Vervoort, 1972, as S. geodiae)]. Argentina – scattered records from the Patagonian Shelf, between ca. 41° S and Península Mitre (El Beshbeeshy, 2011). Elsewhere – between Cabo Virgenes, Argentina, and the Falkland Is. [present study (material co-occurring with the type of S. implexa); El Beshbeeshy, 2011]; off the NE coast of Falkland Is. (El Beshbeeshy, 2011); a large perimeter including the Strait of Magellan, the Falkland Is., the Burdwood Bank, Isla de los Estados, and Cape Horn (Vervoort, 1972, as S. geodiae)., Published as part of Horia R. Galea, Dirk Schories, Verena Häussermann & Günter Försterra, 2017, Taxonomic revision of the genus Sertularella (Cnidaria: Hydrozoa) from southern South America and the subantarctic, with descriptions of five new species, pp. 255-321 in Revue suisse de Zoologie 124 (2) on page 282, DOI: 10.5281/zenodo.893519, {"references":["El Beshbeeshy M. 2011. Thecate hydroids from the Patagonian shelf (Coelenterata, Hydrozoa, Thecata). Edited by G. Jarms. Verhandlungen des Naturwissenschaftlichen Vereins in Hamburg 46: 19 - 233.","Vervoort W. 1972. Hydroids from the Theta, Vema and Yelcho cruises of the Lamont-Doherty geological observatory. Zoologische Verhandelingen, Leiden 120: 1 - 247.","Totton A. K. 1930. Coelenterata. Part V. Hydroida. Natural History Report of the British Antarctic (\" Terra Nova \") Expedition, 1910. Zoology 5 (5): 131 - 252.","Allman G. J. 1888. Report on the Hydroida dredged by H. M. S. Challenger during the years 1873 - 76. Part II. - The Tubularinae, Corymorphinae, Campanularinae, Sertularinae and Thalamophora. Report on the Scientific Results of the Voyage of H. M. S. Challenger during the years 1873 - 76, Zoology 23 (70): 1 - 90."]}

Sertularella curta Galea & Schories, 2014 Fig. 7M, N Sertularella curta Galea & Schories, 2014 in Galea et al., 2014: 34, figs 6D-E, 7C. Sertularella geniculata. – Leloup, 1974: 28, fig. 23 [non Sertularella geniculata Hincks, 1874 = Sertularella tenella (Alder, 1857)]. Material examined: MHNG-INVE-86236; Chile, Región de Antofagasta, Taltal, -25.38333° -70.51667°, 12-20 m, coll. D. Schories, lot #24; 24.04.2012; a 1.8 cm high, male colony (holotype). – MHNG- INVE-86237; Chile, Región de Antofagasta, Taltal, -25.38333° -70.51667°, 12-20 m, coll. D. Schories, lot #25; 22.04.2012; a 1.6 cm high, male colony (paratype). Description: Colonies arising from creeping, branching stolon. Stems erect, up to 1.8 cm high, monosiphonic; basal part very short and ahydrothecate, either smooth or with up to 4 annuli; remainder of stem slightly geniculate, divided into short internodes by means of inconspicuous constrictions of the perisarc; a hydrotheca to the distal end of each internode. Side branches, when present (up to 3 per stem), short and arising irregularly from below a stem hydrotheca, either in front or the rear side of the colony; occasionally, the branches arise from within the stem hydrothecae; up to 2nd order branching observed. Hydrothecae biseriate, alternate, fusiform, adnate for about 2/3rd their length to the corresponding internode; free adaxial wall with about 3 transverse ridges prolonged abaxially; abaxial wall slightly concave, aperture expanding below rim, and perpendicular to long axis of the theca; margin with 4 equally-developed, triangular cusps separated by rounded, moderately-deep embayments; a 4-flapped operculum; 3 internal, submarginal cusps (2 latero-adaxial, 1 abaxial), not always noticeable. Gonothecae (only male known) originating from below the hydrothecal bases; ovoid-fusiform, walls with 6-7 transverse ridges, aperture surrounded by 4 perisarc projections. Dimensions: Internodes 340-490 μm long and 170- 210 μm wide at nodes. Hydrothecal free adaxial length 345-380 μm, adnate adaxial length 230-270 μm, abaxial length 485-515 μm, maximum width 250-270 μm, diameter at aperture 210-230 μm. Male gonotheca 1440-1660 μm long and 575-620 μm wide. Remarks: The gonotheca of this species is illustrated by Galea et al. (2014, fig. 7C). Distribution: Chile – Región de Antofagasta [Bahía de Tocopilla (Leloup, 1974, as S. geniculata), Taltal (Galea et al., 2014)]., Published as part of Horia R. Galea, Dirk Schories, Verena Häussermann & Günter Försterra, 2017, Taxonomic revision of the genus Sertularella (Cnidaria: Hydrozoa) from southern South America and the subantarctic, with descriptions of five new species, pp. 255-321 in Revue suisse de Zoologie 124 (2) on pages 272-273, DOI: 10.5281/zenodo.893519, {"references":["Galea H. R., Schories D., Forsterra G., Haussermann V. 2014. New species and new records of hydroids (Cnidaria: Hydrozoa) from Chile. Zootaxa 3852 (1): 1 - 50.","Leloup E. 1974. Hydropolypes calyptoblastiques du Chili. Report no. 48 of the Lund University Chile Expedition 1948 - 1949. Sarsia 55: 1 - 61.","Hincks T. 1874. On deep-water Hydroida from Iceland. Annals and Magazine of Natural History (4) 13 (74): 146 - 153.","Alder J. 1857. A catalogue of the zoophytes of Northumberland and Durham. Transactions of the Tyneside Naturalists' Field Club 3 (2): 93 - 162."]}

Sertularella vervoorti El Beshbeeshy, 2011 Fig. 18E; Table 27 Sertularella vervoorti El Beshbeeshy, 2011: 151, fig. 48. – Watson & Vervoort, 2001: 167, fig. 9. – Soto Àngel & Peña Cantero, 2015: 996, fig. 7J-K. Sertularella cylindritheca. – Vervoort, 1972: 126, fig. 39A. – Stepanjants, 1979: 90, pl. 14 fig. 5A [non Sertularella cylindritheca (Allman, 1888) = Sertularelloides cylindritheca (Allman, 1888)]. Material examined: ZMH C11552; FRV Walther Herwig, Stn. 327, Argentine Shelf, off Provincia de Santa Cruz, -51.18333° -56.95000°, 225 m; 29.06.1966; sterile, fragmentary colony (fragments 0.5-1.5 cm long) [material studied by El Beshbeeshy (2011)]. Description: Erect, though flaccid, up to 3.5 cm high colonies arising from creeping stolon. No definite main stem, the original stem branching several times subdichotomously; whole colony monosiphonic in habit. Both stems and branches divided into long, curved, slender internodes through distinct, oblique nodes; a hydrotheca, or a hydrotheca and one or two lateral, indistinct apophysis(es) immediately below its base; lower order branches arising not laterally, but almost perpendicular (in front or rear side) from their higher order counterparts. Hydrothecae strongly shifted to one side of the colony; very large, tubular, adnate to the corresponding internode for only a short part of their adaxial length, then curving outwards; abaxial wall almost straight for most of its length, slightly expanded below aperture; free adaxial wall gently curving basally, then straight; perisarc thin and smooth throughout; margin with 4 small, pointed cusps separated by shallow, semicircular embayments; renovations occasional; a 4-flapped operculum; hydranths with 18-20 filiform tentacles. Gonothecae arising from below the hydrothecal bases; elongated-ovoid, tapering basally, walls transversely-wrinkled; aperture distal, large, 4-cusped, and provided with a 4-flapped operculum. Dimensions: See Table 27. Remarks: The gonothecae of this species were described by Watson & Vervoort (2001), and subsequently found by Soto Àngel & Peña Cantero (2015). Distribution: Argentina – Provincia de Buenos Aires [scattered records from offshore waters (El Beshbeeshy, 2011)]; Provincia de Tierra del Fuego, Antártida e Islas del Atlántico Sur [off the NE coast of Isla de los Estados (Vervoort, 1972, as S. cylindritheca)]. Falkland Is. – off the NE coast (El Beshbeeshy, 2011). Scotia Arc – Burdwood Bank, South Georgia (Soto Àngel & Peña Cantero, 2015). Tasmanian seamounts (Watson & Vervoort, 2001)., Published as part of Horia R. Galea, Dirk Schories, Verena Häussermann & Günter Försterra, 2017, Taxonomic revision of the genus Sertularella (Cnidaria: Hydrozoa) from southern South America and the subantarctic, with descriptions of five new species, pp. 255-321 in Revue suisse de Zoologie 124 (2) on pages 307-309, DOI: 10.5281/zenodo.893519, {"references":["El Beshbeeshy M. 2011. Thecate hydroids from the Patagonian shelf (Coelenterata, Hydrozoa, Thecata). Edited by G. Jarms. Verhandlungen des Naturwissenschaftlichen Vereins in Hamburg 46: 19 - 233.","Watson J. E., Vervoort W. 2001. The hydroid fauna of Tasmanian seamounts. Zoologische Verhandelingen, Leiden 334: 151 - 187.","Soto Angel J. J., Pena Cantero A. L. 2015. On the benthic hydroids from the Scotia Arc (Southern Ocean): new insights into their biodiversity, ecology and biogeography. Polar Biology 38 (7): 983 - 1007.","Vervoort W. 1972. Hydroids from the Theta, Vema and Yelcho cruises of the Lamont-Doherty geological observatory. Zoologische Verhandelingen, Leiden 120: 1 - 247.","Stepanjants S. D. 1979. Gidroidy vod antarktiki i subantarktiki. In: Rezul'taty biologicheskikh issledovanii sovetskikh antarkticheskikh ekspeditsii, 6. Issledovaniya Fauny Morei 22 (30): 1 - 99.","Allman G. J. 1888. Report on the Hydroida dredged by H. M. S. Challenger during the years 1873 - 76. Part II. - The Tubularinae, Corymorphinae, Campanularinae, Sertularinae and Thalamophora. Report on the Scientific Results of the Voyage of H. M. S. Challenger during the years 1873 - 76, Zoology 23 (70): 1 - 90."]}