Abstract Common inhabitants of Antarctic and Subantarctic rocky shores, the limpet genus Nacella , includes 15 nominal species distributed in different provinces Southern Ocean. The Magellanic Province represents area with highest diversity genus. Phylogenetic reconstructions showed an absence reciprocal monophyly high levels genetic identity among this therefore imply a recent diversification southern South America. Because most these taxa coexist along their distribution range clear...

Patagonia extends for more than 84,000 km of irregular coasts is an area especially apt to evaluate how historic and contemporary processes influence the distribution connectivity shallow marine benthic organisms. The true limpet Nacella magellanica has a wide in this province represents suitable model infer Quaternary glacial legacy on This species inhabits ice-free rocky ecosystems, narrow bathymetric range consequently should have been severely affected by recurrent cycles during...

Diversity, abundance and composition of taxonomic groups in the Southern Ocean differ from elsewhere planet, since biogeography this region refl ects complex interactions tectonics, oceanography, climate biological elements Eocene.Several marine benthic organisms exhibit high levels genetic divergence among provinces region, supporting existence a vicariance process through plate while other with dispersive capacity recent processes.Moreover, discovery non-Antarctic decapod larvae Antarctic...

Smooth-shelled blue mussels of the Mytilus edulis species complex are widely distributed bivalve molluscs whose introductions threaten native marine biodiversity (non-indigenous – NIS). The aim present study was to identify and hybrids in Magellan Region (southern Chile). Results indicate that three mussel found region M. edulis, chilensis (or Southern Hemisphere lineage galloprovincialis), galloprovincialis Northern origin. For first time, alleles introduced trossulus reported from...

Major geologic and climatic changes during the Quaternary exerted a major role in shaping past contemporary distribution of genetic diversity structure aquatic organisms southern South America. In fact, northern glacial limit along Pacific coast, an area environmental terms topography, currents, water salinity, represents biogeographic transition for marine freshwater species. We used mitochondrial DNA sequences (D-loop) to investigate consequences cycles over pattern G. maculatus (Pisces:...

Abstract The upper sublittoral benthic macrobiota off central Chile (36° 32'S) was sampled on six cruises during 1984 and 1985, at four fixed stations. aim of this study to learn about bathymetric seasonal patterns ofdistribution abundance macrobenthos, including the macroinfauna sulfur bacteria Thioploca spp., their relationship oceanographic variables, in particular, dissolved oxygen. Biotic data were analyzed by different approaches methods, community attributes, diversity indices,...

We analysed the biodiversity of ascidians in two areas located southern and northern Chile: Punta Arenas Strait Magellan (53o latitude, subantarctic) Coquimbo (29o temperate). The oceanographic features zones are markedly different, with influence Humboldt Current north, Cape Horn System, together freshwater influxes, Magellanic zone. Both regions were surveyed twice during 2013 by SCUBA diving pulling ropes aquaculture cages. artificial structures natural communities sampled. A total 22...

A benthic megafaunal study off Concepción Bay, central Chile (36°32'S, 73°W), provided abundance and bathymetric distribution data of the newly recruited squat lobster Pleuroncodes monodon (Decapoda, Galatheidae). The megafauna was surveyed 8 times between July 1991 April 1992, with an Agassiz trawl at depths 40, 64, 96 m along a transect across continental shelf. Recruits P. (carapace length (CL) 3-10 mm) were first sampled in all depth strata early March, then April. density (1 ind/m2)...

Sterechinus neumayeri is an abundant regular sea urchin that lives in the shallow Antarctic waters. This organism has been used as a model system many fields of biology. Yet, understanding evolutionary identity species, such its phylogenetic relationships and divergence time, remains limited. Here, we reconstructed molecular phylogenies species together with two southernmost South America ( Loxechinus albus Pseudechinus magellanicus ), parechinid Paracentrotus lividus ) three...

We studied the ascidian fauna from two zones located in subantarctic (Punta Arenas, latitude 53º) and temperate Chile (Coquimbo, 29º). The different oceanographic features of zones, with influence Humboldt Current north Cape Horn System freshwater inputs south, led to markedly faunas. A total 22 species were recorded, no shared across areas (11 each). new Polyzoa iosune is described, Lissoclinum perforatum found for first time Pacific Ocean, Synoicum georgianum minor are Chilean fauna....

This paper analyzes the composition, abundance and biogeographical relationship of benthic polychaetes collected in three shallow subtidal locations (mouth Cuervo Condor rivers Acantilada Bay) from Aysen Fjord, AF, Chile (45ºS, 73ºW), provides a comparison with data on soft-bottom Antarctica other Magellan Province: Dalcahue Channel, DC (42º22´S, 73º39´W), Puerto Cisnes, Puyuhuapi PC (44º43´S, 72º42´W) Straits, MS. AF polychaete fauna comprises 38 species, macrobenthic taxon being most...

Underwater photographic records and sampling were carried out in Steamer Bay, Strait of Magellan, Chile, to study the spatial distribution patterns juvenile king crabs Lithodes santolla during late winter early spring 2006.Observations made on relationship between these holdfasts stipes large kelp Macrocystis pyrifera.Dense aggregations, known as "pods", crab (34-75 mm CL) observed photographed for first time specific areas embayment relation Macrocystis; pod abundance varied 2 70 ind•m -2...

Resumen.-El isópodo parásito Pseudione tuberculataRichardson, 1904 infesta la cavidad branquial de especies familia Lithodidae en el extremo sur Sudamérica.Ha sido descrito previamente como Neolithodes Archipiélago los Chonos, Chile, y Paralomis granulosa (Jacquinot, 1847) Lithodes santolla (Molina, 1782) aguas someras del canal Beagle

Field and laboratory study of egg masses, encapsulated development stages early-hatched veliger larvae the sub-Antarctic observations Fusitriton magellanicus (Röding, 1798) are described from samples collected in Magellan Strait (Santa Ana Point: 53º38'15"S, 70º54'38"W), Chile, between 2005 2006. We aimed to determined if: i) if these gastropod shows a reproductive pattern similar low-latitude ranellids, with respect other locations within Gondwanian distributional range (Australia, New...

Abstract Egg-laying behaviour, egg masses and intracapsular development of the ranellid snail Argobuccinum pustulosum are described here. Snails were collected by diving, at Corral Bay (39°53′S; 73°25′W) in south Chile, adult individuals reared tanks with circulating seawater ambient temperature to obtain their masses. The spawn produced is an irregular flat mass, taking between 3 9 days for females complete deposition. Peduncleless tube-shaped capsules 9–12 mm length, amounted 47–149 per...

We describe the presence of bivalve Modiolarca lateralis (Say, 1822) in six tropical ascidians Ascidia curvata, A. sydneiensis, panamensis, interrupta, Herdmania pallida and Polycarpa spongiabilis collected at depths 1-3 m on coral reefs, mangrove roots dock supports Almirante Bay, Bocas del Toro, Panama (9o18'N, 82o13'W) during June-July 2011. Bivalve prevalence varied between 9-30% across species, but was mainly associated with P. interrupta. Prevalence seems to be influenced by tunic...

This paper describes the spatial and seasonal dynamic of population spionid polychaete Scolecolepides uncinatus Blake 1983 from a sandy-muddy intertidal located in an embayment with megatidal regime at Lomas Bay, Tierra del Fuego, Magellan Strait, Chile (52°40' S, 69°15' W).In order to test trophic importance this polychaete, abundance distribution was studied July-August, 2007 (winter; -2 °C) January 2008 (summer; 17°C 23 °C).At both seasons, three transects near 2 km length were...

Chile*Environmental monitoring index based on the temporal fluctuations in abundance of two species benthic polychaetes from Quintero Bay, Chile

A benthic community constituted by an assemblage of at least four species deep-sea corals collected in only one trawl carried-out on the summit O'Higgins I seamount, central Chile. The were during a Chilean-Japanese cruise onboard R/V" Koyo Maru" December 29, 2004. Presence oxygenated and cold Antarctic Intermediate Water (>400 m depth) plateau was recorded under Equatorial Subsurface associated to oxygen-minimum zone (OMZ, <1 mL O 2 L -1 ). biogeographic origin fauna evidenced mix...