Diversity and aggregation areas of planktonic cnidarians of the southern channels of Chile (Boca del Guafo to Pulluche Channel)

Abstract

We identified 36 species of cnidarians (27 hydromedusae, 9 siphonophores) collected from the Moraleda, King, Darwin, and Pulluche channels, located in southern Chile. The hydromedusae Gossea brachymera, Hybocodon unicus, and Sarsia coccometra, and the siphonophores Rosacea cymbiformis and R. plicata were recorded for the first time in the southern channels. Diversity values were higher for Hydromedusae (2.66 bits) than for Siphonophorae (1.15 bits). The largest aggregates were found in the Moraleda and Pulluche channels, with densities that exceeded 7,000 ind•1000 m-3. The vertical distribution of the dominant species showed Solmundella bitentaculata to be located near the surface (0-20 m), whereas Sphaeronectes gracilis, Muggiaea atlantica, Clytia simplex, and Proboscidactyla ornata were found in subsurface waters (20-50 m) and Amphogona apicata in deeper waters (50-100 m). According to the Pearson analysis, salinity correlated positively with S. gracilis and S. bitentaculata and negatively with P. ornata. C. simplex was indirectly associated with temperature and the dissolved oxygen concentration.

Seasonal and vertical distribution of medusae in Aysen region, southern Chile

“…Thirty jellyfish species were recorded at the Aysén region, which involves the area between the Boca del Guafo and the Elefantes Fjord, a quantity very similar (30 species) to that recorded in the same area in spring 2002 and 2003 (Table 4; Palma et al, 2007aPalma et al, , 2007b. Seven out of the total species identified correspond to new records for the study area (Bougainvillia macloviana, Hybocodon chilensis, Hydractinia tenuis, Laodicea pulcra, L. undulata, Modeeria rotunda and Chrysaora plocamia) ( Table 1).…”

“…and Solmundella bitentaculata (Villenas et al, 2009a;Palma et al, 2011). In Aysén region, the available data exclusively involve spring and indicate the presence of 31 species, with a dominance of Amphogona apicata, Clytia simplex, Lizzia blondina (= Hydractinia minuta), Proboscidactyla ornata and Solmundella bitentaculata (Palma et al, 2007a(Palma et al, , 2007b. These regions are separated by the Boca de Guafo (43º39'S), which corresponds to the main water exchange route between the Pacific Ocean and the inner water ecosystem.…”

“…On one hand, the northern microbasin is about 250 m deep, and communicates with the adjacent Pacific through the Boca de Guafo, where more saline waters penetrate and mix with less saline waters coming from precipitations, rivers, and glacial contributions (Palma & Silva, 2004;Palma et al, 2007aPalma et al, , 2007bSilva & Palma, 2008). This constant exchange has allowed the entry of oceanic planktonic species that have successfully colonized the inner waters (Palma, 2008).…”

“…The phylum Cnidaria has been widely studied in the Chiloé region (Galea, 2007;Galea et al, 2007;Palma et al, 2007aPalma et al, , 2007bPalma et al, , 2011Villenas et al, 2009a), which is characterized by high biological production reflected on high values of chlorophyll-a (González et al, 2011) and zooplanktonic biomass, mainly supported by copepods, euphausiids and carnivorous jellyfish (Palma & Silva, 2004). In this area, strong seasonal fluctuations have been established in jellyfish abundance in winter and spring, observing 33 species with a summer dominance of Amphogona apicata, Bougainvillia muscoides, Clytia simplex, Cunina peregrina, Hydractinia tenuis, Obelia spp.…”

Species of Lensia (Cnidaria: Hydrozoa: Siphonophorae) from southeastern Brazilian waters

“…In South America, it occurs in the Pacific Ocean, in Chile, from 33°S (Valparaíso) to 55°S (Cape Horn) (lelouP 1932, PalMa 1973, 1994, PalMa & rosales 1997, PalMa et al 1999, 2007, ulloa et al 2000, PalMa & aravena 2001, villenas et al 2009); and in the Atlantic Ocean, off French Guiana (lelouP & HenTscHel 1935), from Brazil to Argentina, from 0° to 60°S (lelouP 1934, lelouP & HenTscHel 1935, alvariño 1968, 1971, 1981, nogueira & oliveira 1991, PugH 1999, MigoTTo et al 2002, silveira & Morandini 2011, and East of Falklands (Malvinas) Islands (Hardy & gunTHer 1935).…”