Deep‐Sea Polychaetous Annelida from Central America to the Antarctic Peninsula and South Sandwich Islands

Abstract

Based on the 1958 Vema cruise and the 1965 Anton Bruun cruise 11 off the west coast of Central America and sout'h through the islands ezst of the tip of South America, 143 trawl samples were examined for abyssal polychaetous annelida. The cruise tracks designated 7 major areas: Central America (I), Ecuador-Peru (11), Central and Southern Chile (111), Chile and the Magellan Strait (IV), Tierra del Fuego (V), the Island Complex (Falkland, South Georgia and South Sandwich Islands) (VI), the Dribke Strait and Antarctic Peninsula (VII). The collections yielded 7,015 individuals and 322 species from 52 families. The relatively small number of species was attributed mainly to sampling effort, collecting gear and processing techniques.Each major area was characterized in terms of the number of individuals, the number of species, mean number of individuals, mean number of species and mean H', S R , J' and DI. Species diversity was significantly higher in Central America (I) than in the other areas. The relationships between biotic and abiotic measures (dept'h and areas of upwelling) were examined. There were no significant associations for the entire data base with depth. Moreover, there was no association between abundance of polycliaetes and areas of upwelling which was hypothesized. I n fact, relative abundance was highest in the deepest portions of Central America (I) (Guatemala Basin) and Ecuador-Peru (11) (Milne-Edwards Deep) compared to shallower areas closer to areas of upwelling. Quantitative collecting gear and refined processing techniques will be required to more accurately address these relationship?. Dominant families were identified in terms of number of sFecirs and number of individuals. These families conformed well with world wide generalizations of dominant families. Dominant, species were identified based on the Biological Index Value. The top twenty or dominant species for each major brea were identified. A number of these dominant species occurred widely throughout the mnjor areas. The dominant species for the entire data set were determined. I n general these species were very eurybathic which was consistent with other worldwide depth distributions of abyssal polychaetes.

Distribution and diversity of the Opheliidae (Annelida, Polychaeta) on the continental shelf and slope of Iceland, with a review of the genus Ophelina in northeast Atlantic waters and description of two new species

“…In contrast, Ophelina species are mainly present on deeper bottoms of the continental shelf and slope where they can become one of the most relevant faunal components (Cúrdia et al 2004;Maurer and Williams 2007;Schüller and Ebbe 2007). The knowledge of the actual diversity and ecology in this genus has improved in the last decades Hartmann-Schröder and Parker 1995;Maciolek and Blake 2006;Schüller 2008), mostly due to the study of material collected in several research projects devoted to the knowledge of the deep-sea fauna (e.g.…”

Polychaete assemblages on the Magellan and Weddell Sea shelves: comparative ecological evaluation

“…Mann-Whitney U-test for differences in density, species richness, diversity and evenness values (means ± SD) between the Magellan region (MR) and Weddell Sea ( The actual patterns derived from this study are based on 163 species and 36 families in WS, and 199 species and 37 families in MR. The latter figures represent the highest numbers of species/families reported up to now for the little studied MR. Maurer & Williams (1988) reported 76 polychaete species belonging to 33 families for the Straits of Magellan, while Cañete et al (1999) distinguished 38 species from 24 families in 39 corer samples from the northern border of MR. Bremec et al (2000) found 119 polychaete species from 34 families in the Straits of Magellan and 36 species from 20 families on the eastern Patagonian shelf in their qualitative and quantitative samples.…”

New records to Chile of the Family Paraonidae (Annelida: Polychaeta)

“…If Aedicira nr. ramosa sensu Maurer and Williams (1988) is a different species, the present records are the first for the southern hemisphere.…”

“…The Paraonidae of Chile have only very recently been reported; Rozbaczylo (1985) listed six species in three genera, recorded for Chile between 1965and 1978. Maurer and Williams (1988 and Mariani et al (1996) provided a few additional records of paraonids sampled off the Chilean coast, but they did not provide exact data on the collection sites.…”