Mariano J. Albano

Macrobenthos and multi-molecular markers as indicators of environmental contamination in a South American port (Mar del Plata, Southwest Atlantic).

We evaluated benthic habitat quality along a presumed contamination gradient in the Mar del Plata port (Southwestern Atlantic) by coupling biological and chemical proxies in a multidisciplinary approach. Organic matter and photosynthetic pigment contents were higher in silty-clay bottoms of the inner port sites. Levels of all fecal steroids decreased from the inner sites to the port inlet. High concentrations of coprostanol in the inner sites seemed to derive from a permanent population of sea lions rather than from sewage outfalls due to coprostanol/epicoprostanol ratio (IV) values <2.5. PAHs levels were also higher in the inner sector, related to both biomass combustion and petroleum combustion associated to local marine traffic. High disturbance and low ecological status were reflected in low benthic diversity and high AMBI values in the inner sites.

Macrozoobentos asociado a los agregados de Phyllochaetopterus socialis Claparède, 1870 en el puerto de Mar del Plata, Argentina

Aggregates of the polychaete Phyllochaetopterus socialis were recorded for the first time in Mar del Plata Harbour, in December 2003. These were found at about 6 m depth, on the border between the break-water rocks and soft sediments. Three random samples (monthly or bimonthly), were taken each season by SCUBA diving. We recorded 56 species belonging to 11 phyla: Porifera, Cnidaria, Nematoda, Plathyhelminta, Arthropoda, Sipuncula, Bryozoa, Annelida, Mollusca, Echinodermata, and Chordata. The highest numbers of organisms were found in summer. The most abundant taxa were crustaceans (amphipods and tanaidaceans), molluscs, polychaetes, and bryozoans. In summer, crustaceans were dominant, whereas the rest of the groups (molluscs, polychaetes and others) showed no significant differences in density along the sampling seasons. Bryozoans were the sessile organisms with the highest relative frequency. This study extends the distribution range for some species, including Hydroides plateni and Elysia patagonica, which had never been cited in Mar del Plata harbour before. The associated macrofauna aggregate was diverse.

Morphological and genetic confirmation of Jassa slatteryi (Crustacea: Amphipoda) in a harbour of Argentina

Jassa slatteryi is reported for the first time in Mar del Plata harbour, Argentina. A morphological comparison with the original description and a genetic analysis are made to corroborate the identification of specimens. The report of range expansion along the South-western Atlantic coast is discussed.

First record of Phyllochaetopterus socialis Claparède, 1870 (Annelida: Polychaeta) in Mar del Plata Harbor, Buenos Aires, Argentina

Agregados del poliqueto tubicola Phyllochaetopterus socialis Claparede, 1870 fueron registrados por primera vez en el Puerto de Mar del Plata (38°02?S; 57°31?30?W), Buenos Aires, Argentina, en diciembre de 2003 mediante buceo autonomo a 6 m de profundidad. Los agregados fueron observados sobre sustrato duro, en el limite inferior del submareal. El presente trabajo amplia el rango de distribucion de dicha especie para Sudamerica, de la cual se tienen registros confirmados unicamente para el sur de Brasil y el Rio de la Plata (Argentina).