Study of marsh foraminifera from the coastal plain of Buenos Aires (Argentina) and its ecological implications

ANGÉLICA BALLESTEROS PRADA; BERNASCONI EMILIANA

ZOOTAXA

MAGNOLIA PRESS

Lugar: Auckland; Año: 2019 vol. 4560 p. 522 - 540

1175-5326

The objective of this work was determinate the diversity and abundance of benthic foraminifers from recent sediments ofChannel 15, Samborombón Bay (35º57´?35º58´S and 57º25´?57º22´W). From this analysis, we identified 31 speciesgrouped within 17 genera. The assemblages were composed mainly of hyaline and agglutinated forms characterized byElphidium aff. poeyanum, Elphidium gunteri, Ammonia parkinsoniana, Arenoparella mexicana and Trochammina inflata,reflecting an environment of marsh or floodplain. The foraminifer?s tests were generally well preserved, with morphologiesthat indicate predominantly epifauna and epifauna-infauna. The present work shows that despite having a general faunacharacteristic of these environments, there are small microenvironments that are characterized by the state ofpreservation, diversity and abundance of the found specimens. In that context, three associations were recognized; A,dominated by Astrononion sp.1 that was registered in the central part of the channel; association B, characterized mainlyby E. aff. poeyanum that was founded in the internal and external areas of the channel and association C, characterized bya considerable increase of mentioned agglutinated species (close to 50%) registered in the center of the channel. This studyrepresents one of the first contributions on the distribution of foraminifera and their ecological characteristics from recentsediments in Samborombón Bay