Distribución latitudinal de foraminíferos bentónicos (Protozoa: Foraminiferida) a nivel de subórdenes y familias, en canales y fiordos patagónicos chilenos

Abstract

The latitudinal distribution of benthic foraminifers is studied at the levels of suborder and family. 106 samples were collected on the continental shelf (50-300 m) between 43°S and 55°S in the area of channels and fjords, eastern South Pacific, during Cimar Fiordos Expeditions 2, 3, 7 and 8. The foraminifers (50,480 specimens) were classified in 5 suborders, 46 families and 228 species. The number of suborders, families, and the families by suborder do not depend on the latitudinal gradient. Likewise, abundance at the suborder and family levels does not fluctuate with latitude. A major change was observed at 44°S (Baeza and Memory channels), where the number and abundance of suborders and families, species richness, and diversity decreased drastically. The same occurred between 46° and 48°S (Steffen and Mitchell estuaries and Escape channel). This may suggest that local events, such as oceanic currents, could be more important than latitude in controlling microfauna distribution patterns. © 2006 Escuela de Ciencias del Mar Pontificia Universidad Católica de Valparaíso.