THE TAXONOMY AND ECOLOGY OF CRITHIONINA-DELACAI SP-NOV, AN ABUNDANT LARGE AGGLUTINATED FORAMINIFER FROM EXPLORERS-COVE, ANTARCTICA

We describe Crithionina delacai, a new large (up to 6.5 mm) agglutinat ed foraminifer that differs from related species (notably C. granum) i n the composition and arrangement of particles within the test, The ne w species is abundant at a 28-m-deep site in Explorers Cove, McMurdo S ound, Antarctica. This unusually shallow-water occurrence for a specie s of Crithionina probably reflects the tranquil, cold (-1.8 degrees C) , thermally stable, and relatively oligotrophic conditions that prevai l at our study site. Crithionina delacai lives infaunally in the top 1 cm of sediment and apparently feeds on diatoms, Its abundance at dept hs accessible to SCUBA divers provides a unique opportunity to conduct detailed biological studies of this predominantly deep-sea genus.