Oceanic Amoebae from the North Atlantic: Culture, Distribution, and Taxonomy

Publisher Website
Google Scholar
Abstract
Amoebae were cultured from 43 of 49 samples taken from 19 stations in North Atlantic waters: 4 samples from Narrangansett Bay, Rhode Island [USA]; 20 samples between Rhode Island and Spain (R/V Trident cruise 170); and 25 samples from the open ocean waters of the Straits of Florida (R/V Gilliss cruise 7603). Both surface microlayers and subsurface samples were obtained. Particulate matter was concentrated and dilutions cultured in artificial sea water with OZR agar plugs. An average of 33.6 amoebae/l were found in the surface microlayer samples (equal to 1413 organisms/l, assuming their association with a 5 .mu.m-thick surface layer and a 70% collection efficiency), while subsurface water contained an average population of 1.4 organisms/l to a depth of 3090 m. The surface microlayer had a higher number of species isolated/sample than subsurface samples. Clydonella, Acanthamoeba and Platyamoeba were the most frequently encountered genera in both oceanic samplings. Narrangansett Bay samples showed a greater diversity of species than those from the Straits of Florida and trans-Atlantic stations. For the surface microlayer samples from all 3 sample sets, there were no significant differences in the numbers of amoebae/l. The subsurface values for the trans-Atlantic samples were significantly lower than those for either the Straits of Florida or Narrangansett Bay. There was an inverse relationship between numbers of amoebae and dissolved O2 in subsurface samples, and a positive correlation of amoebae with particulate ATP in the surface microlayer.