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Heterotrophic flagellates and other protists associated with oceanic detritus throughout the water column in the mid North Atlantic

Authors:
  • Maple Ferryman

Abstract

Heterotrophic protists, mostly flagellates, encountered in association with marine detritus from various collections in the mid North Atlantic are described. About 40 species have been identified and are reported. Taxa reported here for the first time are: Caecitellus gen. nov. (Protista incertae sedis) and Ministeria marisola gen. nov., sp. nov. (Protista incertae sedis). The flagellates form a subset of the community of heterotrophic marine flagellates encountered in more productive marine sites. Most species are bacterivorous and small. The community extends to the ocean floor but the diversity is reduced in samples taken from greater depths. The decline in species diversity is linked also to a decline in numbers of individuals. We discuss these changes in relation to food supply and pressure effects.
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... Faunistic investigations of heterotrophic flagellates and heliozoans supported with morphological descriptions were especially common in protistological literature in the 90 s -early 2000s (Larsen and Patterson 1990; Lee and Patterson 2000;Lee et al. 2003;Mikrjukov 2001;Patterson and Simpson 1996;Patterson et al. 1993;Tong 1997b, c;Vørs 1992). At present, such studies are relatively rare and have been largely replaced by molecular surveys from bulk microbial community DNA (Geisen et al., 2019;Pawlowski et al., 2016). ...
... Distribution: Marine waters of Australia (Tong et al. 1998), Brazil (Larsen and Patterson 1990), U.K. (Patterson et al. 1993;Tong 1994Tong , 1997c. ...
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... Well-marked 608 ingestion organelle with two gradually narrowing rods extends along entire cell length. Nucleus (Patterson et al. 1993;Tong 1994Tong , 1997c. 652 Skuja, 1948 c (Fig. 5n, o) Cell length is 4.5-5.5 μm, cell width is 3.8-5.5 μm. ...
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