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22
12 • "PROTIST—2016
plankton biomass has also increased 1.9 and 1.3 times, respectively. Along with these changes, a redistribution of the total biomass of the plankton community has occured between the pelagic and littoral parts. In the pelagic zone of the lake the increase was most significant, 3.8 times, and in the littoral zone it amounted 1.3 times. The share of protists in the unicellular plankton biomass in the pelagic zone remained unchanged, while in the littoral zone it increased 2.3 times. Protist's contribution into the total plankton biomass in the pelagic zone increased 1.3 times, and in the littoral 3.4 times. These changes were mainly related to the increased role of the cryptophytes, dinoflagellates and ciliates, especially mixotrophic. In the context of eutrophication the most significant correlations of individual groups ofprotists were registered with the concentrations of phosphorus, ammonia nitrogen and chlorophyll a. The influence of environmental factors on the peculiarities ofprotist distribution and ratios of their groups are discussed.
IOTANEMA SPIRALE GEN. ET SP. NOV., A NEW ENDOBIOTIC LINEAGE OF FORNI-CATA WITH STRIKINGLY SIMPLIFIED MORPHOLOGY AND ULTRASTRUCTURE Cepicka I.1, Yubuki N.1, Zadrobilkova E.12
1 - Department of Zoology, Charles University in Prague, Vinicna 7, 128 44 Prague 2, Czech Republic
2 - Centre for Epidemiology and Microbiology, National Institute of Public Health, Srobarova 48, 100 42 Prague, Czech Republic [email protected]
Fornicata is a lineage of excavates living in low oxygen environments and lacking a conventional mitochondrion. Three main morphological/ecological subgroups of Fornicata are recognized: free-living Carpediemonas-like organisms (CLOs) from marine habitats and two parasitic/commensal lineages living in animal hosts, retortamonads and diplomonads. The research of Fornicata centers on evolutionary perspectives such as transition from free-living lifestyle to parasitic one and mitochondrion transformation. Nonetheless, current modest knowledge of the biodiversity of Fornicata limits our ability to draw the whole picture of evolutionary history of this group. The free-living CLOs are particularly important due to the plesiomorphic traits of excavates. In this study, we cultured a novel member of Fornicata, Iotanema spirale gen. et sp. nov., isolated from fresh feces of a gecko. I. spirale exhibits several unique features not seen among fornicates. It possesses a single flagellum and a highly reduced cytoskeletal system with a single microtubular root, two fibers, and
dorsal fan; the excavate ventral groove is missing. SSU rRNA gene analyses demonstrated that I. spirale branches as a sister lineage to the free-living CLO Hicanonectes teleskopos and its relatives, which means that it represents the third known endobiotic lineage of Fornicata.
SPATIOTEMPORAL DISTRIBUTION OF SPECIES DIVERSITYAND COMMUNITY STRUCTURE OF CILIATES IN INTERTIDAL SANDY SEDIMENTS OF HUOKUN'AO BEACH, NANJI ISLANDS (EAST CHINA SEA, CHINA) Chen X.1, Chen W.2, Cai H.2, Xu K.1
1 - Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
2 - Nanji Islands National Marine Nature Reserve Administration, Pingyang 325401, China [email protected]
In intertidal sediments, ciliates are a highly diverse and quantitatively dominant group, whose community structure, in some sense, may reflect the condition of environmental quality. We investigated the spatiotemporal distribution of species diversity and community structure of ciliates in the intertidal sandy sediments of Huokun'ao beach, Nanji Islands National Marine Natural Reserve based on sample collections in November 2013 (autumn), February (winter), May (spring) and August (summer) 2014. The results showed highly diverse and abundant ciliates in the intertidal sediments of the beach, where a total of 148 species representing 19 orders and over 70 genera were identified. The abundance and species composition of benthic ciliates showed significant correlation with seasons and sediment depths. Bacterivorous ciliates constituted the most abundant group, followed by carnivores and algivores. The predominance of bacterivores indicated that the ciliate community in the intertidal sediment of Huokun'ao was not a typical interstitial ciliates fauna, but a pattern similar to those in muddy sand sediments with high level of organic matter. This is likely a subsequent effect oflong-term human activities. In spite of the impact, the high diversity of ciliates indicates that the benthic environment in the Huokun'ao beach and its surrounding area is in fair condition, which is attributed to the biodiversity conservation measures adopted, e.g. the relocation of surrounding residents and facilities.
PROKARYOTIC ENDOCYTOBIONTS OF PELOMYXIDAE
Chistyakova L.V.1, Berdieva M.A.2, Kostygov A.Yu.34, Frolov A.O.3
1 - Centre of Core Facility of SPSU "Culturing
