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Protistology ■ 37
2 - Shirshov'Institute ofOceanology, Russian Academy
of Sciences, Russia
The results of the species composition, abundance and biomass of heterotrophic nanoflagellates (HNF) were obtained for the first time in the Laptev Sea in August-September 2014-2015. An attempt was made to assess the role of HNF in grazing productions of bacterioplankton (PB) and virioplankton (PV). 24 species and forms of HNF 9 taxa and groups of uncertain systematic position were found. Kinetoplastea Honigberg, 1963 were characterized by the highest species diversity. The HNF community dominated by bacteriophages (eighteen species), also found four omnivorous and two carnivorous species. Nhnf ranged from 108-651 cells/ml, the biomass — 0.3-3.5 mg C/m3. NHNF was three orders of magnitude lower than NB, and BHNF was 1.6-63.3% (mean 24.4+4.0%) biomass of bacterioplankton. Between NHNF and NB were detected high positive correlation (R=0.63, p=0.05). The virus particles (diameter of 200-531 nm) potentially can be edible objects for HNF. However, the ratio of the number of large viruses at NHNF was low - 42-417. HNF could consume a significant amount of virus attached to the walls and inside bacteria. The number of bacteria with attached viruses was 8.7-26.5% NB. On bacteria it was up to 11 virus particles. The number ofbacteriophage-viruses in infected cells reached 111 particle/cell. Guided by literature data on clearance rates of water by Arctic HNF (Sherr et al., 1997), calculated that in the water column of the Laptev sea the HNF community consumed 1.1-30.4% (average 8.3%) daily PB and 1.3-77.2% (average 14.9%) the daily PV. The research supported by the RFBR grant 14-04-00130.
THE STATUS OF THE SPECIES BALANTI-DIUM ELONGATUM FROM THE GUT OF EUROPEAN COMMON FROG Kornilova O.A.1, Chistyakova L.V.2, Kostygov A. Yu.34
1 - Herzen State Pedagogical University of Russia, St. Petersburg
2 - Centre of Core Facility of SPSU "Culturing collections of microorganisms", St. Petersburg, Russia
3 - Zoological Institute of the Russian Academy of Sciences
4 - Life Science Research Centre, Faculty of Science, University of Ostrava
The representatives of the genus Balantidium Clapare de et Lachmann, 1858 have several common morphological features: sacciform or
slightly elongated body completely covered with cilia forming dense longitudinal rows. In the anterior part of the body, there is an opening of vestibulum. Such features are clearly visible under light micro-scope. Because balantidia have very few other morphological characters suitable for taxonomy, their species identity is usually determined using morphometric data. Comparative analysis of several described Balantidium spp. indicated that many of these specific names might be synonyms. All balantidia inhabiting the intestine of mammals and birds were recognized to belong to a single species — Balantidium coli, recently moved to the genus Balantioides Alexeieff, 1931. We supposed that some species from amphibians may be synonyms (balantidia are polymorphic) and some of them may belong to different genera. For solving this issue, we used modern electron microscopic techniques and molecular phylogenetic analysis. We studied the morphology of Balantidium entozoon and B. elongatum from the gut of European common frog Rana temporaria Linnaeus, 1758 using light and electron microscopy. The distinguishing features of B. elongatum are the long thin fusiform body and relatively short vestibulum. However, other traits (number of kinetes and the distance between them) are indistinguishable between two species. Their intracellular structures also showed no differences. The sequences of 18S rRNA gene of both species were identical to each other and to that of B. entozoon from the GenBank. Thus B. elongatum must be considered as a younger synonym of B. entozoon.
BRIDGING THE GAP BETWEEN TRADITIONAL TAXONOMY AND TRANSCRIP-TOMICS IN ARCELLINIDS (AMOEBOZOA) Kosakyan Anush1, Brown Matthew W.2 3, Lara Enrique4, Mitchell Edward A.D.45, Lahr Daniel J.G.1
1 - Laboratory of Evolutionary Protistology, Institute of Biosciences, University of Sao Paulo, Matao, Travessa 14,Cidade Universitaria, 05508-090 - Sao Paulo, SP, Brasil
2 - Department ofBiological Sciences, Mississippi State University, Mississippi State, 39762, Mississippi, USA
3 - Institute for Genomics, Biocomputing and Biotechnology, Mississippi State University, Mississippi State, 39762, Mississippi, USA
4 - Laboratory ofSoilBiology, University ofNeuchatel, Rue Emile-Argand 1, 2000 Neuchatel, Switzerland
5 - Jardin Botanique de Neuchatel, Chemin du Perthuis-du-Sault 58, 2000Neuchatel, Switzerland. [email protected]
38 • "PROTIST—2016
Arcellinid testate amoebae are a diverse group of terrestrial and freshwater microbial Eukaryotes. Described by naturalists since the eighteenth century, Arcellinids are frequently used in biomonitoring and paleo-ecological reconstruction of past climates. They are supposed to include the oldest undisputed eukaryotic fossils, which vests them with a particular importance in the study of basal nodes of eukaryotic tree. However, difficulties in culturing these organisms as well as in the application of molecular biology protocols have limited the study oftheir diversity and evolutionary history. Our aim in this study was to investigate arcellinid (Amoebozoa, Tubulinea) diversity, and to recon-struct a solid and precise phylogeny combining comprehensive taxon sampling, multiple genes and detailed morphological characterisation. We obtained transcriptomes for twenty-one testate amoeba species, for most of which no molecular data was yet available. Our phylogenetic reconstruction of Arcellinids is based on the combination of morphological data and molecular data on about 350 genes and 100 000 amino acid positions.
HETEROTROPHIC FLAGELLATES IN THE WATER COLUMN AND BOTTOM SEDIMENTS IN THE RYBINSK RESERVOIR Kosolapova N.G., Kopylov A.I., Kosolapov D.B. Papanin Institute for Biology of Inland Waters, Russian Academy of Sciences, Borok, Yaroslavl obl, 152742 Russia [email protected]
A total of 56 heterotrophic flagellates (HNF) from 15 large taxa were identified in water and bottom sediments of the large floodplain mesoeutrophic Rybinsk Reservoir during the summer period. Among them 35 species were detected in plankton and 45 species were found in benthos. Twenty-four species of HNF were common for these two habitats that constituted 44% of their composition. Ten species were recorded only in plankton and 20 species were recorded only in benthos. The orders Chrysomonadida, Euglenida and Cercomonadida differed, to a greater extent, in the species composition in water and bottom sediments. Most of the species of heterotrophic flagellates which were found in the Rybinsk Reservoir were bacteriotrophs. Three predatory species were also found. The abundance and biomass of HNF in the water column averaged 991 ± 326 cells/mL and 41.4 ± 14.1 mg/m3, respectively in the water column and (236 ± 61) x 103 cells/mL and 10.7 ± 4.0 pg/mL, respectively in bottom sediments. The average
values of the abundance and biomass of benthic heterotrophic flagellates were 238 and 259 times, respectively higher than in plankton. The biomass of flagellates constituted on average 11.2% of the bacterial biomass in the water column and only 0.8% in bottom sediments. The estimation of the role of flagellates in the consumption of the bacterial production demonstrated that HNFs were an important factor which regulated the bacterioplankton development grazing on average 32.3% ofits daily production whereas their effect on bacteriobenthos was insignificant as they consumed only 2.0% of its production. The moderate positive correlation (r = 0.33) and (r = 0.52), respectively was found between the abundance and biomass of bacteria both in plankton and benthos.
MINIONS OF GREAT CTHULHU AWAKENING - A NEW INSIGHT INTO THE DIVERSITY OF PARABASALID SYMBIONTS OF COCKROACHES
Kotyk Michael, Varadinova Zuzana, Cepicka Ivan Department ofZoology, Charles University in Prague, Vinicna 7, 128 44 Prague 2, Czech Republic [email protected].
Parabasalian symbiots of xylophagous cockroaches from families Cryptocercidae and Isoptera (termites) have been attracting the interest of biologists for several decades; they often possess large, complex, and visually attractive cells and are of great ecological significance. Phylogenetic analyses showed that the complex forms of parabasalians (=hypermastigotes) have arisen several times independently. On the other hand, only a little attention has been paid to endosymbionts of "normal" cockroaches, although these insects show a great diversity in morphology and lifestyles. We have examined the intestines of 250 cockroaches belonging to 100 species and 20 subfamilies (out of 33), established 50 stable cultures of trichomonads, sequenced their SSU rRNA gene, and studied the morphology of some of them. Approximately one half of the obtained trichomonads formed a considerably diversified clade that contained the recently discovered hypermastigote Cthulhu with approximately 20 flagella and trichomonad genera Hexamastix and Cthylla with 6 flagella. By contrast, our strains have cells equipped with three or four. Thus, Cthulhu and Cthylla are not orphans anymore, but are surrounded by a cloud of lesser trichomonads. Most ofthe remaining strains belong to the understudied genus Hypotrichomonas, where they represent several novel species.
