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16 • "PROTIST—2016
Basic Research (grant nos. 14-04-00500, 14-0400554,15-29-02518).
THE CHLAMYDOPHRYIDAE REVISITED WITH SPECIAL FOCUS ON THE GENUS LECYTHIUM
Dumack Kenneth1, Baumann Christina1, Muller Marina2, Bonkowski Michael1
1 - University of Cologne
2 - Leibniz-Centre for Agricultural Landscape Research ZALF
[email protected] Although testate amoebae have attracted interest of protistologists for more than 150 years, some groups especially those with a hyaline test are still poorly known. One of those fairly understudied groups is the family Chlamydophryidae. They are difficult to culture and therefore only old, sometimes obscure, species descriptions are available. Further, no molecular data was obtained and therefore in modern mass sequencing studies they are only recognized as OTUs of unknown affinity. Nevertheless, they are widely distributed, can occur in high abundances in freshwater and terrestrial habitats, show interesting feeding behavior and have a high diversity in morphology. This talk will give an overview of the up to date knowledge on the Chlamydophryidae and will further focus on one of its genera, Lecythium that was first described by Hertwig & Lesser in 1874. We (a) established 7 cultures of 5 Lecythium species and provide detailed morphological as well as ecological observations (b) obtained SSU sequences and conducted phylo-genetic analyses of the Tectofilosida, showing that Lecythium is closely related to the Pseudodifflugiidae and splits into a terrestrial and freshwater clade and (c) performed food choice experiments that underline the mycophagous and algivorous feeding behavior of Lecythium. Our talk will show that the Chlamydophryidae are a group of protists that are highly fascinating.
THE BASE OF CERCOMONAD RADIATION IS STILL IN FOR A SURPRISE, KRAKEN GEN. NOV.
Dumack Kenneth1, Schuster Julia1, Bass David2, Bonkowski Michael1
1 - University of Cologne
2 - Department of Life Sciences, Natural History Museum London, Cromwell Road, London [email protected]
The term 'filose amoebae' describes a highly poly-phyletic assemblage of protists whose phylogenetic placement can be unpredictable based on gross
morphology alone. We isolated 6 filose amoebae from soils of two European countries and describe a new genus of naked filose amoebae, Kraken gen. nov. comprising one new species Kraken carinae sp. nov. We provide a morphological description based on light microscopy and small subunit rRNA gene sequences (SSU rDNA). In culture, Kraken carinae strains were very slow-moving and preyed on bacteria using a network of filopodia. Phylogenetic analyses of SSU sequences reveal that Kraken are core Cercozoa, branching weakly at the base of the cercomonad radiation, most closely related to Paracercomonas, Metabolomonas, and Brevimastigomonas. Kraken sequences are >99% similar to an environmental sequence obtained from a freshwater lake in Antarctica, indicating that Kraken carinae is not exclusively soil dwelling, but also inhabits freshwater habitats.
FIRST RECORD OF BROMELIOPHRYA BRA-SILIENSIS FOISSNER, 2003 (CILIOPHORA: GLAUCOMIDAE) FROM TANK BROMELIADS IN MEXICO WITH SOME NOTES ON ITS DISTRIBUTION AND ECOLOGY Durán-Ramírez C. A.1, Mayén-Estrada R.1, Ciros-Pérez J.2
1 - Laboratorio de Protozoología, Departamento de Biología Comparada, Facultad de Ciencias, Universidad Nacional Autónoma de México, Ciudad Universitaria s/n, Coyoacán, 04510Mexico City
2 - Proyecto de Investigación en Limnología Tropical. UIICSE, FESIztacala UNAM. Av. de los Barrios No. 1, Los Reyes Iztacala, Tlalnepantla 54090, Estado de México
[email protected] Bromeliophrya brasiliensis is a glaucomid bacteri-vorous ciliate described from terrestrial tank bromeliads in the Atlantic Coast of Brazil, and recorded in Paraná, Brazil and Ecuador from rupicolous bromeliads. The reduction of somatic ciliature and the presence of two kinetofragments, which migrate to the left margin of the buccal cavity, are the main cytological characteristics as compared with B. quadristicha which presents four kinetofragments and it has been recorded in the Antilles. The objective ofthis work is to describe the ciliate diversity from tank bromeliads in Mexico. We sampled 30 individuals of epiphytic tank bromeliads including five species of genera Catopsis and Tillandsia in three different temperate forest sites from Central and Southern Mexico, during the year 2015. The sites were located from 1336 to 2426 m a.s.l. Observation and identification of B. brasiliensis was performed using bright and DIC microcopy,
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and with silver impregnation methods. Cellular specific characteristics were analyzed and B. brasi-liensis was recorded in 23% of the samples with temperature values between 18 to 22 °C, and pH values from 3 to 6, demonstrating a wider range of temperature and pH tolerance, and a broad geographic distribution but only in Neotropical tank bromeliads. This is the first record for the species in these microecosystems at different altitudes in Mexico. Financial support was provided by National Council of Science and Technology (CONACYT) fellowship number 224627. Biol. Margarita Reyes and M.A. Aldi de Oyarzabal from Facultad de Ciencias, UNAM, are thanked for technical assistance and scientific illustration respectively.
PROTIST DIVERSITY AND INTERACTIONS WITHIN DEEP-OCEAN SEDIMENT AND WATER-COLUMN MICROBIAL COMMUNITIES
Edgcomb V.P.1, Pachiadaki M.12, Taylor C.1, Kormas K.Ar.3, Bernhard J.M.1, Taylor G.T.4
1 - Woods Hole Oceanographic Institution, Woods Hole, MA, USA
2 - Bigelow Laboratories, East Boothbay, Maine, USA
3 - University of Thessaly, Greece
4 - Stony BrookUniversity, Stony Brook, New York, USA [email protected]
Protists are integral members ofmarine food webs and exhibit complex relationships with other microbial taxa. Phagotrophic protists contribute significantly to carbon turnover in the sunlit ocean and evidence suggests grazing in the dark ocean can be significant as well. The molecular signatures of parasitic protists comprise significant fractions of many high-throughput sequencing datasets, suggesting a potentially important role in controlling populations oftheir host(s). Prokaryotic symbionts offree-living protists can be numerous, and, particularly in low-oxygen to anoxic marine habitats their collective metabolisms may contribute significantly to bio-geochemical cycling. Particular groups of protists are abundant and common inhabitants of marine sediment and water column oxyclines and very deep halocline habitats where physical associations with prokaryotes are frequently observed. Using open ocean oxygen minimum zones, deep hypersaline anoxic basins of East Mediterranean Sea, and the permanently stratified water column of Cariaco Basin, Venezuela as natural laboratories to link biogeochemistry and diversity, we report evidence of niche partitioning and specialized communities. Sediment communities seem to be dominated by different key players but exhibit similar niche
partitioning. Projects supported by NSF OCE-0849578, OCE-1061391, and OCE-1336082.
THE MARINE CARAVAN INVADING THE TWO BIG SEAS OF THE RED SEA AND THE MEDITERRANEAN THROUGH THE MARITIME SUEZ CANAL: I- CILIOPROTISTS Elserehy Hamed12, Al Quraishi Saleh1, Al-Farraj Saleh1
1 - Department of Zoology, College of Science, King Saud Uuniversity, Riyadh 11451, Saudi Arabia
2 - Department ofMarine Science, Faculty ofScience, Port Said University, Egypt [email protected]
Suez Canal is the main connecting link between the Red Sea in the south and Mediterranean in the north. It crosses many lakes, which in its turn represent different habitats. 28 plankton ciliate taxa and species were collected from the canal waters during the present study. Much interest was focused on determining from which end of the canal these organisms were invading the opposite sea. Planktonic ciliates appear to enter the Suez Canal from the south via water currents; to do so it needs to be carried over a distance of 25 km along the canal from the Gulf of Suez into the Bitter Lakes, then pass across the Bitter Lakes before being carried a further 15 km along the canal into Lake Timsah. Plankton ciliate affinities and differences between the eastern Mediterranean and the Red Sea were discussed in the light of the results of distribution studies of the twenty eight species of plankton carried out. These observations point to the role of the canal as a selective barrier and/or as a link in the process of marine bio-invasions of planktonic organisms, while cases of invasion from one sea to the other are more likely to occur in either direction, those concerning species of indo-Pacific origin are more successful and numerous (23species). Meanwhile, the Suez Canal acts as a local endemic habitat by itself (5 species). Thus, the opening of the Suez Canal during the year of 1869 caused marine bio-invasions in the Mediterranean Sea and rarely in the Red Sea. Accordingly Red Sea species invaded the Mediterranean ecosystem and not vice versa. Finally, it would be concluded that, a continuous monitoring programme must be launched especially after the new expansion of the canal and opening the new one to record the recent invasive plankton species and follow up the distribution and abundance of those previously recorded as invasive or alien species to assess their impacts on the native biodiversity ofthe Suez Canal, Red Sea and Mediterranean.
