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detail the ultrastructure of Vitrella brassicaformis, concentrating on the apical region of the flagellar stage. A previous work described a lifestage, surrounded by roughly structured matter of the containing sporangium, with an intracytoplasmic axoneme structure suggested to develop into mature flagellum. Here we describe a novel stage with cells developing a flagellum extracellularly. These cells concurrently bud off the center of the sporangium, surrounded by smooth matter, in a process reminiscent of ectomerogony as seen in Eimeria. We suggest that the former process generates gamete-like flagellate progeny, while the latter process yields zooflagellates. We failed to find apical structure similar to the pseudoconoid in C. velia. We propose that the common ancestor of Apicomplexa and "chrompodellids" exhibited a complex lifecycle, while extant descendants underwent gradual reduction of these processes as forced by their environment. Acknowledgement: The authors would like to thank the Czech Science Foundation (JK, HJE, MO) and the Czech Academy of Sciences (ZF) for funding.
DIFFICULTIES IN ASSESSING THE GLOBAL DISTRIBUTION OF A MODEL ORGANISM - THE BIOGEOGRAPHY OF FAVELLA PANA-MENSIS (ALVEOLATA, CILIOPHORA) Ganser M., Agatha S.
University ofSalzburg, Dept. Ecology and Evolution [email protected] Accurate circumscriptions and determinations of species are essential for biodiversity and biogeo-graphy assessments; traditionally, the morpho-species concept was employed. Tintinnid ciliates are exceptional as - in contrast to the vast majority of ciliates - the whole taxonomy and classification of the more than one thousand marine planktonic species are almost exclusively based on characteristics of their vase-shaped loricae (houses). Because it is relatively easy to collect, preserve, examine, and classify, the lorica has allowed the accumulation of invaluable diversity and distribution data for more than two centuries. However, lorica-based taxonomy is problematic because of the high intraspecific variability and interspecific similarity of the loricae; so, the species limitations are currently unknown. Besides misidentifications, the diversity and geographic ranges perceived are especially affected by revisionary taxonomic treatises differing in their species circumscriptions from the original descriptions due to synonymisation (range of morphologic features became wider) and splitting (range of features became smaller) of species. Despite these difficulties, Montagnes (2013)
suggested the tintinnid genus Favella as a model for planktonic ciliates. In the present study on the biogeography of Favella panamensis, the species records from about one hundred of taxonomical and ecological studies were classified according to their quality: (i) reliable records from the type and neo-type localities mentioned in the original description and authoritative redescription; (ii) more or less reliable records supported by descriptions, measurements, and/or illustrations that fit the original description and redescription; and (iii) unsubstantiated records (mostly simple species lists) based on uncertain identifications. The comparison of the data provided by substantiated records with the original description revealed false positive and negative identifications. Since currently the species circumscriptions are uncertain, the usage of the original descriptions or authoritative redescriptions for the identification of tintinnid ciliates is strongly recommended. Only later, when the cell features and barcodes of the morphotypes are known, we might be able to perform justified synonymisations. References. Montagnes (2013): Ecophysiology and behavior of tintinnids. In: Dolan J.R., Montagnes D.J.S., Agatha S., Coats W.D. & Stoecker D.K. (2013): The Biology and Ecology of Tintinnid Ciliates: Models for Marine Plankton. Wiley-Blackwell: 85-121.
THE BEGINNING: INFERENCE OF THE TINTINNID ANCESTOR'S MORPHOLOGY (ALVEOLATA, SPIROTRICHA, TINTINNINA) Ganser M., Agatha S.
University ofSalzburg, Dept. Ecology and Evolution [email protected] Tintinnids are a speciose group of ciliates, whose taxonomy and systematics are almost exclusively based on lorica features. Physico-chemical factors and the cell cycle, however, influence these taxonomic characters, resulting in an artificial classification with several non-monophyletic groupings. The sparse cytological data and the more comprehensive molecular phylogenies indicate that the tintinnids developed in the marine environment and entered freshwater several times independently. The tintinnidiid genera Tintinnidium and Membranicola are typical representatives of the limnetic plankton and are characterized by a simple somatic ciliary pattern and a strong synapomorphy, namely, the two de-novo-originating ventral organelles. The family is sister to the remaining, mainly marine species. As yet, only a single member of the genus Tintinnidium, T. mucicola, is known to occur in marine and brackish coastal waters, suggesting that it might provide clues pivotal to
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infer the morphology of the tintinnid ancestor's morphology. Especially, the ventral organelles of the Tintinnidiidae require a closer inspection owing to their uncommon de-novo-origin which contrasts the intrakinetal proliferation of basal bodies in the other somatic kineties of the Tintinnidiidae and the somatic ciliature in all other tintinnids. Accordingly, the morphology of lorica and cell of T. mucicola are described based on live observations and protargol-impregnated material and the cell division pattern is analysed with special emphasis on the development of the ventral organelles. The study indicates that all somatic ciliary rows of T. mucicola are exclusively dikinetidal and develop by intrakinetal proliferation of basal bodies and thus demonstrate the plesiomorphic character states already present in the dorsal rows of the euplotids and hypotrichs as well as in the girdle and ventral kineties of the Oligotrichida. The species has two obliquely orientated kineties resembling the ventral organelles in the other Tintinnidium species and the monotypic genus Membranicola. Hence, the ancestor of the tintinnids apparently had exclusively dikinetidal somatic kineties all reproducing by intrakinetal proliferation of basal bodies, and the de-novo-origin of the ventral organelles in the remaining Tintinnidiidae necessitates confirmation. The study was financially supported by the Austrian Science Fund (FWF): Project P28790.
THE BLACK SEA TINTINNIDS (SPIROTRI-CHEA, CHOREOTRICHIA, TINTINNIDA): CURRENT STATE OF BIODIVERSITY AND SPECIES COMPOSITION Gavrilova N.A.
Institute of Marine Biological Researches, Russian Academy ofScience, Plankton department, Laboratory ofmicroplankton [email protected]
According to literary and own data considering recent nomenclature revision there were 20 tintinnid choreotrich species in the Black Sea: Codonella lagenula, Helicostomella subulata, Tintinnopsis campanula, T. compressa, T. lobiancoi, T. rossolimi, T. baltica, T. karajacensis, T. cylindrica, T. tubulosa, T. beroidea, T. meunieri, T. urnula, T. minuta, Tintinnidium mucicola, Metacylis jorgensenii, M. mereschkovskii, Favella ehrenbergii, Stenosemella ventricosa and S. nivalis.
It should be noted that against the background of stable level of tintinnid diversity we observed the significant changes in the species composition ofthe group. Thus from 2001 to 2015 we registered 8 invasive species: Eutintinnus lususundae, E. tubulosus, E. apertus, Eutintinnus sp., Salpingella decurtata,
Tintinnopsis tocantinensis, Rhizodomus tagatzi and Amphorellopsis acuta replacing the indigenous species as Codonella lagenula, Helicostomella subulata, T. compressa, T. lobiancoi, T. rossolimi and Metacylis jorgensenii. However, the indigenous Tintinnopsis campanula, which was not observed during 10 years (since 1999) again, began to be present in the plankton from 2009 constantly. The finds of alien species are not rare, during certain seasons they reach high abundances. For example, such species as Eutintinnus lususundae and E. tubulosa are often dominating in the plankton community.
The reasons for mentioned changes are not known exactly. It is possible that these related with invasion of ctenophore Mnemiopsis leidyi into the Black Sea, which caused significant changes in the plankton community structure. Resulting the current list of the Black Sea Tintinnida consist of 23 species including invasive.
MITOCHONDRIAL TRANSCRIPTOME OF LEPTOMONAS PYRRHOCORIS H10 - CLOSE MONOXENOUS RELATIVE OF LEISHMANIA CLADE
Gerasimov E.S.1, Flegontov P.N.2, Gasparyan A.V.1, Logacheva M.D.3, Kolesnikov A.A.1
1 - DepartmentofBiology, M.V. LomonosovMoscow State University, 119991, Moscow, Russia
2 - Biology Centre, Institute of Parasitology, Czech Academy of Sciences, 370 05 Ceske Budejovice (Budweis), Czech Republic
3 - Beloz.ersky Institute of Physico-ChemicalBiology, M.V. Lomonosov Moscow State University, 119991, Moscow, Russia
Mitochondrial genome of trypanosomatids have several unusual traits both in it's structural organization and in it's expression. About 22 mitochondrial genes are compactly grouped in coding region of maxicircle - major coding component of the mt-genome. Some transcripts undergo extensive RNA-editing process before they become mature mRNAs and this is mediated by small gRNAs coded in minicircles. Biological advantages of such complex expression system remains unclear but it definitely plays crucial role in mitochondrial genome expression. Editing is well-studied in some dixenous species like Trypanosoma brucei and Leishmania tarentolae but less data exists for monoxenous species. In this work we present a full mitochondrial transcriptome map of Leptomonas pyrrhocoris H10 generated using RNAseq data. The overall transcription profile appeared to be similar to profile of Leishmania tarentolae.
