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Marc Gottschling - One of the best experts on this subject based on the ideXlab platform.

  • zero intercalary plates in parvodinium peridiniopsidaceae Peridiniales and phylogenetics of p elpatiewskyi comb nov
    Protist, 2020
    Co-Authors: Juliane Kretschmann, Anže žerdoner Calasan, Barbara E Meyer, Marc Gottschling
    Abstract:

    Parvodinium elpatiewskyi, comb. nov., is a common freshwater dinophyte without intercalary plates and with various spines on hypothecal sutures. However, the taxonomy of the species has had a complex history, and its systematic placement remained unclear. The conserved type of P. elpatiewskyi, comb. nov., illustrated here for the first time using electron microscopy, is an environmental sample. Based on the newly collected material from Berlin (Germany) we provide a morphological description using light and electron microscopy as well as new molecular rRNA sequence data to specify the phylogenetic position of P. elpatiewskyi, comb. nov. This species belongs to Peridiniopsidaceae, more precisely to Parvodinium, which usually possesses two intercalary plates. However, evolutionary inference indicates the loss of such plates in P. elpatiewskyi, comb. nov. Other traits that are of taxonomic importance and have not received enough attention in the past are the large Sd plate converging the second antapical plate and the presence of cellular hypocystal opening during replication.

  • Typification for reliable application of subspecific names within Peridinium cinctum (Peridiniales, Dinophyceae)
    Phytotaxa, 2019
    Co-Authors: Corinna Romeikat, Juliane Kretschmann, Alejandro Izquierdo López, Christine Tietze, Marc Gottschling
    Abstract:

    The application of scientific names is determined by means of nomenclatural types, and every name has to be typified properly. The concept has limitations for unicellular organisms, because original material frequently consists of drawings and/or inadequately preserved physical material. Peridinium cinctum is an abundant freshwater microalga and variable in both morphology and genotype. Morphological variation is mainly expressed in its epithecal conformation: shape deviations of plates, plate rearrangements, plate fusion and plate additions. Different epithecal conformations were traditionally described as either varieties of P. cinctum or were established as closely related species. Despite this, relations between varieties, ribotypes and geographic locations were oversighted, and the full spectrum of plate variation in P. cinctum is still not well represented. For this reason, we sampled localities in Germany and Poland, from which varieties of P. cinctum were described a century ago. We cultivated monoclonal strains, exhibiting two distinct ITS ribotypes, and assessed their epithecal variation of morphology. Based on ca 2,500 observations of individual cells we report a plethora of both plate and suture deviations from the archetypical epithecal conformation of P. cinctum. Morphologies corresponding to previously described varieties were rare, even at their type localities. Nevertheless, we found morphologies consistent with protologues in four cases and use this material for epitypification. These varieties are now linked to specific DNA sequences, allowing reliable application of scientific names for future studies.

  • They are young, and they are many: dating freshwater lineages in unicellular dinophytes
    Environmental Microbiology, 2019
    Co-Authors: Anže Žerdoner Čalasan, Juliane Kretschmann, Marc Gottschling
    Abstract:

    Dinophytes are one of few protist groups that have an extensive fossil record and are therefore appropriate for time estimations. However, insufficient sequence data and strong rate heterogeneity have been hindering to put dinophyte evolution into a time frame until now. Marine‐to‐freshwater transitions within this group are considered geologically old and evolutionarily exceptional due to strong physiological constraints that prevent such processes. Phylogenies based on concatenated rRNA sequences (including 19 new GenBank entries) of two major dinophyte lineages, Gymnodiniaceae and Peridiniales, were carried out using an uncorrelated molecular clock and five calibration points based on fossils. Contrarily to previous assumptions, marine‐to‐freshwater transitions are more frequent in dinophytes (i.e. five marine‐freshwater transitions in Gymnodiniaceae, up to ten but seven strongly supported transitions in Peridiniales), and none of them occurred as early as 140 MYA. Furthermore, most marine‐to‐freshwater transitions, and the followed diversification, took place after the Cretaceous–Paleogene boundary. Not older than 40 MYA, the youngest transitions within Gymnodiniaceae and Peridiniales occurred under the influence of the Eocene climate shift. Our evolutionary scenario indicates a gradual diversification of dinophytes without noticeable impact of catastrophic events, and their freshwater lineages have originated several times independently at different points in time.

  • Towards global distribution maps of unicellular organisms such as calcareous dinophytes based on DNA sequence information
    Marine Biodiversity, 2019
    Co-Authors: Anže Žerdoner Čalasan, Juliane Kretschmann, Natalia H. Filipowicz, Ramona-elena Irimia, Monika Kirsch, Marc Gottschling
    Abstract:

    Despite recent fruitful attempts to elucidate microbial biogeography in more detail, knowledge of distribution still lags behind for dinophytes. Evolutionary phenomena, such as cryptic speciation and modification due to the environment, hamper reliable conclusions about the distribution of this important plankton group. We combined newly collected samples from the Black Sea (ten new strains from three localities) with occurrence data, which have been gathered extensively over the past decade, in order to provide the first global distribution maps of four specific ribotypes assigned to the Scrippsiella lineage (Thoracosphaeraceae, Peridiniales) collected at a total of 39 sites. They showed a wide, partly overlapping distribution and shared the presence primarily at the coastal localities. Differences in abundance of specific ribotypes were observed, but the ribotype corresponding to the globally most frequently encountered species Scrippsiella acuminata has not yet been found in the Black Sea. We discuss the significance of DNA-based records for distribution maps particularly of unicellular organisms such as dinophytes. Based on a collective approach as exemplified in our study, we may start to understand in detail the ecological basis and the dynamics of the individual colonisation/invasion events, species establishment and consequent distribution in the microbiome, all of which have been changing drastically due to the ongoing climate change.

  • To be or not to be: On the usefulness of infraspecific names in Heterocapsa steinii (Heterocapsaceae, Peridiniales)
    Phytotaxa, 2019
    Co-Authors: Marc Gottschling, Malte Elbrächter, Urban Tillmann, Wolfhenning Kusber, Mona Hoppenrath
    Abstract:

    N/A

Mona Hoppenrath - One of the best experts on this subject based on the ideXlab platform.

Haifeng Gu - One of the best experts on this subject based on the ideXlab platform.

  • taxonomic revision phylogeny and cyst wall composition of the dinoflagellate cyst genus votadinium reid dinophyceae Peridiniales protoperidiniaceae
    Palynology, 2020
    Co-Authors: Pieter Gurdebeke, Kenneth Neil Mertens, Vera Pospelova, Haifeng Gu, Kazumi Matsuoka, Zhen Li, Kristin E Gribble, Kara Bogus, Henk Vrielinck
    Abstract:

    The taxonomy of the dinoflagellate cyst-based genus Votadinium has been in need of revision. This is accomplished here by integrating morphology, large subunit (LSU) rDNA sequences, and cyst wall c...

  • a review of rare poorly known and morphologically problematic extant marine organic walled dinoflagellate cyst taxa of the orders gymnodiniales and Peridiniales from the northern hemisphere
    Marine Micropaleontology, 2019
    Co-Authors: Kenneth Neil Mertens, Vera Pospelova, Haifeng Gu, Pieter Gurdebeke, Yoshihito Takano, Dave Clarke, Hilal Aydin, Zhen Li, Hyeon Ho Shin
    Abstract:

    Abstract Dinoflagellates are a major component of the modern plankton. Of the 2192 species of marine free-living dinoflagellates presently described, an increasing number are being shown to produce resting cysts (probably hypnozygotes) within their life cycle. With rare exception, only the resting cysts fossilize, so they are of central importance in tracing the history of dinoflagellates through geological time. Cysts of many of the more common dinoflagellate species have distinctive morphologies allowing their geographic and stratigraphic occurrences to be traced. An ever-increasing number of taxa are also being shown to produce distinctive and geologically preservable cysts, potentially enhancing our knowledge of the diverse representation of dinoflagellates through time. Here the organic-walled cysts of 73 rare, poorly known or morphologically problematic marine dinoflagellate cyst species belonging to the orders Gymnodiniales (nine species) and Peridiniales (64 species) are reviewed, described and illustrated, and their stratigraphic ranges assessed. The names Echinidinium aculeatum and Echinidinium transparantum are validated.

  • morphology ultrastructure and molecular phylogeny of cyst producing caladoa arcachonensis gen et sp nov Peridiniales dinophyceae from france and indonesia
    European Journal of Phycology, 2019
    Co-Authors: Kenneth Neil Mertens, Elizabeth Nezan, Li Gu, Vera Pospelova, Hikmah Thoha, Haifeng Gu
    Abstract:

    ABSTRACTThe dinoflagellate order Peridiniales encompasses several well circumscribed families. However, the family level of some genera, such as Bysmatrum and Vulcanodinium, has remained elusive fo...

  • two new generic names for dinophytes harbouring a diatom as an endosymbiont blixaea and unruhdinium kryptoperidiniaceae Peridiniales
    Phytotaxa, 2017
    Co-Authors: Marc Gottschling, Juliane Kretschmann, Anže žerdoner Calasan, Haifeng Gu
    Abstract:

    Kryptoperidiniaceae are a small group of dinophytes hosting a tertiary endosymbiont derived from a diatom (Tomas et al. 1973, Horiguchi & Pienaar 1994). Those so called ‘dinotoms’ (Imanian et al. 2011) include Dinothrix , Durinskia , Galeidinium , Kryptoperidinium (= Phyllodinium ) and some species currently assigned to “ Peridiniopsis ” and “ Peridinium ” (Tamura et al. 2005, Horiguchi & Takano 2006, Hansen et al. 2007, Zhang et al. 2011). Besides ‘possessing a diatom endosymbiont’ as a highly derived trait, the monophyly of Kryptoperidiniaceae is also supported by a unique type of eyespot that has possibly derived from the original chloroplast (Moestrup & Daugbjerg 2007). In molecular trees, Kryptoperidiniaceae constitute a well supported monophyletic group (Kretschmann et al. unpubl.), but it is not finally resolved at present, whether they are embedded in the Thoracosphaeraceae or constitute their sister group (Gottschling & McLean 2013). Regarding habitat preference, molecular trees further indicate at least two independent marine→freshwater transitions in the Kryptoperidiniaceae during the late Paleogene at the latest (Žerdoner Calasan et al. unpubl.).

  • cyst theca relationship and phylogenetic positions of scrippsiella plana sp nov and s spinifera Peridiniales dinophyceae
    European Journal of Phycology, 2016
    Co-Authors: Kenneth Neil Mertens, Kazumi Matsuoka, Yoshihito Takano, Hilal Aydin, Siamak Bagheri, Francine M G Mccarthy, Haifeng Gu
    Abstract:

    AbstractSpecies belonging to the dinophyte genus Scrippsiella are frequently reported in marine waters, but information on their distribution in brackish environments is limited. Here we describe a new species, S. plana, through incubation of non-calcified cysts from sediments collected in the South China Sea and Caspian Sea. The vegetative cells consist of a conical epitheca and a rounded hypotheca with the plate formula of Po, X, 4′, 3a, 7′′, 5C+t, 5S, 5′′′, 2′′′′. It differs from other Scrippsiella species by its flattened body in dorsoventral view and a small first anterior intercalary (1a) plate (half the size of plate 3a). Scrippsiella plana strains from the South China Sea and Caspian Sea share identical internal transcribed spacer (ITS) sequences, and show phenotypic plasticity and local adaptation in growth rate at various salinities, consistent with the environments in which they originated. In addition, two strains of S. spinifera were obtained by incubating ellipsoid cysts with calcareous spin...

Kazumi Matsuoka - One of the best experts on this subject based on the ideXlab platform.

  • taxonomic revision phylogeny and cyst wall composition of the dinoflagellate cyst genus votadinium reid dinophyceae Peridiniales protoperidiniaceae
    Palynology, 2020
    Co-Authors: Pieter Gurdebeke, Kenneth Neil Mertens, Vera Pospelova, Haifeng Gu, Kazumi Matsuoka, Zhen Li, Kristin E Gribble, Kara Bogus, Henk Vrielinck
    Abstract:

    The taxonomy of the dinoflagellate cyst-based genus Votadinium has been in need of revision. This is accomplished here by integrating morphology, large subunit (LSU) rDNA sequences, and cyst wall c...

  • cyst theca relationship and phylogenetic positions of scrippsiella plana sp nov and s spinifera Peridiniales dinophyceae
    European Journal of Phycology, 2016
    Co-Authors: Kenneth Neil Mertens, Kazumi Matsuoka, Yoshihito Takano, Hilal Aydin, Siamak Bagheri, Francine M G Mccarthy, Haifeng Gu
    Abstract:

    AbstractSpecies belonging to the dinophyte genus Scrippsiella are frequently reported in marine waters, but information on their distribution in brackish environments is limited. Here we describe a new species, S. plana, through incubation of non-calcified cysts from sediments collected in the South China Sea and Caspian Sea. The vegetative cells consist of a conical epitheca and a rounded hypotheca with the plate formula of Po, X, 4′, 3a, 7′′, 5C+t, 5S, 5′′′, 2′′′′. It differs from other Scrippsiella species by its flattened body in dorsoventral view and a small first anterior intercalary (1a) plate (half the size of plate 3a). Scrippsiella plana strains from the South China Sea and Caspian Sea share identical internal transcribed spacer (ITS) sequences, and show phenotypic plasticity and local adaptation in growth rate at various salinities, consistent with the environments in which they originated. In addition, two strains of S. spinifera were obtained by incubating ellipsoid cysts with calcareous spin...

  • two new species formally attributed to protoperidinium oblongum aurivillius park et dodge Peridiniales dinophyceae evidence from cyst incubation experiments
    Review of Palaeobotany and Palynology, 2013
    Co-Authors: Chihiro Sarai, Hisae Kawami, Aika Yamaguchi, Kazumi Matsuoka
    Abstract:

    Cyst–theca relationships of the common armored dinoflagellate Protoperidinium oblongum were re-investigated by incubation experiments and molecular phylogenetic analysis. Living cysts provided for incubation experiments were collected from several places in Japan, including Omura Bay, West Japan and Lake Saroma in Hokkaido, North Japan. One hundred and four cysts were incubated and 18 motile cells were germinated from these cysts. To clarify their morphological characteristics both cysts and germinated thecate cells were observed, especially the archeopyle type, the number and shape of anterior intercalary plates, and the shape and development of apical and antapical horns. In order to provide molecular phylogenetic analysis, germinated cells from incubated cysts were examined for their LSU rDNA sequences. Results reveal that three morphologically different cysts produced three morphologically different thecate cells, which were previously known as Protoperidinium oblongum var. latidorsale, Protoperidinium oblongum var. inaequale, and Protoperidinium oblongum var. symmetricum. The molecular phylogenetic analysis demonstrated that the Oceania group in the genus Protoperidinium includes these three varieties as well as Protoperidinium divergens, Protoperidinium claudicans, and Protoperidinium steigingerae. This group is separated from Protoperidinium sensu stricto, and the three plankton forms are phylogenetically separate and independent species. Based on these facts, two new species, Protoperidinium quadrioblongum Sarai, Kawami et Matsuoka, the new name for Protoperidinium oblongum var. symmetricum and Protoperidinium paraoblongum Sarai, Kawami et Matsuoka for Protoperidinium oblongum var. inaequale are described.

  • cellular and body scale morphology of heterocapsa huensis sp nov Peridiniales dinophyceae found in hue vietnam
    Phycological Research, 2009
    Co-Authors: Mitsunori Iwataki, Hisae Kawami, Nguyen Van Nguyen, Yasuwo Fukuyo, Quang Doc Luong, Kazumi Matsuoka
    Abstract:

    SUMMARY Cellular and body scale structure of a new armored dinoflagellate Heterocapsa huensis, collected from Hue, Vietnam were investigated. Morphology of motile cell was observed by light, fluorescent and scanning electron microscopy, and body scale structure was examined by whole mounts of transmission electron microscopy. Cells of H. huensis were ellipsoid with a spherical nucleus located in the posterior and multiple pyrenoids located above the nucleus; this arrangement was similar to that of Heterocapsa pygmaea. Transmission electron microscopy revealed ultrastructure of the body scales consisted of a rounded triangular basal plate and three-dimensional ornaments. Structure of the basal plate resembles that of Heterocapsa illdefina; however, the number of the peripheral spine is different from that of H. illdefina and this structure has never been reported from Heterocapsa species. A new Heterocapsa species, H. huensis Iwataki et Matsuoka sp. nov., is described based on positions of organelles and body scale ultrastructure.

  • a new cyst theca relationship for protoperidinium parthenopes zingone montresor 1988 Peridiniales dinophyceae
    Palynology, 2009
    Co-Authors: Hisae Kawami, Kazumi Matsuoka
    Abstract:

    Abstract Organic-walled resting cysts of Protoperidinium parthenopes Zingone & Montresor 1988 were collected from a sediment trap in Omura Bay, western Japan. The cysts are spherical and pale brown in color. The cyst wall has two layers: a thick endophragm with granulate surface, and a thin periphragm. Three complete and incomplete parasutures appear on the surface of the endocyst. The archeopyle formed on the endocyst is basically saphopylic and compound with some combination of complete and incomplete parasutures. The cyst of Protoperidinium parthenopes closely resembles the cyst of Protoperidinium americanum (Gran & Braarud 1935) Balech 1974, but differs in the shape of the periphragm, the cyst diameter, and in the archeopyle.

Nicolas Chomerat - One of the best experts on this subject based on the ideXlab platform.

  • laciniporus arabicus gen et sp nov dinophyceae Peridiniales a new thecate marine sand dwelling dinoflagellate from the northern indian ocean arabian sea 1
    Journal of Phycology, 2019
    Co-Authors: Maria Saburova, Nicolas Chomerat
    Abstract:

    : A new thecate, photosynthetic, sand-dwelling marine dinoflagellate, Laciniporus arabicus gen. et sp. nov., is described from the subtidal sediments of the Omani coast in the Arabian Sea, northern Indian Ocean, based on detailed morphological and molecular data. Cells of L. arabicus are small (16.2-30.1 μm long and 13.1-23.2 μm wide), dorsoventrally compressed, with a small apical flap-shaped projection pointing to the left. The thecal plate pattern is distinguished by minute first precingular plate and sulcus, which extends into the epitheca, with large anterior and right sulcal plates. The Kofoidian thecal tabulation is Po, X, 4', 2a, 7'', 6c, 6s, 5''', 2''''. Morphologically, the revealed plate pattern has an affinity to the Peridiniales, and LSU rDNA based phylogenetic analyses placed L. arabicus within the Thoracosphaeraceae, close to calcareous-cyst producing scrippsielloids, predatory pfiesteriaceans, and photosynthetic freshwater peridinioids Chimonodinium lomnickii and Apocalathium spp. However, the thecal plate arrangement of L. arabicus differs noticeably from any currently described dinoflagellates, and the species stands out from closely related taxa by extensive differences in physiology and ecology.

  • taxonomic characterization of a brackish water bloom forming peridiniopsis species Peridiniales dinophyceae from iraq
    Marine Biodiversity Records, 2016
    Co-Authors: Hameed A Hameed, Maria Saburova, Nicolas Chomerat
    Abstract:

    The occurrence of a small brackish water bloom-forming dinoflagellate belonging to the genus Peridiniopsis is reported for the first time from the Shatt Al-Arab River in Iraq. Based on the study of cell morphology, this taxon was attributed to the recently described Peridiniopsis minima, recorded so far only from the Jiulongjiang River, China. The description of P. minima was extended to include some previously unreported details of the thecal surface, apical pore complex, and sulcus structure using light and scanning electron microscopy. Cells of this species from Iraq were oval to rhombic in shape and slightly dorso-ventrally compressed, with distinct red eyespot and endosymbiont nucleus. Cells were covered by a thin theca with the Kofoidian plate formula Po, X, 3′, 1a, 6″, 5c, 5 s, 5′′′, 2′′′′. Complementing the original description of the species, five plates were discerned in the composition of the sulcal area, and the presence of small median sulcal plate was confirmed. The finding of P. minima in the waters of Shatt Al-Arab River represents a new addition to the Iraqi aquatic microflora. Our observations of this dinoflagellate in brackish waters of the Shatt Al-Arab River system extend the known range of salinity tolerance for this species.

  • morphology and ssu rdna phylogeny of durinskia agilis kofoid swezy comb nov Peridiniales dinophyceae a thecate marine sand dwelling dinoflagellate formerly classified within gymnodinium
    Phycologia, 2012
    Co-Authors: Maria Saburova, Nicolas Chomerat, Mona Hoppenrath
    Abstract:

    Saburova M., Chomerat N. and Hoppenrath M. 2012. Morphology and SSU rDNA phylogeny of Durinskia agilis (Kofoid & Swezy) comb. nov. (Peridiniales, Dinophyceae), a thecate, marine, sand-dwelling dinoflagellate formerly classified within Gymnodinium. Phycologia 51: 287–302. DOI: 10.2216/10-22.1 A new taxon of the dinoflagellate genus Durinskia Carty & Cox, previously considered a member of Gymnodinium Stein, is characterized from intertidal sand flats of Kuwait, in the northwestern part of the Arabian (Persian) Gulf. The taxonomic status of this dinoflagellate was reassessed on the basis of morphological and molecular data. Light and electron microscopical examinations revealed a previously undescribed delicate theca. The thecal plate formula is Po, x, 4′, 2a, 7″, 5c, 6s, 5‴, 2‴′. Based on the cell shape, thecal plate arrangement, the presence of a slit-like apical pore and an eyespot, as well as on SSU rDNA sequence data, the organism is reclassified as Durinskia agilis (Kofoid & Swezy) Saburova, Chomerat &...

  • Morphology and SSU rDNA phylogeny of Durinskia agilis (Kofoid & Swezy) comb. nov. (Peridiniales, Dinophyceae), a thecate, marine, sand-dwelling dinoflagellate formerly classified within Gymnodinium
    Phycologia, 2012
    Co-Authors: Maria Saburova, Nicolas Chomerat, Mona Hoppenrath
    Abstract:

    Saburova M., Chomerat N. and Hoppenrath M. 2012. Morphology and SSU rDNA phylogeny of Durinskia agilis (Kofoid & Swezy) comb. nov. (Peridiniales, Dinophyceae), a thecate, marine, sand-dwelling dinoflagellate formerly classified within Gymnodinium. Phycologia 51: 287–302. DOI: 10.2216/10-22.1 A new taxon of the dinoflagellate genus Durinskia Carty & Cox, previously considered a member of Gymnodinium Stein, is characterized from intertidal sand flats of Kuwait, in the northwestern part of the Arabian (Persian) Gulf. The taxonomic status of this dinoflagellate was reassessed on the basis of morphological and molecular data. Light and electron microscopical examinations revealed a previously undescribed delicate theca. The thecal plate formula is Po, x, 4′, 2a, 7″, 5c, 6s, 5‴, 2‴′. Based on the cell shape, thecal plate arrangement, the presence of a slit-like apical pore and an eyespot, as well as on SSU rDNA sequence data, the organism is reclassified as Durinskia agilis (Kofoid & Swezy) Saburova, Chomerat &...

  • protoperidinium bolmonense sp nov Peridiniales dinophyceae a small dinoflagellate from a brackish hypereutrophic lagoon south of france
    Phycologia, 2008
    Co-Authors: Nicolas Chomerat, Alain Coute
    Abstract:

    Described is a new Protoperidinium species from a brackish and hypereutrophic lagoon in the South of France, the Bolmon lagoon (‘Etang de Bolmon’). Protoperidinium bolmonense sp. nov. is a small dinoflagellate with a plate formula of Po, X, 4′, 3a, 7″, 3c, 4(?)s, 5‴ and 2″″. Its peculiar features are the presence of only three cingular plates, the marked extension of the second intercalary plate (2a) which abuts the second precingular plate (2″), the marked dorsoventral flattening and the shape of characteristic plates. Different variations of the epithecal plate pattern were observed in P. bolmonense population, involving the division or the fusion of pre-existing plates. Only one other Protoperidinium species, P. vorax, is known to possess only three cingular plates, but the thecal plate arrangement is not exactly the same. The relationship with other congeneric species and the position within the genus are discussed. From an ecological point of view, P. bolmonense was present in spring, in an oligo-mesohaline range of the salinity, which is not usual for Protoperidinium species. Because of the hypereutrophic conditions pertaining in the lagoon, the phytoplankton was abundant with dominant Planktothrix agardhii (cyanoprokaryota) and other autotrophic species. So, the latter might represent an important source of food for some marine heterotrophic dinoflagellates, especially those that can tolerate brackish water. In such environments, where large amounts of phytoplankton species are mixed, the identification of small dinoflagellates can be tedious. Scanning electron microscopy is very useful, and a simple method is described to isolate, prepare and observe a few dinoflagellate cells.