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Ruth Nielsen - One of the best experts on this subject based on the ideXlab platform.
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Description of Ulvella elegans sp. nov. and U. islandica sp. nov. (Ulvellaceae, Ulvophyceae) from Iceland - a study based on morphology of species in culture and tufA gene sequences
European Journal of Phycology, 2014Co-Authors: Ruth Nielsen, Karl Gunnarsson, Niels Daugbjerg, Gitte PetersenAbstract:Two new Ulvella species, U. elegans R. Nielsen & K. Gunnarsson and U. islandica R. Nielsen & K. Gunnarsson are described. These microfilamentous marine green algae were found in the sublittoral zone in northern Iceland, epiphytic on Euthora cristata and associated with a calcareous polychaete tube, respectively. Unialgal cultures were established from field-collected material for morphological observations. In culture, Ulvella elegans was characterized by rosettes of monostromatic pseudoparenchyma consisting of radiating filaments with a margin of mutually free filaments. Each cell had one pyrenoid. Hairs were not observed. Ulvella islandica had a heterotrichous morphology, consisting of dense tufts of upright broad branches and much narrower, rhizoid-like branches. Acrochaete-type hairs occurred; these are hyaline non-septate merocytic extensions from a more or less bulbous base, which may be separated from the vegetative cell below. Most cells had one pyrenoid except for a few broad cells which had two ...
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revision of the genus Ulvella Ulvellaceae ulvophyceae based on morphology and tufa gene sequences of species in culture with acrochaete and pringsheimiella placed in synonymy
Phycologia, 2013Co-Authors: Ruth Nielsen, Gitte Petersen, Ole Seberg, Niels Daugbjerg, Charles J Okelly, Brian WysorAbstract:Nielsen R., Petersen G., Seberg O., Daugbjerg N., O'Kelly C.J. and Wysor B. 2013. Revision of the genus Ulvella (Ulvellaceae, Ulvophyceae) based on morphology and tufA gene sequences of species in culture, with Acrochaete and Pringsheimiella placed in synonymy. Phycologia 52: 37–56. DOI: 10.2216/11-067.1 Microfilamentous green algae in the Ulvellaceae are notoriously difficult to identify and classify. We revised Ulvella based on the morphology of 46 unialgal culture isolates, including several from type localities, and we were guided by a phylogenetic reconstruction based on chloroplast-encoded tufA gene sequences. Species previously referred to Acrochaete, including the type species A. repens, formed a clade that included Pringsheimiella scutata and Ulvella lens, the type species of their respective genera. These species were placed in a single genus, and Ulvella had priority. The circumscription of the genus was emended to include microscopic species with branched filaments that may or may not form mon...
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New records of benthic marine algae for Norway, with notes on some rare species from the Florø district, western Norway
Sarsia, 1999Co-Authors: Tor Eiliv Lein, Ruth Nielsen, Grethe Bruntse, Karl Gunnarsson, Ulf BåmstedtAbstract:Abstract An investigation of the algal vegetation in the Floro district was undertaken in 1997. Representative samples were selectively collected at exposed and sheltered sites in February and September. New to Norway were: Acrochaete heteroclada, A. inflata, Aglaothamnion cf. pseudobyssoides, and Ulvella setchellii. Ceramium botryocarpum, C. pallidum and C. siliquosum have not previously been recorded in Norway, but may have been reported under different synonyms. Epicladia philipsii, Gracilariopsis longissima, Pseudendoclonium dynamenae, and Syncoryne reinkei were recently separated from other species and old records of these may in part cover the new species. The study extends the known northern boundary of distribution along the Norwegian west coast for 20 species. Reproductive male plants of Rhodochorton purpureum were observed, probably for the first time in nature. A summary of all species known to occur in the district is given and includes 33 Nostocophyceae, 121 Bangiophyceae, 64 Fucophyceae, and...
Gitte Petersen - One of the best experts on this subject based on the ideXlab platform.
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Description of Ulvella elegans sp. nov. and U. islandica sp. nov. (Ulvellaceae, Ulvophyceae) from Iceland - a study based on morphology of species in culture and tufA gene sequences
European Journal of Phycology, 2014Co-Authors: Ruth Nielsen, Karl Gunnarsson, Niels Daugbjerg, Gitte PetersenAbstract:Two new Ulvella species, U. elegans R. Nielsen & K. Gunnarsson and U. islandica R. Nielsen & K. Gunnarsson are described. These microfilamentous marine green algae were found in the sublittoral zone in northern Iceland, epiphytic on Euthora cristata and associated with a calcareous polychaete tube, respectively. Unialgal cultures were established from field-collected material for morphological observations. In culture, Ulvella elegans was characterized by rosettes of monostromatic pseudoparenchyma consisting of radiating filaments with a margin of mutually free filaments. Each cell had one pyrenoid. Hairs were not observed. Ulvella islandica had a heterotrichous morphology, consisting of dense tufts of upright broad branches and much narrower, rhizoid-like branches. Acrochaete-type hairs occurred; these are hyaline non-septate merocytic extensions from a more or less bulbous base, which may be separated from the vegetative cell below. Most cells had one pyrenoid except for a few broad cells which had two ...
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revision of the genus Ulvella Ulvellaceae ulvophyceae based on morphology and tufa gene sequences of species in culture with acrochaete and pringsheimiella placed in synonymy
Phycologia, 2013Co-Authors: Ruth Nielsen, Gitte Petersen, Ole Seberg, Niels Daugbjerg, Charles J Okelly, Brian WysorAbstract:Nielsen R., Petersen G., Seberg O., Daugbjerg N., O'Kelly C.J. and Wysor B. 2013. Revision of the genus Ulvella (Ulvellaceae, Ulvophyceae) based on morphology and tufA gene sequences of species in culture, with Acrochaete and Pringsheimiella placed in synonymy. Phycologia 52: 37–56. DOI: 10.2216/11-067.1 Microfilamentous green algae in the Ulvellaceae are notoriously difficult to identify and classify. We revised Ulvella based on the morphology of 46 unialgal culture isolates, including several from type localities, and we were guided by a phylogenetic reconstruction based on chloroplast-encoded tufA gene sequences. Species previously referred to Acrochaete, including the type species A. repens, formed a clade that included Pringsheimiella scutata and Ulvella lens, the type species of their respective genera. These species were placed in a single genus, and Ulvella had priority. The circumscription of the genus was emended to include microscopic species with branched filaments that may or may not form mon...
Aijaz Ahmad John - One of the best experts on this subject based on the ideXlab platform.
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Brown barcoded as red but reality is green! How epiphytic green algae confuse phycologists?
Webbia, 2015Co-Authors: Felix Bast, Satej Bhushan, Aijaz Ahmad JohnAbstract:Promises and perils of DNA barcoding are now well-known, but no studies have revealed the extent of taxonomic misidentification of algal specimens available in primary DNA sequence repositories. Our original objective was to assess the molecular identity of the ubiquitous brown alga Turbinaria ornata (Sargassaceae:, Fucales) from the southeast Indian coast. We extracted total genomic DNA from freshly collected algal thalli and sequenced the nuclear ribosomal DNA Internal Transcribed Spacer-1 (nrDNA ITS1) barcode locus. Following a BLASTn DNA sequence similarity search, the identity of our alga was Laurencia thyrsifera, a Pacific red alga that has never been reported in India, which came as a big surprise. Further analyses of BLAST hits using a robust phylogenetic framework of Bayesian Inference led to the conclusion that our sequence belonged to an epiphytic Ulvellacean green algal genus Ulvella, which might have been extracted and amplified with our universal ITS primers. This is the first report for Ulv...
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DNA barcoding of a new record of epi-endophytic green algae Ulvella leptochaete (Ulvellaceae, Chlorophyta) in India
Journal of Biosciences, 2014Co-Authors: Felix Bast, Satej Bhushan, Aijaz Ahmad JohnAbstract:Epi-endophytic green algae comprise one of the most diverse and phylogenetically primitive groups of green algae and are considered to be ubiquitous in the world’s oceans; however, no reports of these algae exist from India. Here we report the serendipitous discovery of Ulvella growing on intertidal green algae Cladophora glomerata and benthic red algae Laurencia obtusa collected from India. DNA barcodes at nuclear ribosomal DNA Internal Transcriber Spacer (nrDNA ITS) 1 and 2 regions for Indian isolates from the west and east coasts have been generated for the first time. Based on morphology and DNA barcoding, isolates were identified as Ulvella leptochaete . Phylogenetic reconstruction of concatenated dataset using Maximum Likelihood method differentiated Indian isolates from other accessions of this alga available in Genbank, albeit with low bootstrap support. Monophyly of Ulvella leptochaete was obvious in both of our phylogenetic analyses. With this first report of epi-endophytic algae from Indian territorial waters, the dire need to catalogue its cryptic diversity is highlighted and avenues of future research are discussed.
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dna barcoding of a new record of epi endophytic green algae Ulvella leptochaete Ulvellaceae chlorophyta in india
Journal of Biosciences, 2014Co-Authors: Felix Bast, Satej Bhushan, Aijaz Ahmad JohnAbstract:Epi-endophytic green algae comprise one of the most diverse and phylogenetically primitive groups of green algae and are considered to be ubiquitous in the world’s oceans; however, no reports of these algae exist from India. Here we report the serendipitous discovery of Ulvella growing on intertidal green algae Cladophora glomerata and benthic red algae Laurencia obtusa collected from India. DNA barcodes at nuclear ribosomal DNA Internal Transcriber Spacer (nrDNA ITS) 1 and 2 regions for Indian isolates from the west and east coasts have been generated for the first time. Based on morphology and DNA barcoding, isolates were identified as Ulvella leptochaete. Phylogenetic reconstruction of concatenated dataset using Maximum Likelihood method differentiated Indian isolates from other accessions of this alga available in Genbank, albeit with low bootstrap support. Monophyly of Ulvella leptochaete was obvious in both of our phylogenetic analyses. With this first report of epi-endophytic algae from Indian territorial waters, the dire need to catalogue its cryptic diversity is highlighted and avenues of future research are discussed. [Bast F, Bhushan S and John AA 2014 DNA barcoding of a new record of epi-endophytic green algae Ulvella leptochaete (Ulvellaceae, Chlorophyta) in India. J. Biosci. 39 711–716] DOI 10.1007/s12038-014-9459-3
Guoxiang Liu - One of the best experts on this subject based on the ideXlab platform.
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Ulvella tongshanensis Ulvellaceae chlorophyta a new freshwater species from china and an emended morphological circumscription of the genus Ulvella
Fottea, 2015Co-Authors: Huan Zhu, Frederik Leliaert, Zhijuan Zhao, Shuang Xia, Guoxiang LiuAbstract:A new freshwater species of Ulvella, Ulvella tongshanensis H. ZHU et G. LIU, is described from material collected from rocks under small waterfalls in Hubei Province, China. This unusual species differs from other species in the genus by the macroscopic and upright parenchymatous thalli, and by the particular habitat (most Ulvella species occur in marine environments). Phylogenetic analyses of plastid encoded rbcL and tufA, and nuclear 18S rDNA sequences, pointed towards the generic placement of Ulvella tongshanensis and also showed a close relationship with two other freshwater species, Ulvella bullata (Jao) H. ZHU et G. LIU, comb. nov. and Ulvella prasina (Jao) H. ZHU et G. LIU, comb. nov. The latter two were previously placed in the genus Jaoa and are characterized by disc-shaped to vesicular morphology. Our study once again shows that traditionally used morphological characters are poor indicators for phylogenetic relatedness in morphologically simple algae like the Ulvellaceae. Thus, the morphological circumscription of the genus Ulvella is here expanded to include: (1) thalli that are uniseriate in basal and apical parts, and parenchymatous in the middle portion with distinct differentiation of an unbranched dorsal side and a ventral side developing many short branches, and (2) epibiotic or epilithic, disc-shaped to vesicular thalli with a di- or tristromatic structure.
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Ulvella tongshanensis (Ulvellaceae, Chlorophyta), a new freshwater species from China, and an emended morphological circumscription of the genus Ulvella
Fottea, 2015Co-Authors: Huan Zhu, Frederik Leliaert, Zhijuan Zhao, Shuang Xia, Guoxiang LiuAbstract:A new freshwater species of Ulvella, U. tongshanensis H. Zhu et G. Liu, is described from material collected from rocks under small waterfalls in Hubei Province, China. This unusual species differs from other species in the genus by the macroscopic and upright parenchymatous thalli, and by the particular habitat (most Ulvella species occur in marine environments). Phylogenetic analyses of plastid encoded rbcL and tufA, and nuclear 18S rDNA sequences, pointed towards the generic placement of U. tongshanensis and also showed a close relationship with two other freshwater species, Ulvella bullata (Jao) H. Zhu et G. Liu, comb. nov. and Ulvella prasina (Jao) H. Zhu et G. Liu, comb. nov. The latter two were previously placed in the genus Jaoa and are characterized by disc–shaped to vesicular morphology. Our study once again shows that traditionally used morphological characters are poor indicators for phylogenetic relatedness in morphologically simple algae like the Ulvellaceae. Thus, the morphological circumscription of the genus Ulvella is here expanded to include: (1) thalli that are uniseriate in basal and apical parts, and parenchymatous in the middle portion with distinct differentiation of an unbranched dorsal side and a ventral side developing many short branches, and (2) epibiotic or epilithic, disc–shaped to vesicular thalli with a di– or tristromatic structure
Brian Wysor - One of the best experts on this subject based on the ideXlab platform.
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revision of the genus Ulvella Ulvellaceae ulvophyceae based on morphology and tufa gene sequences of species in culture with acrochaete and pringsheimiella placed in synonymy
Phycologia, 2013Co-Authors: Ruth Nielsen, Gitte Petersen, Ole Seberg, Niels Daugbjerg, Charles J Okelly, Brian WysorAbstract:Nielsen R., Petersen G., Seberg O., Daugbjerg N., O'Kelly C.J. and Wysor B. 2013. Revision of the genus Ulvella (Ulvellaceae, Ulvophyceae) based on morphology and tufA gene sequences of species in culture, with Acrochaete and Pringsheimiella placed in synonymy. Phycologia 52: 37–56. DOI: 10.2216/11-067.1 Microfilamentous green algae in the Ulvellaceae are notoriously difficult to identify and classify. We revised Ulvella based on the morphology of 46 unialgal culture isolates, including several from type localities, and we were guided by a phylogenetic reconstruction based on chloroplast-encoded tufA gene sequences. Species previously referred to Acrochaete, including the type species A. repens, formed a clade that included Pringsheimiella scutata and Ulvella lens, the type species of their respective genera. These species were placed in a single genus, and Ulvella had priority. The circumscription of the genus was emended to include microscopic species with branched filaments that may or may not form mon...