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Shigeki Mayama - One of the best experts on this subject based on the ideXlab platform.
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Navicula nielsfogedii j c taylor cocquyt sp nov a new diatom bacillariophyta from tropical and sub tropical africa
Fottea, 2016Co-Authors: Jonathan C Taylor, Christine Cocquyt, Shigeki MayamaAbstract:In this paper we describe Navicula nielsfogedii sp. nov., a commonly occurring diatom through central and southern Africa and distributed from the sub-tropical zones of South Africa to tropical central Africa. We have examined the material of the most closely related species described from Africa, Navicula feuerbornii f. africana Foged and suggest that this species may be conspecific with Navicula heimansioides Lange-Bertalot and to have no link to the taxon N. feuerbornii Hustedt sensu Simonsen. With reference to Navicula feuerbornii f. africana we also discuss the changes over time in diatom species concepts, what we have dubbed 'species concept drift', and the consequences this holds for accurately identifying diatom taxa. As the newly described species is widely distributed and common in some samples from tropical and subtropical Africa we conclude that it may be a useful additional indicator organism for water quality monitoring in the region.
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Navicula nielsfogedii J.C. Taylor & Cocquyt sp. nov., a new diatom (Bacillariophyta) from tropical and sub-tropical Africa
Fottea, 2016Co-Authors: Jonathan C Taylor, Christine Cocquyt, Shigeki MayamaAbstract:In this paper we describe Navicula nielsfogedii sp. nov., a commonly occurring diatom through central and southern Africa and distributed from the sub-tropical zones of South Africa to tropical central Africa. We have examined the material of the most closely related species described from Africa, Navicula feuerbornii f. africana Foged and suggest that this species may be conspecific with Navicula heimansioides Lange-Bertalot and to have no link to the taxon N. feuerbornii Hustedt sensu Simonsen. With reference to Navicula feuerbornii f. africana we also discuss the changes over time in diatom species concepts, what we have dubbed 'species concept drift', and the consequences this holds for accurately identifying diatom taxa. As the newly described species is widely distributed and common in some samples from tropical and subtropical Africa we conclude that it may be a useful additional indicator organism for water quality monitoring in the region.
Jonathan C Taylor - One of the best experts on this subject based on the ideXlab platform.
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Navicula nielsfogedii j c taylor cocquyt sp nov a new diatom bacillariophyta from tropical and sub tropical africa
Fottea, 2016Co-Authors: Jonathan C Taylor, Christine Cocquyt, Shigeki MayamaAbstract:In this paper we describe Navicula nielsfogedii sp. nov., a commonly occurring diatom through central and southern Africa and distributed from the sub-tropical zones of South Africa to tropical central Africa. We have examined the material of the most closely related species described from Africa, Navicula feuerbornii f. africana Foged and suggest that this species may be conspecific with Navicula heimansioides Lange-Bertalot and to have no link to the taxon N. feuerbornii Hustedt sensu Simonsen. With reference to Navicula feuerbornii f. africana we also discuss the changes over time in diatom species concepts, what we have dubbed 'species concept drift', and the consequences this holds for accurately identifying diatom taxa. As the newly described species is widely distributed and common in some samples from tropical and subtropical Africa we conclude that it may be a useful additional indicator organism for water quality monitoring in the region.
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Navicula nielsfogedii J.C. Taylor & Cocquyt sp. nov., a new diatom (Bacillariophyta) from tropical and sub-tropical Africa
Fottea, 2016Co-Authors: Jonathan C Taylor, Christine Cocquyt, Shigeki MayamaAbstract:In this paper we describe Navicula nielsfogedii sp. nov., a commonly occurring diatom through central and southern Africa and distributed from the sub-tropical zones of South Africa to tropical central Africa. We have examined the material of the most closely related species described from Africa, Navicula feuerbornii f. africana Foged and suggest that this species may be conspecific with Navicula heimansioides Lange-Bertalot and to have no link to the taxon N. feuerbornii Hustedt sensu Simonsen. With reference to Navicula feuerbornii f. africana we also discuss the changes over time in diatom species concepts, what we have dubbed 'species concept drift', and the consequences this holds for accurately identifying diatom taxa. As the newly described species is widely distributed and common in some samples from tropical and subtropical Africa we conclude that it may be a useful additional indicator organism for water quality monitoring in the region.
Christine Cocquyt - One of the best experts on this subject based on the ideXlab platform.
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Navicula nielsfogedii j c taylor cocquyt sp nov a new diatom bacillariophyta from tropical and sub tropical africa
Fottea, 2016Co-Authors: Jonathan C Taylor, Christine Cocquyt, Shigeki MayamaAbstract:In this paper we describe Navicula nielsfogedii sp. nov., a commonly occurring diatom through central and southern Africa and distributed from the sub-tropical zones of South Africa to tropical central Africa. We have examined the material of the most closely related species described from Africa, Navicula feuerbornii f. africana Foged and suggest that this species may be conspecific with Navicula heimansioides Lange-Bertalot and to have no link to the taxon N. feuerbornii Hustedt sensu Simonsen. With reference to Navicula feuerbornii f. africana we also discuss the changes over time in diatom species concepts, what we have dubbed 'species concept drift', and the consequences this holds for accurately identifying diatom taxa. As the newly described species is widely distributed and common in some samples from tropical and subtropical Africa we conclude that it may be a useful additional indicator organism for water quality monitoring in the region.
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Navicula nielsfogedii J.C. Taylor & Cocquyt sp. nov., a new diatom (Bacillariophyta) from tropical and sub-tropical Africa
Fottea, 2016Co-Authors: Jonathan C Taylor, Christine Cocquyt, Shigeki MayamaAbstract:In this paper we describe Navicula nielsfogedii sp. nov., a commonly occurring diatom through central and southern Africa and distributed from the sub-tropical zones of South Africa to tropical central Africa. We have examined the material of the most closely related species described from Africa, Navicula feuerbornii f. africana Foged and suggest that this species may be conspecific with Navicula heimansioides Lange-Bertalot and to have no link to the taxon N. feuerbornii Hustedt sensu Simonsen. With reference to Navicula feuerbornii f. africana we also discuss the changes over time in diatom species concepts, what we have dubbed 'species concept drift', and the consequences this holds for accurately identifying diatom taxa. As the newly described species is widely distributed and common in some samples from tropical and subtropical Africa we conclude that it may be a useful additional indicator organism for water quality monitoring in the region.
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observations on the diatom Navicula hedinii hustedt bacillariophyceae and its transfer to a new genus envekadea van de vijver et al gen nov
European Journal of Phycology, 2009Co-Authors: Marija Gligora, Friedel Hinz, Christine Cocquyt, Koraljka Kralj, Anđelka Plenkovicmoraj, Eva Acs, Istvan Grigorszky, Bart Van De VijverAbstract:The population of an unknown naviculoid diatom from Lake Vrana in Croatia was identified as Navicula hedinii, a species described in 1922 from a small lake in eastern Turkestan (China). This species has some similarities with Navicula pseudocrassirostris, a marine species found in European coastal waters. Based on the ultrastructure of the two species, they can no longer be included within the taxonomical concept of Navicula sensu stricto. Following a comparative morphological analysis of both species with genera bearing similar characters (Adlafia, Veigaludwigia, Kobayasiella, Cavinula, Stenoneis, Climaconeis, Berkeleya, Sellaphora, Cosmioneis), a new genus, Envekadea is proposed for the two species. The new genus is characterized by a sigmoid raphe course with golfclub-like terminal fissures deflected in opposite directions, the areolae covered by external porous hymenes and the presence of one chloroplast, H-shaped in valve view.
J. Nelson Navarro - One of the best experts on this subject based on the ideXlab platform.
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OBSERVATIONS OF A TUBE‐DWELLING DIATOM: Navicula HAMULIFERA (BACILLARIOPHYCEAE)1
Journal of Phycology, 2004Co-Authors: J. Nelson NavarroAbstract:Colonies of the tube-dwelling diatom Navicula hamulifera Grunow living on mangrove prop roots in Indian River, Florida and at La Parguera, Puerto Rico, were studied using light and electron microscopy. Observations of the tube morphology and cell structure of this diatom from fresh samples and cultures are described, as well as the ultrastructural morphology of its frustule. The formation of tubes by this diatom is reported for the first time. Comparisons are made with the closest species; Navicula delognei V.H. and Navicula pseudoco moides Hendey.
Bart Van De Vijver - One of the best experts on this subject based on the ideXlab platform.
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Two new Navicula species (Bacillariophyceae) from Western Europe
Phytotaxa, 2015Co-Authors: Aude Beauger, Olivier Voldoire, Adrienne Mertens, René Le Cohu, Bart Van De VijverAbstract:During a survey of some springs in the French Central Massif, a new Navicula species (Bacillariophyceae) was found: Navicula sanctamargaritae Beauger sp. nov. A second new Navicula species was observed during a routine biomonitoring project in Flanders: Navicula flandriae Van de Vijver & A.Mertens sp. nov.. The new species are formally described using light and scanning electron microscopy. Both species present a unique set of morphological characters including the structure of the central raphe endings, the striation pattern, the valve dimensions and outline, which allows their separation from similar Navicula taxa such as N . korzeniewskii , N . recens or N . cincta . The ecological preferences of each species are briefly discussed.
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morphology typification and critical analysis of some ecologically important small naviculoid species bacillariophyta
Fottea, 2015Co-Authors: Carlos E Wetzel, Bart Van De Vijver, Luc Ector, Pierre Compere, David G. MannAbstract:The identity and nomenclatural history of several small-celled naviculoid taxa are revisited. The species discussed here are important from the ecological point of view since they are often dominant in benthic freshwater communities. The original concepts of several species that have suffered major taxonomic drift due to their entangled nomenclatural history are discussed, and forgotten epithets are resurrected. We examined the original material of Navicula aggerica E. Reichardt, Navicula atomoides Grunow, N. crassulexigua E. Reichardt, N. minima Grunow, N. minima var. typica R. Ross, N. minutissima (Kutz.) Grunow, N. saugerresii Desm., N. seminulum Grunow, N. seminulum var. intermedia Hust., N. seminulum var. radiosa Hust., N. stroemii Hust., N. subbacillum Hust., N. subseminulum Hust., N. tantula Hust., N. vasta Hust., N. ventraloides Hust., Stauroneis fonticola Hust., and Synedra minutissima Kutz. Several of these names were regarded as synonyms in many floristic works and, as such, remained forgotten or ignored. Analyses using light and scanning electron microscopy indicate conspecificity of Navicula minima (= Sellaphora seminulum sensu auct. nonnull.) with Sellaphora saugerresii (Desm.) C.E. Wetzel et D.G. Mann comb. nov., which has priority against N. minima. Synedra minutissima is lectotypified and transferred to Halamphora minutissima (Kutz.) C.E. Wetzel et Compere comb. nov. Navicula minutissima (Kutz.) Grunow 1860, nom. illeg. and Navicula minima Grunow pro parte, typo excl. designate one and the same species (valid and legitimate), currently known as Sellaphora aggerica (E. Reichardt) Falasco et Ector. We consider Sellaphora atomoides (Grunow) C.E. Wetzel et Van de Vijver comb. nov. (= Eolimna tantula sensu auct. nonnull.) and Sellaphora nigri (De Not.) C.E. Wetzel et Ector comb. nov. (= Eolimna minima sensu auct. nonnull.) to be separate species, although morphologically very similar. Sellaphora crassulexigua (E. Reichardt) C.E. Wetzel et Ector comb. nov. and Sellaphora subseminulum (Hust.) C.E. Wetzel comb. nov. are rarely encountered, but usually found in calcareous springs and aerial habitats, respectively. All species are transferred to the genus Sellaphora on the basis of their valve morphology, pending molecular studies confirming the monophyly of the group once living material of each can be located and brought into clonal culture. Additionally, 64 established taxa from Navicula s.l., Eolimna or Naviculadicta are formally transferred to Sellaphora. Navicula subminuscula Manguin is formally transferred to the genus Craticula Grunow.
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Revision of Navicula striolata (Grunow) Lange-Bertalot and N. rumaniensis Hustedt with the description of N. friedelhinziae sp. nov.
Phytotaxa, 2015Co-Authors: Agata Z. Wojtal, Krisztina Buczkó, Nadja Ognjanova-rumenova, Janusz Siwek, Bart Van De VijverAbstract:Navicula striolata was originally described as N. digitoradiata var. striolata from modern material collected in Sweden . After examination of a sample collected from Belgium, the variety was transferred to N. reinhardtii as N. reinhardti var. gracilior. From this time a large mix up of these and related taxa was observed in the literature. A similar species, Navicula rumaniensis had also been established in 1934 from Neogene Romanian materials but there has been much confusion regarding the status of these taxa, leading to a poor understanding of their distribution. In this study, type material of Navicula digitoradiata var. striolata , N. reinhardtii var. gracilior and N. rumaniensis are revised using light and scanning electron microscopy in order to clarify their identity and to investigate possible conspecificity. The results indicate that these species are not synonyms. Conspecificity of the modern N. digitoradiata var. striolata and N. reinhardti var. gracilior was confirmed and lectotypes of both varieties have been designated whereas N. rumaniensis proved to be a separate species. In addition, the study of Neogene material from Bulgaria revealed the presence of a new Navicula taxon— N. friedelhinziae . The morphology of these and similar taxa is discussed.
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Revision of the genus Navicula s.s. (Bacillariophyceae) in inland waters of the Sub-Antarctic and Antarctic with the description of five new species
Phycologia, 2011Co-Authors: Bart Van De Vijver, Ralitsa Zidarova, Mieke Sterken, Elie Verleyen, Myriam De Haan, Wim Vyverman, Friedel Hinz, Koen SabbeAbstract:Abstract Van de Vijver B., Zidarova R., Sterken M., Verleyen E., de Haan M., Vyverman W., Hinz F. and Sabbe K. 2011. Revision of the genus Navicula s.s. (Bacillariophyceae) in inland waters of the Sub-Antarctic and Antarctic with the description of five new species. Phycologia 50: 281–297. DOI: 10.2216/10-49.1 A revision of the diatom genus Navicula s.s. in inland water samples from the Sub-Antarctic and Antarctic resulted in the description of five new species, viz. Navicula australoshetlandica Van de Vijver sp. nov., N. dobrinatemniskovae Zidarova & Van de Vijver sp. nov., N. cremeri Van de Vijver & Zidarova sp. nov., N. conveyi Van de Vijver sp. nov. and Navicula bicephaloides Van de Vijver & Zidarova sp. nov. The new species are extensively compared with other similar species. The morphology and taxonomy of three other Navicula taxa present in the same materials are briefly discussed. A critical revision of literature reports of Navicula taxa in the Antarctic and Sub-Antarctic region indicates that de...
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Four new Navicula (Bacillariophyta) species from Swedish rivers
Cryptogamie Algologie, 2010Co-Authors: Bart Van De Vijver, Amelie Jarlman, Horst Lange-bertalotAbstract:Durant une analyse des diatomees lotiques des rivieres en Suede, plusieurs nouvelles especes de Navicula (Bacillariophyceae) ont ete trouvees: Navicula anionioides sp. nov., N. ireneae sp. nov., N. scaniae sp. nov. et N. ceciliae sp. nov. Les nouvelles especes sont decrites a partir d'observations en microscopie optique et a balayage. Chaque nouvelle espece presente une combinaison unique de caracteres morphologiques comme la structure des terminaisons centrales du raphe, la striation, les dimensions des valves et la forme generale des valves qui permet de les separer d'autres especes semblables du genre Navicula comme N. cryptocephala, N. radiosafallax ou N. antonii. Les preferences ecologiques de chaque espece sont brievement discutees. Enfin, la distribution des Navicula s.s. dans les eaux continentales d'Europe est brievement discutee.
