title: PHYLOGENETIC POSITION OF ATTHEYA LONGICORNIS AND ATTHEYA SEPTENTRIONALIS (BACILLARIOPHYTA)(1).
abstract: The phylogenetic position of diatoms belonging to the genus Attheya is presently under debate. Species belonging to this genus have been placed in the subclasses Chaetocerotophycidae and Biddulphiophycidae, but published phylogenetic trees based on 18S rDNA, morphology, and sexual reproduction indicate that this group of diatoms may be a sister group of the pennates. To clarify the position of Attheya, we studied the morphology, 18S rDNA, 16S rDNA of the chloroplasts, the rbcL large subunit (LSU) sequences of the chloroplasts, and the sterol composition of three different strains of Attheya septentrionalis (Østrup) R. M. Crawford and one strain of Attheya longicornis R. M. Crawford et C. Gardner. These data were compared with data from more than 100 other diatom species, covering the whole phylogenetic tree, with special emphasis on species belonging to the genera that have been suggested to be related to the genus Attheya. All data suggest that the investigated Attheya species form a separate group of diatoms, and there is no indication that they belong to either the Chaetocerotophycidae or the Biddulphiophycidae. Despite applying these various approaches, we were unable to determine the exact phylogenetic position of the investigated Attheya species within the diatoms.
authors.affiliation: Department of Marine Organic Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, the NetherlandsBigelow Laboratory for Ocean Sciences, PO Box 475, West Boothbay Harbor, Maine 04575, USADepartment of Biological Oceanography, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, the NetherlandsDepartment of Marine Organic Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, the Netherlands.
authors.forename: Sebastiaan W
authors.initials: SW
authors.lastname: Rampen
authors.affiliation: Department of Marine Organic Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, the NetherlandsBigelow Laboratory for Ocean Sciences, PO Box 475, West Boothbay Harbor, Maine 04575, USADepartment of Biological Oceanography, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, the NetherlandsDepartment of Marine Organic Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, the Netherlands.
authors.forename: Stefan
authors.initials: S
authors.lastname: Schouten
authors.affiliation: Department of Marine Organic Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, the NetherlandsBigelow Laboratory for Ocean Sciences, PO Box 475, West Boothbay Harbor, Maine 04575, USADepartment of Biological Oceanography, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, the NetherlandsDepartment of Marine Organic Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, the Netherlands.
authors.forename: F
authors.initials: F
authors.lastname: Elda Panoto
authors.affiliation: Department of Marine Organic Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, the NetherlandsBigelow Laboratory for Ocean Sciences, PO Box 475, West Boothbay Harbor, Maine 04575, USADepartment of Biological Oceanography, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, the NetherlandsDepartment of Marine Organic Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, the Netherlands.
authors.forename: Maaike
authors.initials: M
authors.lastname: Brink
authors.affiliation: Department of Marine Organic Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, the NetherlandsBigelow Laboratory for Ocean Sciences, PO Box 475, West Boothbay Harbor, Maine 04575, USADepartment of Biological Oceanography, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, the NetherlandsDepartment of Marine Organic Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, the Netherlands.
authors.forename: Robert A
authors.initials: RA
authors.lastname: Andersen
authors.affiliation: Department of Marine Organic Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, the NetherlandsBigelow Laboratory for Ocean Sciences, PO Box 475, West Boothbay Harbor, Maine 04575, USADepartment of Biological Oceanography, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, the NetherlandsDepartment of Marine Organic Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, the Netherlands.
authors.forename: Gerard
authors.initials: G
authors.lastname: Muyzer
authors.affiliation: Department of Marine Organic Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, the NetherlandsBigelow Laboratory for Ocean Sciences, PO Box 475, West Boothbay Harbor, Maine 04575, USADepartment of Biological Oceanography, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, the NetherlandsDepartment of Marine Organic Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, the Netherlands.
authors.forename: Ben
authors.initials: B
authors.lastname: Abbas
authors.affiliation: Department of Marine Organic Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, the NetherlandsBigelow Laboratory for Ocean Sciences, PO Box 475, West Boothbay Harbor, Maine 04575, USADepartment of Biological Oceanography, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, the NetherlandsDepartment of Marine Organic Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, the Netherlands.
authors.forename: Jaap S
authors.initials: JS
authors.lastname: Sinninghe Damsté
keywords: 16S rDNA; 18S rDNA; Attheya; Bacillariophyta; Biddulphiophycidae; Chaetocerotophycidae; morphology; rbcL; sterols