title: Amphidoma languida sp. nov. (Dinophyceae) reveals a close relationship between Amphidoma and Azadinium.
abstract: Toxic algae such as Alexandrium and Azadinium have an important ecological impact and have originated several times independently within the dinophytes. Their closest relatives, however, are mostly unknown at present. A new dinophyte species, Amphidoma languida sp. nov., was isolated from Bantry Bay (Ireland) during a period of elevated azaspiracid toxicity in mussels. The new species was described in detail, and its phylogenetic position was analysed, by using a combination of light and electron microscopy, chemical detection methods, and sequence comparison of concatenated ribosomal RNA sequence data. Morphological similarities, such as cingular and hypothecal plates, the number and arrangement of sulcal plates, and the characteristic apical pore complex with a small X-plate centrally invading the first apical plate, indicated a close relationship between Amphidoma and Azadinium. However, no known azaspiracid analogues were detected in A. languida by liquid chromatography coupled with tandem mass-spectrometry. In a molecular phylogeny, the Amphidomataceae including Amphidoma and Azadinium were an independent lineage among other monophyletic major groups of the dinophytes such as the Suessiales, Prorocentrales, Gonyaulacales, and Peridiniales. Thus, the taxonomic affiliation of Azadinium is clarified, and our data may prove helpful in the development of specific and reliable molecular detection methods of toxic Azadinium.
authors: Alfred Wegener Institute for Polar and Marine Research, Am Handelshafen 12, D-27570 Bremerhaven, Germany. urban.tillmann@awi.de
authors: Urban
authors: U
authors: Tillmann
authors: Rafael
authors: R
authors: Salas
authors: Marc
authors: M
authors: Gottschling
authors: Bernd
authors: B
authors: Krock
authors: Daniel
authors: D
authors: O'Driscoll
authors: Malte
authors: M
authors: Elbrächter
mesh_terms: D056893:Alveolata / Q000145:classification* / Q000166:cytology / Q000235:genetics / Q000302:isolation & purification; D002851:Chromatography, High Pressure Liquid; D016000:Cluster Analysis; D016054:DNA, Protozoan / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D020459:Genes, rRNA; D007494:Ireland; D008387:Marine Toxins / Q000032:analysis; D008853:Microscopy; D010802:Phylogeny; D016053:RNA, Protozoan / Q000235:genetics; D012335:RNA, Ribosomal / Q000235:genetics; D012623:Seawater / Q000469:parasitology; D017422:Sequence Analysis, DNA; D013141:Spiro Compounds / Q000032:analysis; D053719:Tandem Mass Spectrometry; D000095702:Polyether Toxins
chemical_list: D016054:DNA, Protozoan; D004275:DNA, Ribosomal; D008387:Marine Toxins; D016053:RNA, Protozoan; D012335:RNA, Ribosomal; D013141:Spiro Compounds; C065096:RNA, ribosomal, 26S; C406592:azaspiracid; D000095702:Polyether Toxins