1. A new diatom species P. hallegraeffii sp. nov. belonging to the toxic genus Pseudo-nitzschia (Bacillariophyceae) from the East Australian Current
- Author
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Shauna A. Murray, Martina A. Doblin, Penelope A. Ajani, Malwenn Lassudrie, and Arjun Verma
- Subjects
0106 biological sciences ,0301 basic medicine ,Species Delimitation ,Speciation ,lcsh:Medicine ,01 natural sciences ,Geographical Locations ,Database and Informatics Methods ,chemistry.chemical_compound ,Genotype ,Electron Microscopy ,lcsh:Science ,Clade ,Phylogeny ,Data Management ,Microscopy ,Multidisciplinary ,biology ,Phylogenetic tree ,Eukaryota ,Domoic acid ,Phylogenetic Analysis ,Plants ,Plankton ,Phylogenetics ,Sequence Analysis ,Research Article ,Computer and Information Sciences ,Multiple Alignment Calculation ,Evolutionary Processes ,Algae ,Bioinformatics ,General Science & Technology ,Sequence analysis ,Oceans and Seas ,Oceania ,Zoology ,Research and Analysis Methods ,03 medical and health sciences ,Computational Techniques ,Animals ,Evolutionary Systematics ,Taxonomy ,Toxins, Biological ,Diatoms ,Evolutionary Biology ,010604 marine biology & hydrobiology ,lcsh:R ,Organisms ,Australia ,Biology and Life Sciences ,Water ,Sequence Analysis, DNA ,Ribosomal RNA ,biology.organism_classification ,Invertebrates ,Split-Decomposition Method ,030104 developmental biology ,Diatom ,chemistry ,Phytoplankton ,People and Places ,lcsh:Q ,Transmission Electron Microscopy ,Sequence Alignment - Abstract
© 2018 Ajani et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. A new species belonging to the toxin producing diatom genus Pseudo-nitzschia, P. hallegraeffii sp. nov., is delineated and described from the East Australian Current (EAC). Clonal cultures were established by single cell isolation from phytoplankton net hauls collected as part of a research expedition in the EAC region in 2016 on the RV Investigator. Cultures were assessed for their morphological and genetic characteristics, their sexual compatibility with other Pseudo-nitzschia species, and their ability to produce domoic acid. Light and transmission electron microscopy revealed cells which differed from their closest relatives by their cell width, rows of poroids, girdle band structure and density of band straie. Phylogenetic analyses based on sequencing of nuclear-encoded ribosomal deoxyribonucleic acid (rDNA) regions showed this novel genotype clustered within the P. delicatissima complex, but formed a discrete clade from its closest relatives P. dolorosa, P. simulans, P. micropora and P. delicatissima. Complementary base changes (CBCs) were observed in the secondary structure of the 3’ nuclear ribosomal transcribed spacer sequence region (ITS2) between P. hallegraeffii sp. nov. and its closest related taxa, P. simulans and P. dolorosa. Under laboratory conditions, and in the absence of any zooplankton cues, strains of P. hallegraeffii sp. nov. did not produce domoic acid (DA) and were not sexually compatible with any other Pseudo-nitzschia clones tested. A total of 18 Pseudo-nitzschia species, including three confirmed toxigenic species (P. cuspidata, P. multistriata and P. australis) have now been unequivocally confirmed from eastern Australia.
- Published
- 2018