Taxonomy of Pfiesteria (Dinophyceae)

UNCG Author/Contributor (non-UNCG co-authors, if there are any, appear on document)
Vincent C. Henrich, Professor (Creator)
David L. Remington, Associate Professor (Creator)
Parke A. Rublee, Professor (Creator)
The University of North Carolina at Greensboro (UNCG )
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Abstract: The dinoflagellate species originally described as Pfiesteria shumwayae Glasgow et Burkholder, recently transferred to a new genus, Pseudopfiesteria Litaker et al., is reclassified into the redefined genus Pfiesteria Steidinger et Burkholder, as Pfiesteria shumwayae within the order Peridiniales. This change is based upon consideration of a compilation of previous and new morphological analyses and molecular phylogenetic analyses. Morphological analysis with scanning and transmission electron microscopy supports previous findings except in the sulcal area. In the cells examined, the sulcus is partly concealed by the peduncle cover plate (p.c.), which originates at the right side of the sulcus along the left side of the 6c and 5? plates. The fine structure of the p.c. appears similar to that of other thecal plates. The 1? plate can also extend slightly over the sulcus. Transmission electron microscopy revealed that Pfiesteria shumwayae can have at least six sulcal plates; the number remains uncertain and may vary. The sulcal plates of this small, delicately thecate species have not been clearly discerned by scanning electron microscopy of membrane-stripped and/or suture-swollen cells. The Kofoidian thecal plate formula for the genus Pfiesteria is Po, cp, X, 4', la, 5–6?, 6c, p.c., ?s, 5?, 0p, 2?'. The monophyletic grouping of ?pfiesteria-like? taxa within the order Peridiniales, as well as the grouping of Pfiesteria piscicida and Pfiesteria shumwayae within the same genus, is also supported by the preponderance of previous molecular evidence, and by the phylogenetic trees contributed in the present analysis. Pfiesteria appears to be closely related to as-yet informally described cryptoperidiniopsoids and calcareous dinoflagellates such as Thoracosphaera; thus, the family classification requires revision that is beyond the scope of this study.

Additional Information

Harmful Algae
Language: English
Date: 2006
Pfiesteria, Pfiesteria shumwayae, Electron microscopy, Morphology, Plate tabulation, Ribosomal genes, Phylogenetic trees; Taxonomy, Toxigenic

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