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Alexandrium diversaporum sp. nov., a new non-saxitoxin producing species: Phylogeny, morphology and sxtA genes


Murray, SA and Hoppenrath, M and Orr, RJS and Bolch, C and John, U and Diwan, R and Yauwenas, R and Harwood, T and de Salas, M and Neilan, B and Hallegraeff, G, Alexandrium diversaporum sp. nov., a new non-saxitoxin producing species: Phylogeny, morphology and sxtA genes, Harmful Algae, 31 pp. 54-65. ISSN 1568-9883 (2014) [Refereed Article]

Copyright Statement

Copyright 2013 Elsevier

DOI: doi:10.1016/j.hal.2013.09.005


Species of the PST producing planktonic marine dinoflagellate genus Alexandrium have been intensively scrutinised, and it is therefore surprising that new taxa can still be found. Here we report a new species, Alexandrium diversaporum nov. sp., isolated from spherical cysts found at two sites in Tasmania, Australia. This species differs in its morphology from all previously reported Alexandrium species, possessing a unique combination of morphological features: the presence of 2 size classes of thecal pores on the cell surface, a medium cell size, the size and shape of the 6", 1', 2"" and Sp plates, the lack of a ventral pore, a lack of anterior and posterior connecting pores, and a lack of chain formation. We determined the relationship of the two strains to other species of Alexandrium based on an alignment of concatenated SSU-ITS1, 5.8S, ITS2 and partial LSU ribosomal RNA sequences, and found A. diversaporum to be a sister group to Alexandrium leei with high support. A. leei shares several morphological features, including the relative size and shapes of the 6", 1', 2"" and Sp plates and the fact that some strains of A. leei have two size classes of thecal pores. We examined A. diversaporum strains for saxitoxin production and found them to be non-toxic. The species lacked sequences for the domain A4 of sxtA, as has been previously found for non-saxitoxin producing species of Alexandrium.

Item Details

Item Type:Refereed Article
Keywords:toxic algae, Alexandrium diversaporum, phylogenetics, PSP, PST, saxitoxin, sxtA, systematics
Research Division:Biological Sciences
Research Group:Plant biology
Research Field:Phycology (incl. marine grasses)
Objective Division:Animal Production and Animal Primary Products
Objective Group:Fisheries - aquaculture
Objective Field:Fisheries - aquaculture not elsewhere classified
UTAS Author:Bolch, C (Associate Professor Christopher Bolch)
UTAS Author:de Salas, M (Dr Miguel de Salas)
UTAS Author:Hallegraeff, G (Professor Gustaaf Hallegraeff)
ID Code:86796
Year Published:2014
Web of Science® Times Cited:19
Deposited By:IMAS Research and Education Centre
Deposited On:2013-10-22
Last Modified:2017-11-02

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