TY - JOUR

T1 - Morphological and phylogenetic data do not support the split of Alexandrium into four genera

AU - Mertens, Kenneth Neil

AU - Adachi, Masao

AU - Anderson, Donald M.

AU - Band-Schmidt, Christine J.

AU - Bravo, Isabel

AU - Brosnahan, Michael L.

AU - Bolch, Christopher J. S.

AU - Calado, António J.

AU - Carbonell-Moore, M. Consuelo

AU - Chomérat, Nicolas

AU - Elbrächter, Malte

AU - Figueroa, Rosa Isabel

AU - Fraga, Santiago

AU - Gárate-Lizárraga, Ismael

AU - Garcés, Esther

AU - Gu, Haifeng

AU - Hallegraeff, Gustaaf

AU - Hess, Philipp

AU - Hoppenrath, Mona

AU - Horiguchi, Takeo

AU - Iwataki, Mitsunori

AU - John, Uwe

AU - Kremp, Anke

AU - Larsen, Jacob

AU - Leaw, Chui Pin

AU - Li, Zhun

AU - Lim, Po Teen

AU - Litaker, Wayne

AU - MacKenzie, Lincoln

AU - Masseret, Estelle

AU - Matsuoka, Kazumi

AU - Moestrup, Øjvind

AU - Montresor, Marina

AU - Nagai, Satoshi

AU - Nézan, Elisabeth

AU - Nishimura, Tomohiro

AU - Okolodkov, Yuri B.

AU - Orlova, Tatiana Yu

AU - Reñé, Albert

AU - Sampedro, Nagore

AU - Satta, Cecilia Teodora

AU - Shin, Hyeon Ho

AU - Siano, Raffaele

AU - Smith, Kirsty F.

AU - Steidinger, Karen

AU - Takano, Yoshihito

AU - Tillmann, Urban

AU - Wolny, Jennifer

AU - Yamaguchi, Aika

AU - Murray, Shauna

PY - 2020

Y1 - 2020

N2 - A recently published study analyzed the phylogenetic relationship between the genera Centrodinium and Alexandrium, confirming an earlier publication showing the genus Alexandrium as paraphyletic. This most recent manuscript retained the genus Alexandrium, introduced a new genus Episemicolon, resurrected two genera, Gessnerium and Protogonyaulax, and stated that: “The polyphyly [sic] of Alexandrium is solved with the split into four genera”. However, these reintroduced taxa were not based on monophyletic groups. Therefore this work, if accepted, would result in replacing a single paraphyletic taxon with several non-monophyletic ones. The morphological data presented for genus characterization also do not convincingly support taxa delimitations. The combination of weak molecular phylogenetics and the lack of diagnostic traits (i.e., autapomorphies) render the applicability of the concept of limited use. The proposal to split the genus Alexandrium on the basis of our current knowledge is rejected herein. The aim here is not to present an alternative analysis and revision, but to maintain Alexandrium. A better constructed and more phylogenetically accurate revision can and should wait until more complete evidence becomes available and there is a strong reason to revise the genus Alexandrium. The reasons are explained in detail by a review of the available molecular and morphological data for species of the genera Alexandrium and Centrodinium. In addition, cyst morphology and chemotaxonomy are discussed, and the need for integrative taxonomy is highlighted.

AB - A recently published study analyzed the phylogenetic relationship between the genera Centrodinium and Alexandrium, confirming an earlier publication showing the genus Alexandrium as paraphyletic. This most recent manuscript retained the genus Alexandrium, introduced a new genus Episemicolon, resurrected two genera, Gessnerium and Protogonyaulax, and stated that: “The polyphyly [sic] of Alexandrium is solved with the split into four genera”. However, these reintroduced taxa were not based on monophyletic groups. Therefore this work, if accepted, would result in replacing a single paraphyletic taxon with several non-monophyletic ones. The morphological data presented for genus characterization also do not convincingly support taxa delimitations. The combination of weak molecular phylogenetics and the lack of diagnostic traits (i.e., autapomorphies) render the applicability of the concept of limited use. The proposal to split the genus Alexandrium on the basis of our current knowledge is rejected herein. The aim here is not to present an alternative analysis and revision, but to maintain Alexandrium. A better constructed and more phylogenetically accurate revision can and should wait until more complete evidence becomes available and there is a strong reason to revise the genus Alexandrium. The reasons are explained in detail by a review of the available molecular and morphological data for species of the genera Alexandrium and Centrodinium. In addition, cyst morphology and chemotaxonomy are discussed, and the need for integrative taxonomy is highlighted.

KW - Harmful algal blooms

KW - Paraphyletic

KW - Phylogenetics

KW - Saxitoxin

KW - Spirolides

KW - Taxonomy

U2 - 10.1016/j.hal.2020.101902

DO - 10.1016/j.hal.2020.101902

M3 - Journal article

C2 - 33129459

AN - SCOPUS:85090716409

VL - 98

JO - Harmful Algae

JF - Harmful Algae

SN - 1568-9883

M1 - 101902

ER -