New evidence for morphological and genetic variation in the cosmopolitan coccolithophore emiliania huxleyi (prymnesiophyceae) from the cox1b-atp4 genes

• Published in: Journal of Phycology
• Main Authors: Hagino, Kyoko, Bendif, El Mahdi, Young, Jeremy R., Kogame, Kazuhiro, Probert, Ian, Takano, Yoshihito, Horiguchi, Takeo, de Vargas, Colomban, Okada, Hisatake
• Other Authors: Evolution des Protistes et Ecosystèmes Pélagiques (EPEP), Adaptation et diversité en milieu marin (AD2M), Station biologique de Roscoff Roscoff (SBR), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Station biologique de Roscoff Roscoff (SBR), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Ministry of Education, Culture, Sports, Science and Technology, Japan, Japan Society for the Promotion of Sciences 20740296, EU FP7/2007-2013, FP7/227799
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2011
• Subjects: biogeography; coccolithophore; Emiliania huxleyi; mitochondrial DNA; morphotype; [SDV]Life Sciences [q-bio]; [SDE]Environmental Sciences; Pacific; North Atlantic; Subarctic
• Online Access: https://hal.science/hal-01258248; https://doi.org/10.1111/j.1529-8817.2011.01053.x

International audience Emiliania huxleyi (Lohmann) W. W. Hay et H. Mohler is a cosmopolitan coccolithophore occurring from tropical to subpolar waters and exhibiting variations in morphology of coccoliths possibly related to environmental conditions. We examined morphological characters of coccoliths and partial mitochondrial sequences of the cytochrome oxidase 1b (cox1b) through adenosine triphosphate synthase 4 (atp4) genes of 39 clonal E. huxleyi strains from the Atlantic and Pacific Oceans, Mediterranean Sea, and their adjacent seas. Based on the morphological study of culture strains by SEM, Type O, a new morphotype characterized by coccoliths with an open central area, was separated from existing morphotypes A, B, B/C, C, R, and var. corona, characterized by coccoliths with central area elements. Molecular phylogenetic studies revealed that E. huxleyi consists of at least two mitochondrial sequence groups with different temperature preferences/tolerances: a cool-water group occurring in subarctic North Atlantic and Pacific and a warm-water group occurring in the subtropical Atlantic and Pacific and in the Mediterranean Sea.