Juvenile morphology of the large Antarctic canopy-forming brown alga, Desmarestia menziesii J. Agardh

• Published in: Polar Biology
• Main Authors: Küpper, Frithjof, Amsler, Charles, Morley, Simon, De Reviers, Bruno, Reichardt, Aurelia, Peck, Lloyd, Peters, Akira
• Other Authors: University of Aberdeen, University of Alabama at Birmingham Birmingham (UAB), British Antarctic Survey (BAS), Natural Environment Research Council (NERC), Institut de Systématique, Evolution, Biodiversité (ISYEB ), Muséum national d'Histoire naturelle (MNHN)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA), Bezhin Rosko
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2019
• Subjects: Adelaide Island; Antarctic Peninsula; Desmarestia chordalis; Desmarestia menziesii; Desmarestia rossii; ITS; Southern Ocean; [SDV]Life Sciences [q-bio]; Antarctic; Anvers; Anvers Island; Marguerite; Marguerite Bay; Rothera; Rothera Research Station; The Antarctic; Antarc*; Antarctica; Polar Biology
• Online Access: https://hal.sorbonne-universite.fr/hal-02344817; https://hal.sorbonne-universite.fr/hal-02344817/document; https://hal.sorbonne-universite.fr/hal-02344817/file/K%C3%BCpper2019_Article_JuvenileMorphologyOfTheLargeAn.pdf; https://doi.org/10.1007/s00300-019-02584-3

International audience For many types of seaweeds in Polar Regions, open questions remain about how their life cycle contributes to their overall adaptation to the extreme abiotic environment. This applies in particular to the major canopy-forming brown algae in much of the Antarctic Peninsula of the genus Desmarestia, which was investigated here. Diving surveys around Rothera Research Station (Adelaide Island, Antarctica) during December 2017-February 2018 revealed the widespread presence of a hitherto-unknown life form of Desmarestia sp. of a tender, feather-like morphology. Further studies explored whether this could be (1) a new, hitherto undescribed Desmarestia species (2) a new record for the region of a known Desmarestia species previously recorded elsewhere or (3) a so-far unknown life form of a species recorded for the region. Collections enabled the extraction of PCR-friendly DNA and sequencing of ITS1, which unambiguously showed that the samples belonged to Desmarestia menziesii, the only Desmarestia species presently recorded for the Adelaide Island/Marguerite Bay region. The presence of the juvenile morphology was subsequently confirmed throughout much of the natural range of D. menziesii during cruise-based diving surveys along the Western Antarctic Peninsula in 2019 and from collections at Anvers Island in 1989. Our collections thus constitute its juvenile morphology, which is not previously documented in the literature. The wider significance for the Polar seaweeds is discussed in the context of Taxonomy and Ecology.