Ferocia gen. nov., a new centric diatom genus (Bacillariophyceae) from the sub-Antarctic region

• Published in: Phytotaxa
• Main Authors: van de Vijver, Bart, Chattova, Barbora, Lebouvier, Marc, Houk, Vaclav
• Other Authors: University of Antwerp (UA), Masaryk University Brno (MUNI), Ecosystèmes, biodiversité, évolution Rennes (ECOBIO), Université de Rennes (UR)-Institut Ecologie et Environnement - CNRS Ecologie et Environnement (INEE-CNRS), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS), Institute of Botany of the Czech Academy of Sciences (IB / CAS), Czech Academy of Sciences Prague (CAS), French Polar Institute Paul-Emile Victor 136, Academy of Sciences of the Czech Republic AV0Z60050516, Czech Science Foundation 205/05/0204
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2017
• Subjects: centric diatoms; new genus; Melosira; Ferocia; sub-Antarctic Region; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; Antarctic; Indian; Antarc*
• Online Access: https://univ-rennes.hal.science/hal-01684481; https://doi.org/10.11646/phytotaxa.332.1.2

International audience A new centric diatom genus, Ferocia Van de Vijver and Houk gen. nov. is described based on Melosira setosa Greville. Several samples collected in lava tunnels on Ile Amsterdam, a small isolated, volcanic island in the southern Indian Ocean where the latter taxon dominated the diatom flora, were investigated. The new genus is characterized by having heavily silicified, spherical frustules, connected into long chains by large, complex linking spines. Valves are dome-shaped with a high mantle with rounded to irregularly shaped areolae. Numerous small rimoportulae forming a marginal ring are present near the mantle edge. The cingulum is composed of a large number of narrow, open copulae. A second species, Ferocia ninae Van de Vijver and Houk sp. nov., is described from the nearby Crozet archipelago. Besides the typical features of the genus Ferocia, the rimoportulae in F. ninae are almost equidistant, the valves have a relatively low valve height and the spines are relatively small. Both F. ninae and F. setosa were found in shaded lava tunnels with a sparse moss vegetation. The two species are illustrated and discussed based on detailed LM and SEM observations.