Morphology of Australoneis gen. nov. and A. frenguelliae comb. nov. (Achnanthales, Bacillariophyta) from the Antarctic Peninsula

• Published in: Phytotaxa
• Main Authors: Guerrero, José, Riaux-Gobin, Catherine, Debandi, Juan, Zacher, Katharina, Quartino, Maria Liliana, Campana, Gabriela
• Other Authors: Centre de recherches insulaires et observatoire de l'environnement (CRIOBE), Université de Perpignan Via Domitia (UPVD)-École Pratique des Hautes Études (EPHE), Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Excellence CORAIL (LabEX CORAIL), Institut de Recherche pour le Développement (IRD)-Université des Antilles et de la Guyane (UAG)-École des hautes études en sciences sociales (EHESS)-École Pratique des Hautes Études (EPHE), Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de La Réunion (UR)-Université de la Polynésie Française (UPF)-Université de la Nouvelle-Calédonie (UNC)-Institut d'écologie et environnement-Université des Antilles (UA)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2021
• Subjects: [SDE.BE]Environmental Sciences/Biodiversity and Ecology; Antarc*; Antarctic; Antarctic Peninsula
• Online Access: https://univ-perp.hal.science/hal-03658029; https://doi.org/10.11646/phytotaxa.513.2.1

International audience Based on marine benthic diatoms collected at Potter Cove (Western Antarctic Peninsula), we present a detailed study, using both light and electron microscopy, of the morphology of Campyloneis frenguelliae, a species recently transferred from Cocconeis. Ultrastructural observations revealed a combination of new and unusual features within the Achnanthales: a raphe valve with different areolation patterns, a hollow valvocopula with no apparent fimbriae, and a sternum valve externally ornamented by an embossed structure, areolae occluded by hymenes mostly supported by one short peg, and multiple marginal pores that open internally into shallow valve depressions. In view of these unique set of features, we describe Australoneis gen. nov. to include Australoneis frenguelliae comb. nov. and designate a sample from Potter Cove as epitype of the latter. The main characteristics of the new genus are compared to those of its closely allied Cocconeis, Campyloneis, Xenococconeis and Amphicocconeis.