Molecular and morphological criteria for revision of the genus Microcoleus (Oscillatoriales, Cyanobacteria). Issue 6 (14th November 2013)

• Record Type: Journal Article
• Authors: Strunecký, Otakar; Komárek, Jiří; Johansen, Jeffrey; Lukešová, Alena; Elster, Josef; Post, A.
• Is Part Of: Journal of phycology. Volume 49:Issue 6(2013:Dec.)
• Page Start: 1167
• Page End: 1180
• Publication Date: 2013-11-14
• Subjects: Algae -- Periodicals; 579.8
• DOI: 10.1111/jpy.12128
• Languages: English
• ISSNs: 0022-3646

Abstract

<abstract abstract-type="main" id="jpy12128-abs-0001"> <title> <x xml:space="preserve">Abstract</x> </title> <p>Ninety‐two strains of <italic>Microcoleus vaginatus</italic> (=nomenclatural‐type species of the genus <italic>Microcoleus</italic> Desmazières ex Gomont) and <italic>Phormidium autumnale</italic> Trevisan ex Gomont from a wide diversity of regions and biotopes were examined using a combination of morphological and molecular methods. Phylogenies based on the 16S rDNA and 16S‐23S ITS (partial) demonstrated that the 92 strains, together with a number of strains in GenBank, were members of a highly supported monophyletic clade of strains (Bayesian posterior probability = 1.0) distant from the species‐cluster containing the generitype of <italic>Phormidium</italic>. Similarity of the 16S rRNA gene exceeded 95.5% among all members of the <italic>Microcoleus</italic> clade, but was less than 95% between any <italic>Microcoleus</italic> strains and species outside of the clade (e.g., <italic>Phormidium sensu stricto</italic>). These findings, which are in agreement with earlier studies on these taxa, necessitate the revision of <italic>Microcoleus</italic> to include <italic>P. autumnale</italic>. Furthermore, the cluster of <italic>Phormidium</italic> species in the <italic>P. autumnale</italic> group (known as Group VII) must be moved into <italic>Microcoleus</italic> as well, and these nomenclatural transfers are included in this study. The main diacritical characters defining <italic>Microcoleus</italic> are related to the cytomorphology of trichomes, including: narrowed trichome ends, calyptra, cells shorter than wide up to more or less isodiametric, and facultative presence of sheaths. The majority of species are 4–10 μm in diameter. The possession of multiple trichomes in a common sheath is present facultatively in many but not all species.</p> </abstract>