Cocconeis rouxii Héribaud & Brun a forgotten, but common benthic diatom species from the Massif Central, France

Abstract

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Integrative taxonomic description of two new species of the Cocconeis placentula group (Bacillariophyceae) from Korea based on unialgal strains

“…In addition, further important features such as valvocopula structure (open or closed, with or without fimbriae), and occlusion structures (hymenes or vela) of the areolae (Holmes et al 1982) are missing as in many other publications including some of our own (i.e., Romero and Jahn 2013). A recent paper lectotypifies an old taxon named C. rouxii Héribaud & Brun with an apparently restricted occurrence in the Massif Centrale, France, which also used to be regarded as a variety of C. placentula; the SEM pictures with details on valvocopulae, fimbriae, and hymenes of RV and SV demonstrate that detailed SEM studies can support the differentiation of taxa in this group (Wetzel et al 2019). Another recent paper describes a new species from California, C. cascadensis Stancheva, and detailed SEM findings show that this differentiation seems justified (Stancheva 2019).…”

“…This is in contrast to the new species C. sijunghoensis which we found only in one year in one water body in North Korea and for which we could find no real match in the presented data and morphologically similar taxa is difficult because, on the one hand, our study provides no data on the morphological variability of the newly described species in the environment before undergoing cultivation. On the other hand, no material derived from clonal culturing is available in current studies on freshwater Cocconeis taxa (e.g., Stancheva 2019, Wetzel et al 2019, Costa et al 2020. For this reason, molecular data are missing and morphological changes during the life cycle have not been documented.…”

Community of Phytoplankton as Aquatic Quality Bioindicator in Teluk Melanau Waters Lemukutan Island West Kalimantan

“…Hal ini dapat dilihat bahwa genus tersebut dapat ditemukan di semua titik pengambilan sampel dengan kelimpahan tinggi, yaitu Cocconeis (1521 ind/L), Nitzchia (1340 ind/L), Synedra (892 ind/L), dan Chaetoceros (853 ind/L). Dominasi Cocconeis telah banyak dilaporkan oleh beberapa penelitian sebelumnya (Wetzel et al, 2019;Tarigas et al, 2020). Hal ini disebabkan karena jenis tersebut memiliki tingkat reproduksi tinggi, daya kolonisasi dan pelekatan kuat pada permukaan substrat (Gacia et al, 2009).…”