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Analysis of type material of Opephora pacifica and emendation of the genus Opephora (Bacillariophyta)

Eduardo A. Morales ORCID logo, Carlos E. Wetzel, Luc Ector and Bart Van de Vijver
From the journal Botanica Marina


The genus Opephora currently contains 37 species and 27 infraspecific taxa. However, the existing literature reveals a wide morphological diversity and the need to establish defining characters to circumscribe the genus as a cohesive and, perhaps, monophyletic group. The type material of Opephora pacifica, the generitype, is analysed. We emend the description of both the species and the genus, the latter also based on published light and scanning electron microscopy observations of closely related species. After review of the available literature, we determined that currently only two species can be ascribed with certainty to the genus Opephora: O. pacifica and O. marina. Based on available literature, it is highly likely that O. fragilarioides also belongs to this genus. We present a table with all known species and infraspecific taxa and make comments regarding their recent transfer to other genera, their current accepted nomenclature, and the genus to which they should probably be ascribed pending the collection of further information.

Corresponding author: Eduardo A. Morales, Water Laboratory, University of Évora, P.I.T.E. Rua da Barba Rala No. 1, 7005–345Évora, Portugal; and Institute of Earth Sciences – ICT, University of Évora, Rua Romão Ramalho 59, 7000–671Évora, Portugal, E-mail:

Funding source: European Regional Development Fund

Award Identifier / Grant number: UID/GEO/04683/2013

Funding source: LIST-Luxembourg Institute of Science and Technology

  1. Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.

  2. Research funding: This work was co-funded by the European Union through the European Regional Development Fund, framed within the Operational Programme Competitiveness and Internationalization, COMPETE 2020 through the ICT project (UID/GEO/04683/2013) with reference POCI-01-0145-FEDER-007690 and the Agencia Portuguesa do Ambiente, APA-000004DFIN.AALP/2017 integrated within the Operational Program for Sustainability and Efficiency in the Use of Resources 2014-20, POSEUR-03-2013-FC-000001. Funding for this research was also partly provided in the framework of the DIATOMS project (LIST-Luxembourg Institute of Science and Technology).

  3. Conflict of interest statement: The authors declare no conflicts of interest regarding this article.


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Received: 2020-05-11
Accepted: 2020-12-09
Published Online: 2021-01-06
Published in Print: 2021-02-23

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