118
Views
0
CrossRef citations to date
0
Altmetric
Research Article

Systematic reappraisal of the diminutive Amphora thumensis and the transfer of Halamphora parathumensis to the genus Amphora

, , &
Pages 135-142 | Received 07 Jul 2023, Accepted 31 Aug 2023, Published online: 17 Oct 2023
 

Abstract

Since its description the amphoroid diatom Amphora thumensis has confounded simple taxonomic classification having been assigned to Amphora, Cymbella, and now Halamphora. Taxonomic ambiguity around this taxon stems from its small size and reduced, often contradictory, morphological features. In this investigation, we confirm the taxonomic position of A. thumensis by presenting a four-marker molecular phylogeny for a population collected from a small spring-fed lake in the Rocky Mountains of Colorado, USA. Our phylogenetic hypothesis places A. thumensis not within the genus Halamphora, but within the deep branching lineages of Amphora. We discuss this phylogenetic hypothesis in the context of the morphological and ecological diversity of the genus and evaluate the utility of putative diagnostic characters within Amphora. In light of this new evidence, the valid name Amphora thumensis (Mayer) Krieger is identified as the preferred designation for this taxon. Consequently, we transfer the morphologically similar Halamphora parathumensis to Amphora.

Disclosure statement

No potential conflict of interest was reported by the authors.

Supplemental data

Supplemental data for this article can be accessed at https://doi.org/10.1080/0269249X.2023.2265380.

Additional information

Funding

The authors would like to thank the Vail Valley campus of Colorado Mountain College for project funding.

Reprints and Corporate Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

To request a reprint or corporate permissions for this article, please click on the relevant link below:

Academic Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

Obtain permissions instantly via Rightslink by clicking on the button below:

If you are unable to obtain permissions via Rightslink, please complete and submit this Permissions form. For more information, please visit our Permissions help page.