Jana Kulichova’s Choice: Diatom Research article to ring in the new year

by Jana Kulichova |

As the first issue of Diatom Research in 2025 is dedicated to biogeography, and because biogeography fundamentally depends on reliable species identification, I have selected to promote a paper by David M. Williams that addresses the taxonomic obstacles affecting our understanding of species distributions. The title, ‘Ubiquitous Names and Ubiquitous Species’, reflects a key theme: Are diatom species truly cosmopolitan, or have their names become more widespread than the species themselves? In other words, what if the broad distributions that have been assumed for decades are artefacts of taxon names that have been widely applied to superficially similar specimens around the world? By revisiting the foundations of the Synedra and Ulnaria taxa, David M. Williams demonstrates how historical naming practices, such as inadequate diagnoses, ambiguous characteristics, and misidentifications, can obscure true diversity and complicate our understanding of evolutionary and biogeographical patterns.

ABTRACT
The term ‘Ubiquitous name’ is created and discussed. A ‘ubiquitous name’ is a taxon name that is used for any specimens that are superficially classified with a ‘commonly adopted name’ such as Synedra acus (Ulnaria acus) and Synedra ulna (Ulnaria ulna). Two examples are provided. The first, from 1923, is Joaquin Frenguelli and his use of the name Synedra acus for the diatoms of Argentina. The second, 100 years later, from 2023, Kochoska et al.’s use of the name Synedra goulardii. With reference to historical biogeography, ‘ubiquitous names’ can only be successfully eliminated with revisionary monographic treatments of the geographical spread of taxa within some specific area. Historical biogeography requires schemes of taxon relationships so that one might be able to understand how, specifically, species relate in these different areas.

CITATION
David M. Williams (2025) Ubiquitous names and ubiquitous species: examples from Synedra acus (Ulnaria acus), S. ulna (Ulnaria ulna) and S. goulardii (Ulnaria goulardii), Diatom Research 40(1): 81-92, DOI: 10.1080/0269249X.2024.2412849