Diatom of the Month November 2018 - Diatoms of North America

Diatoms of North America, a unique resource for scientists and managers

Which technician, scientist or practitioner has never used Google to look for useful images to identify their diatom specimens? In 2010, a new diatom online flora, “Diatoms of the United States” was launched to document diatom genera and species in the United States, as well as North America. Since then, the quality of images and descriptions and the number of contributed species have consistently increased thus supporting correct identification of diatoms. In 2018, the Version 2, called “Diatoms of North America”, was completed with design improvement and new dynamic tools based on feedback from practitioners. Diatoms of North America is a collaborative effort to document the diversity of diatom species in North America and provide accurate information on diatom identification, ecology and distribution (Spaulding et al. 2018). This unique online platform helps federal, tribal, state and local agencies assess their waters according to high scientific standards ensured by the Editorial Review Board (Mark Edlund, Marina Potapova, Sylvia Lee, Ian Bishop and Sarah Spaulding). The project has been partially funded by US EPA, USGS, the Institute of Arctic and Alpine Research at University of Colorado Boulder and other organizations.

Didymosphenia geminata mat. Source: diatoms.org 

On Diatoms of North America, you can find 24 projects that include courses, regional monitoring and research activities, student initiatives and outreach endeavors, including arts. Ecology and Systematics of Diatoms is among the most important and longest running diatom courses (56th annual edition in 2018). Once a year, students around the world work in the Iowa Lakeside Laboratory to complete training in diatom research and apply their new in-depth knowledge of diatoms to produce taxon pages for the website as a final project. The Phycological Research Consortium (PCR) provides a network through biannual meetings to interchange ideas and address algal research issues in a collaborative and fun atmosphere. Diatoms of North America also works with citizen scientists by producing new additions on diatom ecology and taxonomy from remote areas of North America.

To date, a wealth of 130 taxon contributors have provided taxon pages on 930 species from 160 genera so far (e.g. 83 species of Navicula!), including 6 contributors who wrote > 100 pages and 17 who wrote 10-99 pages on diatom taxa. Species described are also classified by morphology: centric, araphid, symmetrical biraphid (59 genera), asymmetrical biraphid, eunotioid, monoraphid, epithemioid, nitzschioid, and surirelloid. If you want to contribute a new taxon page, you need to provide the following: correct taxon name, nomenclatural synonyms of the taxon, high quality images; a clearly written description of the important morphological features of the taxon; original description with text and iconotype; diagnostic section; literature citations; autecological data. More detailed information of contributors can be found here. The website lists ~160 technical terms (e.g. costa, epitheca, keel, pore field) in a very useful glossary, and more terms are continuing to be added. Importantly, Diatoms of North America helps practitioners with: (i) taxon updates (63 provided so far); (ii) a list of 240 standardized authorship names, autoecology tags to classify diatom species according to their size, motility, attachment, habitat, distribution and other features; (iii) and review guidelines for experts to help improve their colleagues’ diatom species descriptions for the taxon pages.

An important ongoing initiative is the creation of a Diatom Taxonomic Certification Program (TCP) to test knowledge and skills in diatom taxonomy and certify proficient diatomists. Do not forget about the North American Diatom Symposium 2019 that will take place from July 31 to August 4 next year at the University of Georgia’s Rock Eagle 4-H Center in Eatonton, Georgia.

Photo from the taxon update on Psammodictyon (Photo by Ian Bishop of Psammodictyon panduriforme (W.Greg.) D.G.Mann).

Last but not least, the “What are Diatoms?” page informs / reminds any interested person that diatoms produce 25-40% of the air we breathe, that they feed the oceans, lakes and rivers, that diatoms are the most diverse protists on earth and that they Diatoms tell us about the health of aquatic systems, all in simple language and with great pictures. Enjoy Diatoms of North America! 

By Luca Marazzi, Xavier Benito, Sylvia Lee and Sarah Spaulding

References

Spaulding, S.A., Bishop, I.W., Edlund, M.B., Lee, S. and Potapova, M. 2018. Diatoms of North America. https://diatoms.org/