Diatom identification guide & ecological resource

for water resource managers, ecologists, taxonomists, analysts, systematists, students, and the public.

We aim to provide everyone with accurate information about diatoms of the United States.

Expert contributors are submitting text and images for freshwater genera and North American species, including taxonomic and ecological information.

Diatom "visual guides" are included for all taxa.  The guides illustrate key traits that distinguish a taxon (examples to the right). For many species, environmental response plots and geographic distribution maps are included.

Our editorial review board is prioritizing taxa for treatment in species pages and ensuring the scientific merit of each submission.

See issues with content or functionality? If so,  please let us know.

Navicula kotschyi


157 Completed
22 Underway
883 Completed
188 Underway
1071 TOTAL

Getting Started

About this website

What are diatoms?

Identify your taxa

Special News

26 June, 2015

Editorial Review Guidelines

25 March, 2011

Information for contributors


13 February, 2018

Tiny fossils, huge slides

07 August, 2017

North American Diatom Symposium 2017

More news...


Southeast Stream Quality Assessment

Phycological Research Consortium

Ecology and Systematics of Diatoms course, 2015

More projects...