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 also included.

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

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

Navicula cryptocephaloides


155 Completed
19 Underway
814 Completed
199 Underway
1013 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


01 February, 2017

The Gomphonema Round Up Taxon Workshop

20 January, 2017

Citizen Scientists Lend a Hand

More news...


Alverson Lab, University of Arkansas

Atmospheric deposition of nitrogen and its effects on diatoms

Ecology and Systematics of Diatoms course, 2012

More projects...