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 viridulacalcis subsp. neomundana


155 Completed
19 Underway
777 Completed
186 Underway

Getting Started

About this website

What are diatoms?

Identify your taxa

Special News

25 March, 2011

Information for contributors


12 August, 2016

When art and diatoms collide

15 April, 2016

Track new content on DOTUS

More news...


From a playful summer camp…

U.S. Geological Survey / Academy of Natural Sciences of Philadelphia

Diatoms from the Crown of the Continent

More projects...