Asterionella formosa has coarse striae with a capitate foot pole and a rounded head pole. Asterionella ralfsii and A. ralfsii var. hustedtiana have rounded head poles and larger mid-valve widths.
Diatoms of North America is running a fundraising campaign to keep the servers in operation. We need you to reach our $25,000 fundraising goal.
If you use and appreciate DONA, make your DONAtion today.
For the Gift Designation, type "diatom" in the search box and select "Diatom Lab Research Fund". This is the designated fund for diatoms.org.