In the process of automated whole-slide imaging, we found that large species are easily detected even using a 10x objective lens. Yet, large species are typically missed in traditional surveys for diatoms. In this study we are examining microslides from the ANSP Herbarium representing ~700 lakes in the northeastern US and Canada. The materials represent recent to Quaternary lake sediments.

Large species, such as many Pinnularia species, are poorly represented in studies. However these large specimens represent a diverse and valuable flora of minimally disturbed sites. Many of the sediments are from sections prior to human settlement, so they are the best representatives of reference, or undisturbed conditions.

We expect that these taxa are a valuable, but as yet under utilized measure of diatom biodiversity. Automated whole-slide imaging offers a means to track species loss due to human influence in these northeastern watersheds.


  • National Science Foundation

    award title - Marina Potapova


Marina Potapova

Content Editor, Monoraphid Diatoms Diatoms of North America, Editoral Review Board

Curator Diatom Herbarium, Academy of Natural Sciences of Philadelphia, Drexel University

Naomi Friedman

Undergraduate Student Drexel University

Micaela Kersey

Undergraduate Student Dexel University

Laura Aycock

Content Editor Diatoms of North America, Editoral Review Board

Collections Manager Academy of Natural Sciences of Drexel University

Cassidy Joyce

Undergraduate Drexel University

Pinnularia formica SEM ME 10011unfiltered 041918 Mix 010
Pinnularia formica
Pinnularia torta guide
Image Credit: M. Potapova
Pinnularia torta