Diatoms of the Academy of Natural Sciences of Drexel University

They are invisible to the naked eye. But once revealed, they are each a unique geometrical marvel of nature.

By Academy of Natural Sciences of Drexel University

Navicula oamaruensis light microscope by Marina PotapovaAcademy of Natural Sciences of Drexel University

Beautiful Algae

Diatoms (Bacillariophyceae) are water-dwelling microscopic photosynthetic organisms—algae—with elaborate glass shells. In other words, they are tiny plants (although some of them can move) that live in beautiful glass houses in water.

Biddulphia inflata var. recta by Marina PotapovaAcademy of Natural Sciences of Drexel University

Glass Houses

These glass houses are of many sizes and shapes, with spines, pores and slits, but they are always made of two pieces (called valves). Diatoms are found anywhere where there is at least one drop of water. That means streams, oceans, sewage water, and also wet rocks, backyard pools, and a manatee's skin.

Auliscus oamaruensis by Marina PotapovaAcademy of Natural Sciences of Drexel University

Although very small in size, they are essential for all living organisms. Diatoms living just in the oceans are responsible for producing about a quarter of the world’s production of oxygen, which all living things need to survive.

Triceratium castillatum var. fasta by Marina PotapovaAcademy of Natural Sciences of Drexel University

The Diatom Herbarium at the Academy of Natural Sciences of Drexel University is one of the two largest such collections in the world; the other is at the Natural History Museum, London.

Triceratium pulvinar by Marina PotapovaAcademy of Natural Sciences of Drexel University

The Academy’s collection includes 220,000 slides, of which 5,000 are types, and much of it is available in an online database.

Actinocyclus ralfsii by Marina PotapovaAcademy of Natural Sciences of Drexel University

The collection, dating back before the 1800s, is a primary source of taxonomic and ecological information.

Biddulphia arctic var. pentagona by Marina PotapovaAcademy of Natural Sciences of Drexel University

Navicula oamaruensis light microscope by Marina PotapovaAcademy of Natural Sciences of Drexel University

Staurosirella sp. by Eduardo MoralesAcademy of Natural Sciences of Drexel University

Detail of areolae on the surface of Epithemia sp. by Marina PotapovaAcademy of Natural Sciences of Drexel University

Amphora sp by Eduardo MoralesAcademy of Natural Sciences of Drexel University

Didymosphenia geminata by Eduardo MoralesAcademy of Natural Sciences of Drexel University

Opephora sp. by Eduardo MoralesAcademy of Natural Sciences of Drexel University

Cocconeis sp. by Eduardo MoralesAcademy of Natural Sciences of Drexel University

Planothidium sp. by Nina DesiantiAcademy of Natural Sciences of Drexel University

Biremis circumtexta by Eduardo MoralesAcademy of Natural Sciences of Drexel University

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