Introduction to Bacillariophyta (The Diatoms)
Life inside a glass box. . .
The Bacillariophyta are the diatoms. With their exquisitely beautiful silica shells, or
such as that of
shown above at right, diatoms are among the loveliest microfossils. They are also among the most important aquatic microorganisms today: they are extremely abundant both in the plankton and in sediments in marine and freshwater ecosystems, and because they are
they are an important food source for marine organisms. Some may even be found in soils or on moist mosses.
Diatoms have an extensive fossil record going back to the Cretaceous; some rocks are formed almost entirely of fossil diatoms, and are known as diatomite or
. These deposits are mined commercially as abrasives and filtering aids. Analysis of fossil diatom assemblages may also provide important information on past environmental conditions.
Click on the buttons below to learn more about the Diatoms.
You can search the
UCMP micropaleontology type collection
For more information on diatoms and how they are used in environmental reconstruction, check out the
Paleolimnology and Diatom Home Pages
maintained by P. Roger Sweets at Indiana University, or visit the
Algal Microscopy and Image Digitization Home Page
at Bowling Green State University for many images of diatoms.
You might also want to visit the
of the California Academy of Sciences, including databases on diatom genera and literature.
article on diatoms
(15 Sep 1997) is available from the Mining Company.
Image of living diatom courtesy Virtual Foliage at the University of Wisconsin. Electron micrograph of
taken by Karen Wetmore at UCMP.