Photo of the Day

Freshwater fish species
April 2, 2010

Ouachita Madtom

This Month in Photo of the Day: Nature and Environment

The finger-length Ouachita madtom lives only in the Saline River in Arkansas.
Noturus lachneri


See more photographs from the April 2010 National Geographic feature story "Silent Streams."

Photograph by Joel Sartore

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