Water fern (Azolla filiculoides) is a floating aquatic fern native to tropical regions of the Americas but introduced in many regions on the World. Az

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Water fern (Azolla filiculoides) is a floating aquatic fern native to tropical regions of the Americas but introduced in many regions on the World. Azolla can fix nitrogen from the air thanks to symbiosi with the cyanobacterium Anabaena azollae. Pteridophyta. Azollaceae. Salviniaceae. This photo was taken in Arribes del Duero Natural Park, Zamora, Spain.

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Size: 4256px × 2832px
Photo credit: © José María Barres Manuel / Alamy / Afripics
License: Royalty Free
Model Released: No

Keywords: anabaena, aquatic, arribes, azolla, azollaceae, azollae, botany, castilla, close, cryptogams, cyanobacterium, del, duero, fern, filiculoides, floating, horizontal, leon, natural, nitrogen-fixing, park, pteridophyta, saliviniaceae, spain, symbiosis, water, zamora