Air fern
From Wikipedia, the free encyclopedia
| iAir fern | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Scientific classification | ||||||||||||||
|
||||||||||||||
|
|
||||||||||||||
| Sertularia argenta (Linnaeus, 1758) |
Air ferns (Sertularia argenta) are commonly sold as a curiosity or a decorative "indoor plant", and as underwater decorations for aquaria in stores, and are labeled as "air ferns". Air ferns do not grow, have any roots, or even have leaves, as they are not even plants, but small dead and dried colonies of small animals called hydrozoans that have been dyed green. If soaked in water, the green coloring will dissolve. They belong to the phylum Cnidaria, class Hydrozoa. The fernlike branches of S. argenta are composed of many, small, chitinous chambers where individual animals once lived. When the colony was alive, a polyp with numerous tentacles occupied each of the chambers, called hydrotheca. Most commercial air ferns are collected by trawlers in the North Sea.
