Hymenophyllum
Quick Summary
The genus Hymenophyllum belongs to the family Hymenophyllaceae, commonly known as filmy ferns. These are small, delicate ferns, often found growing on other plants (epiphytes). Their leaves are typically only one cell layer thick between the veins.1
Hymenophyllum is distinguished from a related genus, Trichomanes, by the structure of its sporangia (spore-producing structures) and their protective covering, called an involucre. Filmy ferns are considered an ancient and relatively primitive group of ferns, though their delicate nature means their fossil record is sparse. They are primarily found in tropical regions worldwide.21
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