About Selaginella willdenowii (Desv.) Baker
Species Identification
This species, Selaginella willdenowii, has blue iridescence on its leaves.
Iridescence Formation Mechanism
The iridescence forms through thin-film interference in a thin layer of lamellar-structured cells located in the upper cuticle of the leaves.
Iridescence Adaptive Function
Researchers suggest this iridescence is an adaptation that lessens the impact of strong sunlight that filters through the forest canopy; without this adaptation, the strong light would damage this shade-adapted species.
Related Iridescent Species
Blue iridescence is also seen in Selaginella uncinata, and both of these species are adapted to grow in the extreme shade beneath forest canopies.
