Kopakopa / Kidney fern (Hymenophyllum nephrophyllum)

Hymenophyllum nephrophyllum is a fern distinctive for its undivided, kidney-shaped fronds, which give the plant its English common name, the kidney fern. The fronds, or laminae, are 3–10 cm by 4–13 cm and are a shiny, translucent green. The translucent nature of the kidney fern’s fronds is due to them being very thin, only one cell thick as a sporeling, which increases to 3-4 cells when the plant reaches maturity. The fronds are supported on brittle stipes 5–25 cm in length. Mature plants.. more