Fronds boat-shaped, 0.5--1.6 mm, 1--1.5 times as long as wide, 0.3--0.7 times as deep as wide, rounded at apex, papilla usually prominent in center of upper surface (tent-shaped); upper surface intensely green, with 50--100 stomates; pigment cells present in vegetative tissue (visible in dead fronds as brown dots). 2n = 20, 40, 42, 50, 60, 80.