Cyathea planadae, a remarkable new creeping tree fern from Colombia, South America

A new species within the Cyathaceae is described from the mid-elevation cloud forests of the Andes in southwestern Colombia. Cyathea planadae N.C. Arens & A.R. Smith has fragile, ephemeral, sphaeropteroid indusia surrounding inframedial to medial sori, which are typical of many Cyathea; however it is unusual in possessing a creeping stem. Decumbent stems (above-ground rhizomes) bearing adventitious roots and buds give rise to narrow, glabrous upright shoots upon which three or four twice-pinnate-pinnatified fronds are typically displayed. Cyathea planadae is very common and patchily distributed in the understory of primary forest habitats in montane forests. The species is also noteworthy for an apparent association with an ant species, which appears to feed from pads of tissue at the base of the pinnae.