It is not rare. Not yet. But the sickle spleenwort faces increasing pressure from habitat degradation throughout New Zealand forests. This small fern reaches about 30 centimetres in height, with narrow sickle-shaped fronds that grow in tight clumps. The fronds are coloured dark green, fading to brown as they age. A distinctive midrib runs the length of each frond, providing structural support. Petako. The Māori name refers to this common spleenwort. Early Māori likely encountered sickle spleenwort in damp forest gullies though its small size meant it was probably less significant than larger edible ferns. Settlers found the fern less palatable but recognised its value as ground cover in shady gardens. Today the species serves as an indicator of forest health. Its presence signals intact riparian zones and suitable moisture levels. The species inhabits damp shaded areas in native forests throughout New Zealand. It prefers moist fertile soils with high humidity, thriving where rainfall is consistent and drainage is good. Fronds are narrow and sickle-shaped, divided into many small leaflets that create a lacy appearance. Spores are produced on the underside of fertile fronds in continuous lines along the midrib. These spores are released into the air, drifting on wind currents until they land on suitable substrate. Diet consists of nutrients obtained through photosynthesis and absorption from soil via shallow root systems. The fern does not consume organic matter directly but rather extracts minerals and water from surrounding substrate. This autotrophic lifestyle allows it to thrive in nutrient-poor soils where other plants struggle. Classified as Not Threatened, sickle spleenwort remains widespread throughout New Zealand. Populations are stable in suitable forest habitat. However the species is sensitive to habitat disturbance. When forests are logged or modified, populations decline rapidly. Its presence signals intact mycorrhizal networks and healthy forest ecosystems. Conservation efforts focus on protecting remaining native forests from logging and development to maintain these critical underground connections.