Acrostichum

Acrostichum is a genus of tropical and subtropical ferns in the family Pteridaceae. The genus contains about three to four species, with Acrostichum aureum and Acrostichum speciosum being the most widely distributed. Species of Acrostichum are commonly known as sword ferns, a reference to their long, sword‑shaped fronds that can reach several meters in length. The fronds arise from a creeping or upright rhizome and typically have a glossy, dark green surface when mature. Young fronds are pale green and display abundant indusia that cover the sori, a feature that contributes to the name Acrostichum, derived from Greek meaning “surface of the mass”.

Acrostichum species thrive in wetland habitats such as mangrove swamps, tidal marshes, and riverbanks where they contribute to the stabilization of soil and the provision of habitat for a variety of organisms. They are known to tolerate regular salt spray and fluctuating water levels, and some species can be found in intertidal zones up to 30 meters above sea level. The fronds of Acrostichum aureum are sometimes harvested for ornamental use and occasionally for Ayurvedic medicine, though scientific documentation of medicinal properties remains limited.

The conservation status of Acrostichum species varies by region. While Acrostichum aureum is listed as a species of least concern by the IUCN Red List, local populations can be threatened by coastal development, pollution, and climate‑related changes such as sea‑level rise. Conservation efforts focus on habitat protection and research into the ecological role of these ferns in mangrove and tidal wetland ecosystems.