Taxonomic name: Angiopteris evecta (J.R. Forst.) Hoffmann
Synonyms: Polypodium evectum J.G. Forster
Common names: bersarm (Palauan), demarm (Palauan), dermarm (Palauan), fa'agase (Samoan), gase (Samoan), giant fern (English), gwaegwae (Kwara'ae), hulufe vai (Tongan), kalme (Kosrae), katar (Pohnpei), king's fern (English), la'au fau pale (Samoan), Madagascar tree fern (English), mong (Yapese), mongmong (Yapese), mule's foot (English), mule's-foot fern (English), nahe (Tahitian), nase (Samoan), ne'e (Maori), oli oli (Samoan), oriental vessel fern (English), paiued (Pohnpei), palatao (Niuean), payuit (Pohnpei), ponga (Tongan), umpai (Pohnpei)
Organism type: fern Angiopteris evecta is a fern native to Polynesia, Melanesia, Micronesia, Australia, and New Guinea that has established invasive populations in Hawaii, Costa Rica, and Jamaica. It is known to establish dense stands that displace and shade out native plants and reduce biodiversity in ecosystems. Description
Rhizome forming a massive, somewhat spherical trunk to ca 60-90 cm high and 45 cm diameter Stipes thick and fleshy, to ca 2 m long, the base swollen and bearing two flat, rounded, dark brown, leathery, stipule-like outgrowth ca 5-10 cm long. Lamina 2- to 4-pinnate, glabrous, very large and spreading, to over 7 m long and to ca 2.5 m broad, the pinnae ca 30 cm wide; ultimate segments shortly stalked, commonly (8-) 10-13 (-20) cm long, (0.8-) 1.5-2.5 (-4) cm wide, linear, the base unequally wedge-shaped to more or less Angiopteris evecta is a very large, tropical fern. Its bipinnate, glabrous fronds reach up to 7 m long, 3 m wide and sprout spirally. Pinnae are about 30 cm wide, unequally wedge-shaped to more or less rounded, especially on the basal side, with shallowly toothed margins, often with a long, narrow, acuminate, more deeply toothed apex. They are shortly stalked and arranged mostly alternate with basal pinnae sometimes subopposite or opposite. Pinnae bear many leaflets 150x25mm with sporangia clustered in short double-rows of three to seven with no covering. It has a massive, some-what spherical, dome-like rhizome 60-90 cm high and 45 cm in diameter. Stipes are thick and fleshy, 2 m long, with swollen bases and bear two flat, rounded dark brown, leathery, stipule-like outgrowths 5-10 cm long. These fleshy stipules have proliferous buds that can grow into new plants when the stipules break off and find suitable ground (PIER, 2008; Christenhusz & Toivonen, 2008; McCormack, 20007). Occurs in:
natural forests, ruderal/disturbed, wetlands Habitat description
Angiopteris evecta inhabits tropical environments. Its typical climate range was found to include an annual mean temperature 19-27 °C, annual precipitation 1,054–5,447 mm, and elevations 0–1,492 m. It is known to thrive in moist forest and rainforest at low to middle elevations and appears to naturalize freely in wet valleys. Juvenile plants thrive in both sunny and shady locations, allowing the species to spread in dark primary rainand cloud forest as well as in open secondary vegetation (Christenhusz & Toivonen, 2008; PIER, 2008). General impacts
Angiopteris evecta establishes dense stands that dramatically alter ecosystems by displacing and outshading native species. It has established abundant, invasive populations in Hawaii, Costa Rica, and Jamaica that threaten native plants as well as general biodiversity and may pose a serious threat to native plant diversity in the tropics. Angiopsteris evecta is thought especially problematic on islands that house many of endemics, have patchy, relatively disturbed forests (Christenhusz & Toivonen, 2008; Christenhusz, pers. comm., 2010). Uses
Angiopteris evecta is commonly cultivated worldwide as an ornamental fern. Also, its starchy rhizomes are sometimes eaten or used to perfume coconut oil (Christenhusz & Toivonen, 2008). Geographical range
Native range: Polynesia, Melanesia, Micronesia, Australia, and New Guinea
Known introduced range: Hawaii, Jamaica, Coasta Rica Introduction pathways to new locations
For ornamental purposes:
Landscape/fauna "improvement":
Local dispersal methods
For ornamental purposes (local):
Natural dispersal (local):
Wind dispersed: Management information
Preventative measures: The restriction of cultivation and trade of Angiopteris evecta is advised to discourage further potentially invasive introductions (Christenhusz & Toivonen, 2008). Reproduction
Angiopteris evecta can reproduce vegetatively or by producing spores. Vegetative reproduction occurs when fleshy stipules located at the base of each petiole produce proliferous buds that break off on suitable substrate and produce new plants. A. evecta is very long lived and this method enables to produces billions of propugules and form of dense stands that threaten native flora. A. evecta also reproduces sexually via an alteration of generations of gametophyte and sporophyte stages. Like other ferns, spores that are produced by the sporophyte, or fern, stage germinate and produce a prothallium, which is a short lived, heart shaped gametophyte that bears both sex organs the archegonium and antheridium. After gamete production and fertilization a sporophyte emerges. A. evecta takes many years before it is capable of producing spores. However, once it has it is typically becomes well established. Adult leaves are covered in thousands of sporangia, each of which produces 1,440 spores (Haupt, 1940; Christenhusz & Toivonen, 2008). Lifecycle stages
Angiopteris evecta is very long-lived. Like other pteridophytes, it experiences and alteration of generations of gametophyte and sporophyte stages for sexual reproduction. The sporophyte, or "fern" stage produces spores that germinate to produce a prothallium, the gametophyte that bears sex organs which then, in turn, produces a sporophyte (Haupt, 1940; Christenhusz & Toivonen, 2008)
Compiled by: National Biological Information Infrastructure (NBII) & IUCN/SSC Invasive Species Specialist Group (ISSG)
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Last Modified: Tuesday, March 02, 2010
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