• Ferns with large rhizomes covered in fleshy stipules
• Thick petioles bear large, bipinnate blades that are articulated by swollen bases
• Leaves are usually 5-6m long and 3m wide
• The pinnules are elliptic, with free venation and small dentation at the apex

Morphology

• Giant ferns to 7m tall
• Rhizomes massive, globose, erect, radially arranged, to 150cm tall and to 100cm wide
• Stipules 10cm wide when dry (to about 20 cm when fresh), densely long-scaly above, triangular-keeled, the edges irregularly erose
• Leaves bipinnate, up to 5-7m long, petiole up to 2m long, up to 6 cm wide, the swollen base to 15cm wide, without nodes
• Blades up to 4m long and up to 3m wide, deltoid-elliptic, bright green above, slightly glaucous or lighter green below, with up to 25 (sub-)alternating pinna pairs
• Pinnae with up to 50 pairs of (sub)alternating pinnules, the pinnules occasionally forked or with a minute basal lobe (up to 1cm long)
• Largest lateral pinnules linear to ovate-lanceolate, 7-13 times longer than wide, 9-17 x 0.9-1.8cm, 13-15 x 3-3.8cm in young plants, widest below or at the middle, apices acute to acuminate, bases obtuse-truncate (or cordate), margins entire with a serrulate apex
• Terminal pinnae linear to ovate-lanceolate, similar to the lateral, 8-13(-16) x 0.9-2(-4)cm, widest below the middle, margins serrulate at apex
• Veins variable, some simple, usually paired at base or forked occasionally twice forked, 8-16 veins per cm
• Sori in two-rowed clumps of 9-14, and these placed on the veins in a submarginal row; juveniles forming the first pair of pinnae when plant is 4cm tall, bipinnate leaves appear when the plants are larger than 40cm, only adult plants (> 3m long) make fertile leaves

Diagnostic description
Angiopteris is a complex genus and the differences between the species with giant rhizomes and bipinnate leaves are poorly understood, because herbarium material is always fragmentary.It is of intermediate size. A. lygodiifolia is much smaller (leaves to 3m) and A. teijsmanniana is much larger (leaves to 9m). A. fokiensis has warty petioles, and A. angustifolia has a different shape of the stipules.

Evolution
Angiopteris is sister to Marattia s.s, which forms a clade sister to Christensenia. These are sister to a clade uniting Eupodium and Ptisana.Within Angiopteris, A. evecta is not well-resolved in the latest phylogenies, but the A. evecta complex is sister to the subgenus Archangiopteris.

Size

• Giant ferns, with hemispherical rhizomes of 1m across and 1.5m tall
• Leaves huge, bipinnate, 6m long and 3m wide

Growth
Relatively fast growing.

Lifecycle
Ferns produce spores. These spores develop into a single celled, heart-shaped structure called the gametophyte.On the gametophyte the male and female cells are produced, and the males swim to the females when there is sufficient moisture surrounding the gametophyte. After fertilisation, the embryo grows out into a sporophyte, the plants that produces the spores, and that we know as a fern.

Life expectancy
Plants can be very old, but no exact data is available.The author knows of a plant that was planted c. 50 years ago and is still thriving well and growing vigorously.

Molecular biology
The starchy rhizomes are edible after long processing to remove toxins.It is also used to flavour rice and to produce an intoxicating alcoholic drink.

Reproduction
Sexual reproduction by spores or vegetative reproduction by proliferous buds on the rhizomes.

Dispersal
The spores are dispersed by wind (anemochorous).Stipules of the rhizomes have proliferous buds that can break off and produce new plants.

Angiopteris evecta the giant or king fern is one of the largest ferns on the planet, not in height, but certainly in the size of its leavesAngiopteris evecta is a giant, primeval-looking fern that produces massive, globular trunks and gigantic leaves.The giant fern is native to Indonesia, New Guinea, coastal northern Australia and the south and west Pacific Islands.Angiopteris evecta is found in terrestrial rainforests, clearings and along roadsides, also in ravines and on steep volcanic slopes, always growing in very rich soils.

Angiopteris evecta (G. Forst.) Hoffm.:
China (Asia)

United States

Origin: Exotic

Regularity: Regularly occurring

Currently: Unknown/Undetermined

Confidence: Confident

Distribution

• Indonesia
• New Guinea
• coastal northern Australia
• south and west Pacific Islands

Naturalised in:

• Hawaii
• Jamaica
• Costa Rica
• Cuba

Habitat
Terrestrial in rainforests, clearings and along roadsides, often also found in ravines and steep volcanic slopes, always on very rich soils.

Trophic strategy
On nutrient rich volcanic soils.

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 6
Species: 6
Species With Barcodes: 1

United States

Rounded National Status Rank: NNA - Not Applicable

Rounded Global Status Rank: G4 - Apparently Secure

Reasons: Native to Polynesia, Malaysia, and Hawaii.

Conservation status
Occurs in abundance in most places, although programmes are in action to protect the Australian populations.

Threats
Logging and forest fires in Australia, and overgrowing by Lantana and grazing by goats are a treat on some Pacific islands.

Trends
Population are mostly stable though declining in Australia and increasing in new habitats in Hawaii, Costa Rica and Jamaica where it is an invasive species.

Comments: Considered exotic in North America (23 Mar 94)