Asplenium australasicum
Bird's Nest Fern
Bird's Nest Fern
Wikipedia links: Monilophytes > Polypodiales > Aspleniineae > Aspleniaceae > Asplenium australasicum
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Common name: Bird's Nest Fern
Conservation status: . . .
Etymology:
From New Latin asplenium (“the spleenworts”), from its use to cure anthrax in livestock
Australasicum means of or from Australasia and New Zealand
Flowers:
The spores form in parallel lines which run in parallel with the veins and oblique to the midrib
Fruit:
The spores run in parallel to the veins and oblique to the midrib
Leaves:
It has a rosette of yellow-green fronds which are 60 to 80 cm long and 3 to 21 cm
There is a prominent midrib under its fronds, giving them a keeled appearance
It can be distinguished from A. nidus by its prominent midrib under its fronds, giving the fronds a keeled appearance
The clumps can reach a large size, with the centre of the fern acting as a reservoir for debris
Stem & branches:
Roots:
Habit:
It is an epiphytic Australasian fern
It grows as shrubby plant, with a rosette of fronds
It grows on rocks or as an epiphyte on trees
Habitat:
Distribution:
Native to eastern NSW and Queensland
Additional notes:
The colonial botanist William Woolls wrote "... as a caution to fern gatherers, sometimes a species of black snake coils itself up in the centre"
Taxonomy
It was originally described by English botanist John Smith in 1857 as Neottopteris australasica
He had reclassified the already known A. nidus in its own genus Neottopteris
Other botanists reclassified the genus as a section, Thamnopteris, within the genus Asplenium, and William Jackson Hooker gave it its current binomial name in 1859.
Although the section Thamnopteris is distinctive, defining the species has been difficult as the morphology of the plants is so simple
It has been confused with (and called) A. nidus,[and Japanese populations which were considered to be A. australasicum by their morphology have been found to be genetically distinct and reclassified as a new species, A. setori
A global phylogeny of Asplenium published in 2020 divided the genus into eleven clades, which were given informal names pending further taxonomic study. A. australasicum belongs to the "Neottopteris clade", members of which generally have somewhat leathery leaf tissue
While the subclades of this group are poorly resolved, several of them share a characteristic "bird's-nest fern" morphology with entire leaves and fused veins near the margin
Both the 2020 study[8] and a 2015 molecular study found that A. australasicum is polyphyletic, meaning that some populations were not closely related to others—A. australasicum from Fiji and Vanauatu were not closely related to A. australasicum from Australia and New Caledonia. Hence a revision with sampling of the species across its range was required to delineate the taxon and identify cryptic species
It forms a clade with the morphologically similar A. nidus sensu lato, but other bird's-nest ferns such as A. antiquum and A. phyllitidis form a separate subclade which is not particularly closely related
Uses
Apart from its use as an ornamental plant, bird's nest fern is also a popular vegetable in Taiwan, particularly in the Eastern part of the island where the young emerging fronds are used as a leafy vegetable, from both wild and cultivated plants
The fronds are now also gaining in popularity elsewhere because of the pleasant texture and taste
Cultivation
Its specimens were taken from logged areas, which helped them become popular in horticulture
It adapts readily to cultivation, as long as it has good drainage
Poor drainage renders it vulnerable to rotting
It can be grown in a tub or barrel
In cultivation it is occasionally attacked by white coconut scale on the underside of the fronds
Sources of information: