For fern lovers, the Potato fern (Ptisanaoreades) is a fern worth visiting the Wet Tropics for. Like the famed King Fern (Angiopteris evecta), the potato fern is a terrestrial fern that loves being close to streams and creeks, and is readily recognized by the large two-times pinnate fronds.
Historically, the genus Ptisana was considered to be part of the genus Marattia, and indeed, this species was previously known as Marattia oreades. However, after more detailed molecular and morphological phylogenetic analyses, Murdock (2008) split Marattia into three genera: Ptisana, comprising the old world tropical (and Australian) species, Eupodium (3–4 species) and in a more narrowly circumscribed Marattia (the latter 2 genera distributed in the American tropics.
In terms of morphological characters, Ptisana is distinguished easily from the King Fern (Angiopteris evecta) by its much smaller size, and also differences in the spore bearing structures.
iNaturalist entry:
https://www.inaturalist.org/observations/67293905
One easy place to see this fern is along the Mobo Creek Crater walk in Danbulla.
References
Murdock AG (2008) Phylogeny of marattioid ferns (Marattiaceae): Inferring a root in the absence of a closely related outgroup. American Journal of Botany 95(5): 626–641. https://doi.org/10.3732/ajb.2007308
Leaf Whispering in the Tropics 