The fernwren was first described by the English zoologist and ornithologist Charles Walter De Vis in 1889, and grouped with the scrubwrens as Sericornis gutturalis.

[9] It is found in the Paluma Range, near Townsville, and from the Tully Gorge National Park northwards to Cape Tribulation.

[10] The fernwren forages in the moist leaf-litter amongst the ferns and dense shrubbery, particularly in shady gullies of highland rainforests.

[8] As it searches through the accumulated debris of the forest floor, it frequently bows its head and flicks its short tail.

[8][9] In the breeding season from July to January (mainly October and November),[12] the male and female fernwrens together construct a domed nest, often hidden beneath an overhanging bank, fallen log or in a small cave amid the ferns.

[7] The female lays a clutch of two eggs, which are glossy white, sometimes finely spotted chestnut and tan.