One of the ferns, Hymenophyllum whitei, was first recorded by botanist Cyril Tenison White in 1937 on Thornton Peak, one of Queensland’s highest points, located in the Daintree rainforest. Since then, despite repeated searches, researchers didn’t find the fern — that is, until a group of botanists set out on yet another plant survey in August 2017.
During this expedition, on the way to Thornton Peak, the researchers from the Royal Botanic Garden Sydney finally spotted H. whitei peeking out from a boulder on the side of the track, according to a new study.
“At first we struggled to convince ourselves that ‘this was it,’ but upon closer examination, we knew it couldn’t be anything else, so we allowed ourselves to get completely ecstatic about it,” Matt Renner, a co-author of the study and one of the botanists on the expedition, said in a statement.
In dry weather, the small fern completely desiccates and shrivels up, retracting into the surrounding flora like mosses, the researchers write, until it’s nearly undetectable. When moisture is available again, the fern re-expands. “This may in part explain the long period between collections of this species,” the researchers add.
Renner and his colleagues say that because H. whitei occurs in a very limited area and is found only within Daintree National Park, the species should be listed as endangered in Queensland.
Like H. whitei, the fern Oreogrammitis leonardii was previously known from a single collection by Australian-American naturalist Leonard John Brass in 1948, from a yet another remote summit, Mount Finnigan in northeastern Queensland.
Nearly 70 years later, during the 2017 survey, Renner and his colleagues found the fern again, growing on a tree trunk close to the ground, surrounded by the leafy liverwort Acroscyphella phoenicorhiza.
“We made some collections of ferns from a tree trunk that fit the description, but it wasn’t until we were back in Cairns that Dr. Barbara Parris, who described the species, confirmed we had rediscovered Oreogrammitis leonardii,” Renner said.
For O. leonardii, too, the researchers recommended a conservation status of endangered, “because of its limited distribution and the small area of potential high-elevation forested habitat around the summit complex of Mount Finnigan.”