Can anybody identify this fern? I found it in the mountains of central Thailand. It is epiphytic mostly, but also grows on the ground. It has tough leathery leaves and is from an area that has a long dry season.
It was very common in the area that I found it.
I believe that the species shown here are both of the genus Pyrrosia. Specific identification might be possible from the given photo but since frond division, a popular method for fern identification, isn't very possible with this genus, you might need to rely on the arrangement of sporangia, (which aren't present in this photo). Since there are about 100 species of Pyrrosia, positive specific identification might require a Pteridologist.
Some species to consider for the longer fronded specimen could include Pyrrosia lanceolata, Pyrrosia rasamalae, Pyrrosia rupestris and Pyrrosia adnascens.
For the ovate fronded specimen, perhaps Pyrrosia nummularifolia or Pyrrosia rupestris.
Pyrrosia Lingua (Shi Wei) is used in traditional Chinese medicine for several ailments: http://www.chineseherbshealing.com/pyrrosia-lingua/
The American Fern Society has published a comprehensive PDF on Pyrrosia which can be found here: http://amerfernsoc.org/ffa/Fiddlehead%20Forum/FF%20Volume%2035-36/Fiddlehead%20Forum%20Vol%2035%20No%202-3.pdf
