family of ferns dating from the Mesozoic Era (roughly 250 million to 65 million years ago) and distinguished by an umbrella-shaped membranous covering over clusters (sori) of spore-bearing structures (sporangia). The leaves are fan-shaped and lobed in narrow segments or have long midribs that aid the plant in a climbing habit. The family now includes only two genera (Matonia, two species; and Phanerosorus, two species). Although once widespread in the tropics, the family's members now occur only in the Malayan region, mainly on open ridgetops at higher elevations, on mountain summits, and on limestone.