Mankyua chejuensis

Also known as mankyua

Mankyua is a monotypic genus and fern in the Ophioglossales. Its only species, M. chejuense, grows only on Jeju Island of South Korea. While this plant is clearly ophioglossoid in the broad sense, its precise cladistic position is uncertain. It has a fused sporangial structure similar to Ophioglossum, but a vegetative structure, with palmately-radiating pinnae, reminiscent of Helminthostachys. It may be a basal offshoot of the ophioglossoid clade sensu stricto.