''Mankyua'' is a monotypic genus and fern in the

Ophioglossales Ophioglossaceae, the adder's-tongue family, is a small family of ferns. In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), it is the only family in the order Ophioglossales, which together with the Psilotales is placed in the sub ...

. Its only species, ''M. chejuense'', grows only on Jeju Island of

South Korea South Korea, officially the Republic of Korea (ROK), is a country in East Asia, constituting the southern part of the Korea, Korean Peninsula and sharing a Korean Demilitarized Zone, land border with North Korea. Its western border is formed ...

. 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 ''Helminthostachys'' is a fern genus in the Ophioglossaceae (Adder's tongue) family.details
Tropicos.org. Missouri Botanical Garden. ...

''. It may be a basal offshoot of the ophioglossoid clade ''sensu stricto''. The genus name of ''Mankyua'' is in honour of Man Kyu Pak (1906-1988), who was a South Korean researcher and botanist ( Pteridology). The genus was

circumscribed In geometry, the circumscribed circle or circumcircle of a polygon is a circle that passes through all the vertices of the polygon. The center of this circle is called the circumcenter and its radius is called the circumradius. Not every polyg ...

by Byung Yun Sun, Moon Hong Kim and Chul Hwan Kim in

Taxon In biology, a taxon (back-formation from ''taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular nam ...

vol.50 (Issue 4) on page 1020 in 2001.

References

Sun, B.-Y., M.H. Kim, C.H. Kim, and C.-W. Park. 2001. Mankyua (Ophioglossaceae): a new fern genus from Cheju Island, Korea. Taxon 50: 1019-1024.

Line Notes

{{Taxonbar, from1=Q4574005, from2=Q17264249 Ophioglossaceae Endemic flora of Korea Monotypic fern genera Ferns of Asia