Apostasioideae

Apostasioid orchids
Apostasia wallichii
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Monocots
Order:	Asparagales
Family:	Orchidaceae
Subfamily:	Apostasioideae Horan. (1847)
Genera
Apostasia Neuwiedia
Distribution of Apostasioideae

In plant systematics Apostasioideae is one of the five subfamilies recognised within the orchid family, Orchidaceae. Only two genera, Neuwiedia and Apostasia, and 15 species, are recognised within the Apostasioideae in contrast to the other orchid subfamilies which are highly species rich.

The Apostasioideae are generally considered a basal lineage within the orchids^[1] based on molecular data and flower structure. All other orchid subfamilies with the exception of the Cypripedioideae are monandrous (possessing a single stamen), however Apostasioid orchids have 3 stamens.

As with all basal or 'primitive' groups, extant species within Apostasioideae do not represent direct ancestors of the other subfamilies, they simply share the same common ancestor. However, by having followed a separate evolutionary pathway from the other orchids extant Apostasioid orchids may allow us to make inferences about features present in that common ancestor.^[2]

References

1. ↑ Kocyan, A.; Qiu, Y.-L.; Endress, P.K. & Conti, E. (August 2004). "A phylogenetic analysis of Apostasioideae (Orchidaceae) based on ITS, trnL-F and matK sequences" (PDF). Plant Syst. Evol. 247 (3/4): 203–213. doi:10.1007/s00606-004-0133-3. Retrieved 2010-12-15 
2. ↑ Stern, W. L.; V. Cheadle; J. Thorsch (1993). "Apostasiads, systematic anatomy, and the origins of Orchidaceae". Botanical Journal of the Linnean Society. 111 (4): 411–445. doi:10.1111/j.1095-8339.1993.tb01913.x. 

Bibliography

• Pridgeon, A.M.; Cribb, P.J.; Chase, M.W. & F. N. Rasmussen (1999): Genera Orchidacearum Vol.1, Oxford U. Press. ISBN 0-19-850513-2

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