''Geosiris'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

in the flowering plant family

Iridaceae Iridaceae () is a family of plants in order Asparagales, taking its name from the Iris (plant), irises. It has a nearly global distribution, with 69 accepted genera with a total of about 2500 species. It includes a number of economically importan ...

, first described in 1894. It was thought for many years to contain only one species, '' Geosiris aphylla'',

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

Madagascar Madagascar, officially the Republic of Madagascar, is an island country that includes the island of Madagascar and numerous smaller peripheral islands. Lying off the southeastern coast of Africa, it is the world's List of islands by area, f ...

. But then in 2010, a second species was described, '' Geosiris albiflora,'' from Mayotte Island in the

Indian Ocean The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or approximately 20% of the water area of Earth#Surface, Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia (continent), ...

northwest of

. In 2017, a third species was found in

Queensland Queensland ( , commonly abbreviated as Qld) is a States and territories of Australia, state in northeastern Australia, and is the second-largest and third-most populous state in Australia. It is bordered by the Northern Territory, South Austr ...

, Australia, '' Geosiris australiensis''. ''Geosiris aphylla'' is sometimes called the "earth-iris." It is a small myco-heterotroph lacking

chlorophyll Chlorophyll is any of several related green pigments found in cyanobacteria and in the chloroplasts of algae and plants. Its name is derived from the Greek words (, "pale green") and (, "leaf"). Chlorophyll allows plants to absorb energy ...

and obtaining its nutrients from fungi in the soil. The genus name is derived from the

Greek Greek may refer to: Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group *Greek language, a branch of the Indo-European language family **Proto-Greek language, the assumed last common ancestor of all kno ...

words ''geos'', meaning "earth", and ''iris'', referring to the Iris family of plants. Its

rhizome In botany and dendrology, a rhizome ( ) is a modified subterranean plant stem that sends out roots and Shoot (botany), shoots from its Node (botany), nodes. Rhizomes are also called creeping rootstalks or just rootstalks. Rhizomes develop from ...

s are slender and scaly, and stems are simple or branched. The leaves are alternate, but having no use, are reduced and scale-like. The flowers are light purple. In 1939, F. P. Jonker assigned ''Geosiris'' to its own family Geosiridaceae in Orchidales, and this was adopted in the

Cronquist system The Cronquist system is a list of systems of plant taxonomy, taxonomic classification system of angiosperms, flowering plants. It was developed by Arthur Cronquist in a series of monographs and texts, including ''The Evolution and Classification of ...

, with a note that the family was closely related to

Burmanniaceae Burmanniaceae is a family of flowering plants, consisting of 99 species of herbaceous plants in eight genera. Description These plants are annual or perennial herbs, with generally unbranched stems, some lacking leaves. Some members of this fam ...

. The

Angiosperm Phylogeny Group The Angiosperm Phylogeny Group (APG) is an informal international group of systematic botanists who collaborate to establish a consensus on the taxonomy of flowering plants (angiosperms) that reflects new knowledge about plant relationships disc ...

has since subsumed the family into Iridaceae; it is currently placed in the monotypic subfamily Geosiridoideae.

References

External links

Missouri Botanical Garden photo of ''Geosiris'' flowers

Iridaceae Iridaceae genera Parasitic plants Taxa named by Henri Ernest Baillon {{iridaceae-stub