''Geosiris'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

in the flowering plant family

Iridaceae Iridaceae is a family of plants in order Asparagales, taking its name from the irises, meaning rainbow, referring to its many colours. There are 66 accepted genera with a total of c. 2244 species worldwide (Christenhusz & Byng 2016). It include ...

, 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 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 found elsew ...

Madagascar Madagascar (; mg, Madagasikara, ), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasikara, links=no, ; french: République de Madagascar), is an island country in the Indian Ocean, approximately off the coast of East Africa ...

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

Mayotte Island Mayotte (; french: Mayotte, ; Shimaore: ''Maore'', ; Kibushi: ''Maori'', ), officially the Department of Mayotte (french: Département de Mayotte), is an overseas department and region and single territorial collectivity of France. It is loc ...

in the

Indian Ocean The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or ~19.8% of the water on Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia to the east. To the south it is bounded by th ...

northwest of

. In 2017, a third species was found in

Queensland ) , nickname = Sunshine State , image_map = Queensland in Australia.svg , map_caption = Location of Queensland in Australia , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , established_ ...

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

myco-heterotroph Myco-heterotrophy (from Ancient Greek, Greek μύκης , "fungus", ἕτερος ', "another", "different" and τροφή ', "nutrition") is a symbiosis, symbiotic relationship between certain kinds of plants and fungi, in which the plant gets a ...

lacking

chlorophyll Chlorophyll (also chlorophyl) 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 allow plants to a ...

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

Greek Greek may refer to: Greece 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 ...

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 shoots from its nodes. Rhizomes are also called creeping rootstalks or just rootstalks. Rhizomes develop from axillary buds and grow hori ...

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 {{Unreferenced, date=December 2009 ''Orchidales'' is an order of flowering plants. In taxonomical systems, this is a relatively recent name as early systems used descriptive botanical names for the order containing the orchids. The Bentham & H ...

, and this was adopted in the

Cronquist system The Cronquist system is a taxonomic classification system of flowering plants. It was developed by Arthur Cronquist in a series of monographs and texts, including ''The Evolution and Classification of Flowering Plants'' (1968; 2nd edition, 1988) a ...

, with a note that the family was closely related to

Burmanniaceae Burmanniaceae is a Family (biology), 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 m ...

. 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 disco ...

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