Iris potaninii
Iris potaninii is a species in the genus "Iris", it is also in the subgenus of "Iris" and in the "Psammiris" section. It is a rhizomatous perennial, from Siberia in Russia, Mongolia and China. It is a dwarf plant, having either subterranean or very small stems, long thin leaves and yellow, or dark violet to purplish blue flowers. It is cultivated as an ornamental plant in temperate regions. Description. Similar in form to "Iris tigridia" (within "Pseudoregalia section") and "Iris bloudowii" (another "Psammiris section" iris), but differs from bloudowii, in having an ob-conical, not prostrate rhizome. It  differs from tigridia by having old leaf fibres on the rhizome. It also differs from "Iris tigridia" in leaf form, "Iris potaninii" has rounded ended leaves, which do not end in a point. It has thick, short and tough rhizomes. Under the rhizomes, are thick, fleshy and yellowish, secondary roots. also On top of the rhizome, are the curled, fibrous remains of last seasons leaves. It has linear basal (growing from the base) leaves, which are not pointed at the ends (or obtuse). They can grow up to between long and 0.2–0.4 cm wide, at blooming time. The leaves then  lengthen, and by the time the iris has seed capsules, they are between long and 0.3–0.4 cm wide. It is a dwarf plant, having either subterranean, or very small stems or pedicels. They can reach up to between long. The pedicel (or dwarf stem) has 2 narrow, lanceolate (or oblong-lanceolate,) and (scarious) membranous spathes or bracts (leaves of the flower bud). They are long and 0.6 cm wide. The stem (or pedicel) holds 1 terminal (top of stem) flower, between April to May (in Russia), or May to June. The flowers are in diameter, come in yellow, or dark  violet to purplish blue shades. It has 2 pairs of petals, 3 large sepals (outer petals), known as the 'falls' and 3 inner, smaller petals (or tepals), known as the 'standards'. The falls are obovate (in shape), with markings or veins around a central yellowish or whitish beard. They are long and 1.2–1.5 cm wide, and have curled up edges. The erect standards are oblanceolate, and are long and 0.8–1.0 cm wide. They also have curled up edges. It has a long perianth tube, which is thread-ilke. It also has 1.5 cm long stamens, purple anthers and a 0.7  cm long (spindle-shaped) ovary. It has a 2.8 cm long and 6mm wide style branch, which has a flat crest and toothed edges. After the iris has flowered, between June or July (in Russia), or between July and September, it produces an ellipsoid seed capsule. The capsule is long and between 1.3 and 1.5 cm wide, and has 6 longitudinal ribs and a short beak appendage (at the top). It dehisces (splits open) from the middle of the capsule. Inside the capsule are seeds which are 3 mm (in diameter), flattened globular, or pyriform (pear shaped), wrinkled, and  reddish brown in colour. Biochemistry. In 2002, a study was carried out on the rhizome of "Iris potaninii". It found several chemical compounds, including 2 new isoflavones, 6, 3', 4'-trimethoxy-7 and 8, 5'-trihydroxyisoflavone. In 2008, a study was carried out on the anatomical structure of the leaf and drought resistance of 4 different species of Iris ("Iris songarica", "Iris potaninii", "Iris loczyi" and "Iris lactea") from Qinghai, China. It showed that all the species were strongly adaptable to drought conditions. Genetics. In 2012, a genetic study was carried out on "Iris laevigata" and its from several closely related iris species , including "Iris ensata", "Iris setosa", "Iris halophila", "Iris scariosa", "Iris potaninii", "Iris tenuifolia", "Iris bloudowii", and "Iris sanguinea". As most irises are diploid, having two sets of chromosomes, this can be used to identify hybrids and classification of groupings. It was counted in 1984 by Doronkin, as 2n=22. It is normally published as 2n=22. Taxonomy. It has the common name of 'curl-sheath iris' (in China), or 'Potanin iris'. It is written as 卷鞘鸢尾 in Chinese script, and known as "juan qiào yuān wěi" in Pinyin in China. The Latin specific epithet "potaninii" refers to Grigory Potanin (a Russian ethnographer  and natural historian). It was found in western Kansu (Gansu) in 1876. It was first published and described by Maxim. in 'Bull. Acad. Imp. Sci. Saint-Pétersbourg' Vol.26 page528 in 1880. It was also published in 'Mélanges Biol. Bull. Phys.-Math. Acad. Imp. Sci. Saint-Pétersbourg' Vol.10 page724 in 1880. In 1980's, it was thought to be part of the 'Pseudoregelias section', but it is still within the Psammiris section, in most sources. It was verified by United States Department of Agriculture and the Agricultural Research Service on 4 April 2003 and then updated on 10 April 2012. "Iris potaninii  is an accepted name by the RHS. Distribution and habitat. Iris potaninii" is native to temperate areas of Asia. Range. It is found in the Russian Federation, within Siberia, in the states of Aga Buryat, Buryatia, Chita (including Dahuria (or Transbaikal),) and Gorno-Altai. It is also found in China, in the provinces of Gansu, Qinghai, Sichuan and Xizang. It is also though to be found in Mongolia, and Tibet. Habitat. It grows on the rocky, gravelly or stony slopes, on dry hillsides, of mountains. They can be found at an altitude of above sea level. Conservation. The iris is  listed as 'rare', in Red Data Book of the Altai region. One colony of the iris is protected within Daursky Nature Reserve (in Chita Oblast, Russia). Cultivation. hardy, soil, sun, moisture, situation, pests, planting It is hardy in Russia, surviving winter in St Petersburg without shelter. It is hardy in a sheltered place, in the UK. It prefers to grow in sunny positions, in well-drained soils. It has been tried in various botanical gardens within Russia, since 1992, in Barnaul, Chita and St. Petersburg. It could be grown within gardens, in a rock garden, or mixed borders. Uses. "Iris  potaninii" has been used in traditional Mongolian herbal medicine, in the treatment of various diseases, including bacterial infections, cancers and inflammations. Also, some benzoquinones have been isolated from Iris species rhizomes, and used as anti-cancer agents in modern Chinese medicines.