Iris acutiloba is a species in the genus Iris, it is also in the subgenus of Iris and section Oncocyclus. It is a rhizomatous perennial, from the mountains of the Caucasus and found in Turkey, Armenia, Azerbaijan, Turkmenistan, Dagestan in the North Caucasus, and Iran. It is a dwarf species, with narrow, falcate or curved leaves, it has one flower in spring or early summer, that comes in shades from cream, creamy white, whitish, pale brown, light grey, to pale violet. It is heavily veined or streaked and pointed, with 2 dark spots and brown, purple, dark purple, or black short beard. It is cultivated as an ornamental plant in temperate regions. There are two subspecies, Iris acutiloba subsp. lineolata and Iris acutiloba subsp. longitepala.
Description
It has a small, thick and compressed rhizomes, which have many branches, and gives the plant a creeping habit, across the surface of the ground, while being heated by the sun. The creeping habit creates clumps.
It has narrow, slender, curved, or falcate (sickle-shaped), leaves, that are glaucous, grey green, or medium green. They can grow up to between long, and between 0.2 and 0.6 cm wide.
It is dwarf species, and has a slender stem or peduncle, that can grow up to between tall.
The stem has lanceolate, slightly pinkish, or green, and membranous, spathes (leaves of the flower bud), they are long.
The stems hold 1, terminal, (top of stem) flower, blooming in spring, or early summer, between March (in Russia), April, or May. The leaves begin to grow in the late autumn and stop in the summer.
In his book 'Iris', Fritz Kohlein, wrote "the blossoms of this small plant render a sombre, bat-like effect."
The flower is in diameter, come in shades from cream, creamy white, whitish, pale brown, light grey, to pale violet, They are streaked, or heavily veined with brown, brown black, grey, purple, or purple-brown,
Like other irises, 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 reflexed, pointed, or lanceolate, they can be up to long. They are generally marked with 2, large dark red-brown, blackish, purple-violet, or dark purplish-brown spots, or deep purple signal patch. One spot is in the centre and the other is at the apex. In the middle of the falls, is a sparse, row of short hairs called the 'beard', which is brown, purple, dark purple, or black. The acute, pointed, standards are larger than the falls, they can be up to long, and unspotted.
In the wild, it is more variable in colour and flower form.
It has greenish, style branch that is , and has brown spots. It also has a cylindric ovary, green filaments and anthers It has long, perianth tube, that is cylindric and green dotted with purple.
After the iris has flowered, it produces a seed capsule, that contains large, white and yellow seeds.
Research
In 2015, a study was carried out on 8 species of iris found in Iran including Iris reticulata, Iris pseudocaucasica, Iris persica, Iris acutiloba and Iris meda. It found that the petals contain anthocyanins, (which are common floral pigments that form blue, purple and red colours).
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 1928 by Delaunay, in 1932 by Simonet, in 1969 by Zakharyeva & Makushenko, in 1975 by Gustafsson & Wendelbo and in 1980 by Awishai & Zohary. It is normally published as 2n=20.
Taxonomy
It is known in Russia as Ostrodolny Iris. Meaning 'sharp-lobed iris'.
The Latin specific epithet acutiloba is derived from two Latin words 'acutus' meaning acute or narrow and 'loba' meaning lobes or lobed. This is due to the narrow, pointed segments of the flower.
It was first published and described by Carl Anton von Meyer in Verz. Pfl. Casp. Meer. (sometimes known as Verz. Pfl, Cauc.) Vol.32 in Nov–Dec 1831.
It was also published in 'Gartenflora' Vol.13 page 323 in 1874, (with a colour illustration) and in The Gardeners' Chronicle 3rd Series Vol.94 on page 451 on 16 December 1932.
It has 2 known subspecies, Iris acutiloba subsp. lineolata and Iris acutiloba subsp. longitepala. Due to the classification of the subspecies, some authors have renamed the species as Iris acutiloba subsp. acutiloba Mathew & Wendelbo. Although many botanists in Russia and Turkey still classify Iris lineolata as a separate species.
It is listed in the 'Encyclopedia of Life, and in the Catalogue of Life as Iris acutiloba subsp. acutiloba.