[5] The rhizomes grow level with the surface of the soil, so that they can benefit from heat from the sun.

[8] The leaves of the iris are falcate (sickle-shaped),[5] or erect,[4][6][7] or ensiform (sword-shaped).

[11] The iris can have up to 5–8 leaves,[4] which are greyish-green[5][8] or pale green and slightly glaucescent.

[9] The stem has pale green, ventricose (swollen or inflated) spathes (leaves of the flower bud), which are 9–10 cm (3.5–3.9 in) long.

[9] The single terminal (top of stem) flowers[15] bloom in late March[8][9] or April.

[5][12][14] In the middle of the falls, extending from the claw (the narrow section of petal near the stem),[9] there is a row of short hairs (velvet-like,[9]) called the 'beard', which is brown-black,[9] light brown,[5] or yellow,[7] tipped with brown.

[21] It has style arms which are 5 cm (2 in) long,[9] greenish yellow and spotted with purple,[4] a white anthers,[9] oblong-shaped ovary, short filaments,[9] and a 5 cm (2 in) long cylindrical green perianth tube.

[8] A study in 2005 found that pollen is transferred between flowers by night-sheltering solitary male bees, which are the only known pollinators of the plants.

[21] As most irises are diploid, having two sets of chromosomes, this can be used to identify hybrids and classification of groupings.

[20] The karyotype was counted as 2n = 20[5][7][13] by Marc Simonet, then by Kushnir in 1947, then by Randolph and Mitra in 1958 and by Avishai and Zohary in 1980.

[29] Iris atrofusca was first published and described by John Gilbert Baker in Gardeners' Chronicle (Gard.

[25] It grows in the arid desert,[19] dry hills,[4][5] rocky/stony slopes,[7] loessial plains,[4][10] semi-steppe shrublands, or even agricultural fields.

[4] It is a rare and endangered species,[5][8] due to populations being threatened by over-grazing,[10] and human development including roads and settlements.

[7][12] It is listed in the Israeli Red Data Book (Shmida and Polak, 2008) as 'rare' in the Samarian Desert,[12] and also the northern Negev.

They can be grown in pots, especially in deep ones known as 'long toms', but they need re-potting every 2 years and also extra feeding.