Deina Alefeld; Nivieria Seringe; Zeia Lunell, nom. illeg. superfl.

Plants annual. Culms usually erect, rarely decumbent at base. Leaf sheath split almost to base; ligule membranous; auricles lanceolate; leaf blade usually flat. Spike linear, oblong, or ovate, distichous; rachis disarticulating or not. Spikelets 1 per node, sessile, with (2 or)3–9(–11) florets; apical floret usually sterile; rachilla without joints. Glumes ovate, oblong, or elliptic, ± leathery, 3–11(–13)-veined with 1 or 2 veins raised as keels, glabrous or hairy, smooth or very scabrous along keels, apex obliquely truncate, 1- or 2-toothed, larger tooth sometimes extending into longish awn. Lemma 7–11(–15)-veined, ± keeled, apex awned or awnless; callus very short, obtuse. Palea usually slightly shorter than lemma. Lodicules ciliate at margin. Caryopsis ovate or oblong, ± plump, deeply furrowed, apex ± hairy. x = 7.

The generic name "Gigachilon" (Seidl in Berchtold et al., Oekon.-Techn. Fl. Böhm. 1: 425. 1836) was merely cited in synonymy (of Triticum polonicum) and was therefore not validly published (Saint Louis Code, Art. 34.1(c)). Under Art. 43.1, combinations in "Gigachilon" published by Löve (Feddes Repert. 95: 496–498. 1984) were not validly published either.

An artificial hybrid between Aegilops tauschii (Triticum tauschii) (♀) and T. urartu Thumanjan ex Gandilyan (♂) was described as T. ×teres H. R. Jiang & X. X. Kong (Acta Bot. Boreal.-Occid. Sin. 6: 206. 1986); it is not treated in this account.

In addition, the following three species have been recorded as cultivated in China (FRPS 9(3): 48–51. 1987): Triticum carthlicum Nevski (as T. turgidum Linnaeus var. carthlicum (Nevski) Yan ex P. C. Kuo), T. dicoccoides (Körnicke) Schweinfurth (as T. turgidum var. dicoccoides (Körnicke) Bowden), and T. timopheevii (Zhukovsky) Zhukovsky.

About 25 species: distributed as cultivated plants almost throughout temperate regions of both hemispheres, also on tropical mountains; four species (all introduced) in China.