Thinopyrum* Taxon 29: 351 (1980).
Derivation:. From Greek this (beach) and pyros (wheat), as it grows on beach dunes.
Key references (keys and floras):. C.A.Gardner, Flora of Western Australia 1 Gramineae 195 (1952) as Agropyron; B.K.Simon, Key to Australian Grasses 130 (1993) as Lophopyrum and 169 (1993); E.Edgar and H.E.Connor, Flora of New Zealand 5: 415–416 (2000); D.Sharp and B.K.Simon, AusGrass (2002); J.P.Jessop, Grasses of South Australia 275–279 (2006); S.W.L.Jacobs, R.D.B.Whalley & D.J.B.Wheeler, Grasses of New South Wales, 4th ed, 384–385 (2008); A.Wilson (ed.), Flora of Australia 44A: Poaceae 2: 102–104 (2009).
W.D.Clayton & S.A.Renvoize, Genera Graminum (1986), genus (syn. of elymus).
Naturalised. 5 species, from coasts of Europe. 3 species in Australia, SA, NSW, Vic, and Tas. Also New Zealand.
Habit. Rigid, erect, glaucous perennial, rhizomatous. Leaf blades narrow. Ligule an unfringed membrane.
Inflorescence. Inflorescence a single spike (the spikelets usually appressed and broad side facing rachis). Spikelet-bearing axes disarticulating at joints (the spikelets falling with the internode below).
Spikelets. Spikelets laterally compressed, solitary, sessile to subsessile; with naked rachilla extension. Fertile spikelets laterally compressed, falling with glumes.
Glumes. Glumes more or less equal (subequal), shorter than spikelet, shorter than adjacent lemmas, blunt or incised, awnless, non-keeled, similar. Lower glume 4–12 nerved. Upper glume 4–12 nerved.
Florets. Fertile florets 2–10. Lemmas similar in texture to glumes (leathery), entire at apex, blunt, muticous, without a germination flap, 5 nerved, with nerves confluent towards tip, not keeled (except towards the tip). Palea relatively long, 2 nerved, 2 keeled. Distal incomplete florets underdeveloped. Callus short (glabrous), pointed. Lodicules 2. Stamens 3. Stigmas 2. Grain medium sized to large, longitudinally grooved, compressed dorsiventrally, with hairs confined to a terminal tuft. Hilum long-linear. Embryo small. Endosperm hard.
Kranz Anatomy. C3.
2n = 14, 28, and 42, 2, 4, and 6 ploid, commonly adventive.
Habitat. Xerophytic. Coastal sands. Species of open habitats.
Classification. Pooideae; Triticeae.
Types Species. T. junceum (L.) Á.Löve.
Biogeographic Element. Clifford & Simon 1981, Simon & Jacobs 1990: Naturalised.