Distichlis J. Phys. Chim. Hist. Nat. Arts 89: 104 (1819).
Derivation:. From the Greek distichos (in 2 rows), referring to the conspicuous 2 ranked arrangement of the spikelets.
Key references (keys and floras):. G.Bentham, Flora Australiensis 7: 637–638 (1878); M.Lazarides, Flora of Central Australia 431 (1981); J.P.Jessop, Flora of South Australia 4: 1889–1890 (1986); B.K.Simon, Key to Australian Grasses 104 (1993); S.W.L.Jacobs and K.L.McClay, Flora of New South Wales 4: 544 (1993); N.G.Walsh, Flora Victoria 2: 556–557 (1994); D.I.Morris, Student's Flora of Tasmania 4B: 323–324 (1994); D.Sharp and B.K.Simon, AusGrass (2002); K.Mallet (ed.), Flora of Australia 44B: Poaceae 3: 322–323 (2005); J.P.Jessop, Grasses of South Australia 353–355 (2006);S.W.L.Jacobs, R.D.B.Whalley & D.J.B.Wheeler, Grasses of New South Wales, 4th Ed, 223 (2008).
W.D.Clayton & S.A.Renvoize, Genera Graminum (1986), genus (318).
Native. About 6 species, from America and Australia. 1 species in Australia, WA, SA, NSW, Vic, and Tas.
Habit. Perennial, saltgrass, with thick, conspicuously distichous leaves. Leaf blades narrow. Ligule a fringed membrane to a fringe of hairs (?). Plants monoecious with all fertile spikelets unisexual (rarely) or dioecious.
Inflorescence. Inflorescence of spicate main branches (of short racemes on a central axis) or a single raceme or paniculate (or reduced), contracted.
Spikelets. Spikelets laterally compressed, solitary, pedicelled; with naked rachilla extension. Fertile spikelets laterally compressed, tardily disarticulating above glumes.
Glumes. Glumes unequal, shorter than spikelet, shorter than adjacent lemmas, pointed, awnless, similar (firm). Lower glume 1–5 nerved. Upper glume 4–9 nerved.
Florets. Fertile florets 3–20. Lemmas entire at apex, pointed, muticous, (3–)7–9(–11) nerved, 1 keeled to not keeled. Palea relatively long, leathery, 2 nerved, 2 keeled. Palea keels more or less winged. Lodicules 2. Stamens 0. Stigmas 2. Grain ellipsoid. Hilum short. Endosperm hard.
Kranz Anatomy. C4.
2n = 40 (D. stricta), 4 ploid.
Habitat. Seashores and deserts. Species of open habitats.
Classification. Chloridoideae; Cynodonteae.
Notes. Distichlis is phylogenetically linked (Peterson, 2000) in a clade that includes Allolepis, Uniola, Reederochloa, Jouvea and Monanthochloë, most of which are dioecious. Species show a biogeographically unique distribution, with 12 species in the New World and one in Australia (B.K.Simon).
Types Species. D. maritima Raf., nom.illeg..
Biogeographic Element. Clifford & Simon 1981, Simon & Jacobs 1990: America.