Gaudinia* Ess. Agrostogr. 21, t. 6, fig. 6 (1812).
Derivation:. Named after J.F.A.P. Gaudin (1776–1833), Swiss clergyman and honorary professor of botany at Lausanne.
Key references (keys and floras):. B.K.Simon, Key to Australian Grasses 122 (1993); D.I.Morris, Student's Flora of Tasmania 4B: 238–239 (1994); D.Sharp and B.K.Simon, AusGrass (2002); J.P.Jessop, Grasses of South Australia 222–224 (2006); A.Wilson (ed.), Flora of Australia 44A: Poaceae 2: 156 (2009).
W.D.Clayton & S.A.Renvoize, Genera Graminum (1986), genus (174).
Naturalised. 4 species, from Mediterranean, Azores. 1 species in Australia, Vic and Tas.
Habit. Biennial or annual, tufted. Leaf blades narrow. Ligule an unfringed membrane.
Inflorescence. Inflorescence a single spike. Spikelet-bearing axes when disarticulating, disarticulating at joints (above the insertions of the spikelets).
Spikelets. Spikelets all partially embedded in rachis, laterally compressed, solitary (appressed to the concave rachis, edge-on), sessile; with naked rachilla extension. Fertile spikelets laterally compressed, disarticulating above glumes.
Glumes. Glumes unequal to more or less equal, shorter than spikelet to about equal to spikelet, (the longer) long relative to adjacent lemmas, pointed, awnless, non-keeled, similar. Lower glume 3–5 nerved. Upper glume 5–11 nerved.
Florets. Fertile florets 3–11. Lemmas similar in texture to glumes (leathery), entire at apex to incised (or bicuspid), awned or muticous (G. hispanica), 5 nerved or 7 nerved or 9 nerved, weakly 1 keeled. Awns 1, dorsal, geniculate. Palea relatively long, entire to apically notched, 2 nerved. Distal incomplete florets underdeveloped. Callus short, blunt. Lodicules 2. Ovary hairy. Stamens 3. Stigmas 2. Grain with hairs confined to a terminal tuft. Hilum short (round). Embryo small. Endosperm liquid.
Kranz Anatomy. C3.
2n = 14 (and 14+1), 2 ploid, commonly adventive.
Habitat. Mesophytic to xerophytic. Weedy places. Species of open habitats.
Classification. Pooideae; Poeae.
Notes. The genus has an unusual inflorescence for Aveneae, but the geniculate awn and compound starch grains exclude it from Triticeae (Clayton and Renvoize, 1986).
Types Species. G. fragilis (L.) P.Beauv.
Biogeographic Element. Clifford & Simon 1981, Simon & Jacobs 1990: Naturalised.