Uranthoecium truncatum (Maiden &
Betche) Stapf. Hooker's Icon. Pl. t.3073 (1916).
Classification. (GPWG 2001) : Subfamily Panicoideae. Paniceae.
Basionym and/or
Replacement Name: Rottboellia
truncata Maiden & Betche, Proc. Linn. Soc. New South Wales 21:
741, t. 69 (1906).
Type of Basionym or
Protologue Information: Australia, Yandama: Mullen (K iso).
Key references
(books and floras): [1981] M.Lazarides in J.Jessop (ed)., Flora of
Central Australia (483), [2002] D.Sharp & B.K.Simon, AusGrass,
Grasses of Australia, [2006] J.Jessop, G.R.M.Dashorst, F.M.James, Grasses
of South Australia (490), [2008] S.W.L.Jacobs, R.D.B.Walley &
D.J.B.Wheeler, Grasses of New South Wales (392).
Illustrations:
[2006] J.Jessop, G.R.M.Dashorst, F.M.James, Grasses of South Australia (491, Fig. 424), [2008] S.W.L.Jacobs,
R.D.B.Whalley & D.J.B.Wheeler, Grasses of New South Wales, 4th edn
(392).
Habit. Annual.
Culms 15–45 cm tall. Ligule a fringed membrane, a ciliate membrane, 1.1–1.5 mm
long. Leaf-blades 4–15 cm long, 2–5 mm wide.
Inflorescence.
Inflorescence solid, a raceme. Racemes appressed, oblong, 0.2–1.5 cm long,
bearing 2–4 fertile spikelets on each. Central inflorescence axis 3–15 cm long.
Spikelets.
Spikelets sessile. Fertile spikelets 2-flowered, the lower floret barren
(rarely male), the upper fertile, comprising 1 basal sterile florets,
comprising 1 fertile floret(s), without rachilla extension, lanceolate,
dorsally compressed, 8–11 mm long.
Glumes. Glumes
dissimilar, thinner than fertile lemma. Lower glume oblong, chartaceous, without
keels, 7 -nerved. Upper glume ovate, 4.5–5.5 mm long, chartaceous, keeled,
2-keeled, 7 -nerved. Florets. Basal sterile florets 1, barren, with
palea. Lemma of lower sterile floret 100 % of length of spikelet, coriaceous,
2-keeled (above), 7–9 -nerved.
Fertile lemma 4–7.3 mm
long, without keel, 5 -nerved. Palea 2 -nerved.
Continental
Distribution: Australasia.
Australian
Distribution: Northern Territory, South Australia, Queensland, New South
Wales.
Northern Territory:
Central Australia North. South Australia: Lake Eyre. Queensland:
Burke, Gregory North, Maranoa, Mitchell, Warrego. New South Wales:
North-Western Plains, North Far Western Plains.
Notes. Arid
regions of mainland states other than W.A. and Victoria. In arid and semi-arid
low woodlands, shrub steppe shrublands, acacia shrublands, arid tussock
grasslands, and arid hummock grasslands. Flowers Mar.-June.
