Aristida utilis F.M.Bailey. Queensland
Agric.J. 18: 340 (1907).
Classification. (GPWG 2001) : Subfamily
Aristidoideae. Aristideae.
Type of Basionym or
Protologue Information: HT: M. Webb s.n., May 1907, Australia:
Queensland: Cook District: near Cooktown (BRI; IT: K (photo, US-1447336),
US-1162453).
Recent synonyms:
Aristida streptachne Domin.
Key references
(books and floras): [1810]. R.Brown, Prodromus (174 as Streptachne
stipoides), [1878] G.Bentham, Flora Australiensis 7 (572 as Streptachne
stipoides), [2002] D.Sharp & B.K.Simon, AusGrass, Grasses of
Australia.
Illustrations:
[1983] J.C.Tothill & J.B.Hacker, Grasses of Southern Queensland
(104(4)).
Derivation: L.
useful.
Habit.
Perennial. Culms 53–130 cm tall. Mid-culm internodes pubescent. Mid-culm nodes
glabrous. Lateral branches simple or sparsely branched or branched.
Leaf-sheaths smooth or scaberulous, glabrous on surface. Ligule a fringe of
hairs, 0.3–0.5 mm long. Leaf-blades curled or flexuous, flat or conduplicate or
involute or convolute, 10–21 cm long, 1.5–2 mm wide. Leaf-blade surface smooth
or scaberulous, glabrous or indumented.
Inflorescence.
Inflorescence compound, a panicle. Panicle lanceolate, 15–48 cm long, 1–6 cm
wide.
Spikelets.
Spikelets pedicelled. Fertile spikelets 1-flowered, comprising 1 fertile
floret(s), without rachilla extension, lanceolate, laterally compressed, 8–20
mm long.
Glumes.
Glumes similar, thinner than fertile lemma. Lower glume lanceolate, membranous,
keeled, 1-keeled, 3–5 -nerved. Lower glume surface glabrous. Lower glume apex
awned. Upper glume lanceolate, 8.3–17 mm long, membranous, keeled, 1-keeled, 1
-nerved. Upper glume surface glabrous. Upper glume apex entire, awned.
Florets.
Fertile lemma 8–20 mm long, without keel, 3 -nerved. Lemma surface glabrous or
indumented. Lemma apex awned, 1–3 -awned. Median (principal) awn 14–40 mm long
overall, with a twisted column. Column 5–9 mm long. Lateral lemma awns absent
or present. Palea without keels. Anthers 3.
Continental
Distribution: Australasia.
Australian
Distribution: Northern Territory, Queensland.
Northern Territory:
Darwin & Gulf. Queensland: Cook, North Kennedy, Port Curtis,
Burnett.
Infra -specific
taxa: var. utilis, var. grandiglumis.
Lemma to 12 mm long;
glumes to 12 mm long A. utilis var. utilis
Lemma more than 17 mm
long; glumes more than 15 mm long A. utilis var. grandiflora
