Aristida annua B.K.Simon. Austrobaileya
2: 87 (1984).
Classification. (GPWG 2001) : Subfamily
Aristidoideae. Aristideae.
Type of Basionym or
Protologue Information: Australia: Queensland: Leichardt Dist.: Gindie via
Springsure, 29 Mar 1958, P. J. Skerman s.n. (HT: BRI-11772).
Key references
(books and floras): [2002] D.Sharp & B.K.Simon, AusGrass, Grasses of
Australia.
Illustrations:
[2005] K.Mallet (ed.), Flora of Australia 44B: Poaceae 3 (Fig.
20A-C).
Derivation: L.
annual. Annuals.
Habit. Annual.
Culms 25–50 cm tall, 2–3 -noded. Mid-culm internodes glabrous. Lateral branches
sparsely branched or branched. Ligule a fringe of hairs, 1 mm long. Leaf-blades
straight, flat or conduplicate or involute or convolute, 7–15 cm long, 1–1.5 mm
wide. Leaf-blade surface indumented.
Inflorescence.
Inflorescence compound, a panicle. Panicle elliptic, effuse, 10–20 cm long,
5–12 cm wide.
Spikelets.
Spikelets pedicelled. Fertile spikelets 1-flowered, comprising 1 fertile
floret(s), without rachilla extension, lanceolate, terete, 7–8.5 mm long.
Glumes. Glumes
similar, thinner than fertile lemma. Lower glume lanceolate, membranous,
keeled, 1-keeled, 1 -nerved. Lower glume apex awned. Upper glume lanceolate,
7–8.5 mm long, membranous, keeled, 1-keeled, 1 -nerved. Upper glume surface
asperulous or scabrous. Upper glume apex entire, awned.
Florets.
Fertile lemma 5.5–6.5 mm long, without keel, 3 -nerved. Lemma apex awned, 3
-awned. Median (principal) awn without a column. Lateral lemma awns present.
Palea without keels. Anthers 3. Grain 10.5 mm long.
Continental
Distribution: Australasia.
Australian
Distribution: Queensland.
Queensland:
Leichhardt.
Notes.
A. annua is distinctive in that it is the only annual species with a
convolute lemma and an open panicle.
Restricted
to a small area of central Queensland. Black earth and basalt soils. Flowering
and fruiting March, May to June.
