Aristida echinata Henrard |
Derivation
Aristida L., Sp. Pl. 1: 82 (1753); from the Latin arista
(an awn).
echinata- Latin for spiny. Inflorescence a very condensed panicle and
the spikelets or auxillary structures are awned, the whole thereby resembling
a hedgehog.
Common synonyms
Aristida ramosa R.Br. var. scaberula Henrard
Habit
Perennial, tufted. Culms robust, 50120 cm tall. Mid-culm internodes smooth,
glabrous. Lateral branches branched. Leaf-sheaths antrorsely scabrous, glabrous
on surface. Ligule a fringe of hairs, 0.5 mm long. Collar glabrous or pubescent.
Leaf-blades straight, flat or conduplicate or involute or convolute, 612
cm long, 12.5 mm wide. Leaf-blade surface scabrous.
Inflorescence
Inflorescence compound, a panicle. Panicle contracted, linear, 515 cm
long, 0.82 cm wide. Primary panicle branches 0.51.5 cm long.
Spikelets
Spikelets solitary. Fertile spikelets 1-flowered, comprising 1 fertile floret,
without rhachilla extension, lanceolate, terete, 6.310 mm long, breaking
up at maturity. Spikelets disarticulating below each fertile floret. Floret
callus elongated, pubescent, acute.
Glumes
Glumes persistent, similar, thinner than fertile lemma. Lower glume lanceolate,
410 mm long, equalling upper glume, membranous, 1-keeled, 1-nerved. Lower
glume lateral nerves absent. Lower glume surface scabrous. Lower glume apex
acute or acuminate. Upper glume lanceolate, 410 mm long, 60100%
of length of adjacent fertile lemma, membranous, 1-keeled, 1-nerved. Upper glume
lateral nerves absent. Upper glume surface scabrous. Upper glume apex acute
or acuminate.
Florets
Fertile lemma lanceolate, subterete, 6.310 mm long, coriaceous, pallid
and light brown, mottled with last colour, 3-nerved. Lemma surface tuberculate
or muricate, rough above. Lemma margins convolute, covering most of palea. Lemma
apex acute, 3-awned. Median (principal) awn 1119 mm long, without a column,
persistent. Lateral lemma awns present, 1119 mm long, subequal to principal
or shorter than principal, 100% of length of principal. Palea 20% of
length of lemma, without keels. Anthers 3. Grain with adherent pericarp, grooved,
58 mm long. Embryo 2550% of length of grain. Hilum linear, 30%
of length of caryopsis.
Continental Distribution:
Australasia.
Australian Distribution:
Queensland, New South Wales.
Queensland: Darling Downs, Leichhardt, Maranoa, Moreton, Warrego, Mitchell, Gregory North. New South Wales: Central Coast, North-Western Slopes, Central-Western Slopes, South-Western Slopes, North-Western Plains, South-Western Plains, North Far Western Plains.
Classification. (GPWG
2001):
Aristidoideae
Notes
Native. Acacia, Callitris, blue-grass downs (Dichanthium
spp.), Eucalyptus, and mulga (Acacia aneura) communities on loams,
red earths and sands. Flowering and fruiting Aug.July. Aristida echinata
differs from Aristida ramosa by the tuberculate surface of the lemma.
It was formerly placed as a variety of Aristida ramosa (see comments
under that species).
Spikelet (line drawing)
© Queensland Herbarium
by Will Smith