Aristida macroclada

Aristida macroclada Henrard. Meded.
Rijks. Herb. Leiden
54A: 325 (1927).

Classification. (GPWG 2001) : Subfamily
Aristidoideae. Aristideae.

Type of Basionym or
Protologue Information
: HT: J. E. Tennison Woods & M. Holtze 12,
1886, Australia: Northern Territory:
Darwin and Gulf Region (K; IT: BRI (fragm., photo ex K), MEL).

Recent synonyms:
Arisrida novaeguineae Ohwi.

Key references
(books and floras):
[1969] E.E.Henty, Manual Grasses New Guinea
(29), [2002] D.Sharp & B.K.Simon, AusGrass, Grasses of Australia.

[2005] K.Mallet (ed.), Flora of Australia 44B: Poaceae 3
(Fig. 16B-C, as var. queenslandica).

Derivation: Gk.
makros, large; klados, stem. Panicle branches long and slender.

Perennial. Culms 60–100 cm tall, 5–9 -noded. Mid-culm internodes glabrous.
Lateral branches sparsely branched. Leaf-sheaths glabrous on surface. Ligule a
fringe of hairs, 0.3–0.5 mm long. Leaf-blades straight, flat or conduplicate or
involute or convolute, 15–30 cm long, 1–2.3 mm wide. Leaf-blade surface
glabrous or indumented.

Inflorescence compound, a panicle. Panicle elliptic, 17–24 cm long, 3–7 cm

Spikelets pedicelled. Fertile spikelets 1-flowered, comprising 1 fertile
floret(s), without rachilla extension, lanceolate, terete, 6–15 mm long.

Glumes. Glumes
similar, thinner than fertile lemma. Lower glume lanceolate, membranous,
keeled, 1-keeled, 1 -nerved. Lower glume apex mucronate. Upper glume
lanceolate, 6–15 mm long, membranous, keeled, 1-keeled, 1 -nerved. Upper glume
apex entire or erose, mucronate.

Fertile lemma 5.5–9.5 mm long, without keel, 3 -nerved. Lemma apex awned, 3
-awned. Median (principal) awn 11–37 mm long overall, with a straight or
slightly twisted column or with a twisted column. Column 1–8 mm long. Lateral
lemma awns present. Palea without keels. Anthers 3. Grain 5–8 mm long.

: Tropical Asia and Australasia.

: Northern Territory, Queensland.

Northern Territory: Darwin &
Gulf. Queensland:
Cook, North Kennedy.

Notes. A.
differs from A. psammophila and A. longicollis by
the inflorescence being loose to open and the branches being naked at the base.
It exists as two subspecies, one with a very short column and the other with a
fairly well developed column.

Infra -specific taxa:
subsp. macroclada, subsp. queenslandica.

Column of many spirals             A. macroclada subsp. queenslandica

Column of 1/2–1 spiral              A. macroclada subsp. macroclada

AVH 2011

Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith