Setaria surgens

Setaria surgens Stapf. Bull. Misc.
Inform.
265 (1909).

Classification. (GPWG 2001) : Subfamily
Panicoideae. Paniceae.

Type of Basionym or
Protologue Information
: HT: Versteeg 1907, 08 Nov 1907, Netherlands New Guinea (K; IT: BO, L).

Recent synonyms:
S. brownii.

Key references
(books and floras):
[1952] C.A.Gardner, Flora of Western Australia 1
Gramineae (266), [1981] M.Lazarides in J.Jessop (ed)., Flora of
Central Australia
(481), [2002] D.Sharp & B.K.Simon, AusGrass,
Grasses of Australia
, [2008] S.W.L.Jacobs, R.D.B.Walley &
D.J.B.Wheeler, Grasses of New South Wales (371).

Illustrations:
[2008] S.W.L.Jacobs, R.D.B.Whalley & D.J.B.Wheeler, Grasses of New South
Wales
, 4th edn (371).

Habit. Annual.
Rhizomes absent. Culms erect or geniculately ascending or decumbent, 20–60 cm
tall, 5–6 -noded. Mid-culm nodes glabrous. Lateral branches fastigiate. Ligule
a fringe of hairs. Leaf-blades flat or involute, 3.5–20 cm long, 1–5 mm wide.
Leaf-blade surface smooth or scabrous, glabrous or indumented.

Inflorescence.
Inflorescence solid, a panicle. Panicle linear, 2–5 cm long.

Spikelets.
Spikelets pedicelled, 1 in the cluster. Involucre composed of bristles, free
throughout. 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, elliptic or obovate, dorsally
compressed, 2.5–2.9 mm long.

Glumes. Glumes
thinner than fertile lemma. Lower glume ovate, membranous, without keels, 3–5
-nerved. Upper glume ovate, 1.6–2.5 mm long, membranous, without keels, 5
-nerved. Upper glume surface scabrous. Florets. Basal sterile florets 1,
barren, with palea. Lemma of lower sterile floret 100 % of length of spikelet,
membranous, 5 -nerved.

Fertile lemma 2.2–3 mm
long, without keel. Lemma apex mucronate. Anthers 3. Grain 1.5 mm long.

Continental
Distribution
: Tropical Asia and Australasia.

Australian
Distribution
: Western Australia, Northern Territory, Queensland,
New South Wales.

Western Australia: Gardner,
Fitzgerald, Hall, Dampier. Northern Territory:
Darwin & Gulf, Victoria River,
Barkly Tableland, Central Australia North. Queensland: Burke, Burnett, Cook, Darling Downs,
Gregory North, Leichhardt, Maranoa, Mitchell, Moreton, North Kennedy, Port
Curtis, South Kennedy, Warrego, Wide
Bay. New South Wales: North-Western
Plains.

Notes.
Setaria surgens resembles S. apiculata, but spikelet length
distinguishes them. In addition, S. surgens commonly has a relatively
longer lower glume and the rugosity is usually more pronounced. Setaria
apiculata
tends to inhabit more tropical areas.

In tropical and
subtropical sub-humid woodlands, acacia shrublands, and arid hummock
grasslands. Distributed in the arid areas of Australia. Flowers mostly
Jan.-July.

 

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