Paspalidium basicladum

Paspalidium basicladum D.K.Hughes. Bull.
Misc. Inform.
318 (1923).

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

Type of Basionym or
Protologue Information
: ST: Stoward 200, Australia: Western
Australia: Kiminoppin ST: Stoward 139, Australia: Transcontinental
Railway, east of Coolgardie ST: Drummond s.n., Australia.

Key references
(books and floras):
[1981] M.Lazarides in J.Jessop (ed)., Flora of
Central Australia
(478), [2002] D.Sharp & B.K.Simon, AusGrass,
Grasses of Australia
, [2006] J.Jessop, G.R.M.Dashorst, F.M.James, Grasses
of South Australia
(477 as Setaria).

Illustrations:
[2006] J.Jessop, G.R.M.Dashorst, F.M.James, Grasses of South Australia  (477, fig. 409 as Setaria).

Habit. Annual.
Rhizomes absent. Culms erect or geniculately ascending or decumbent, 20–70 cm
tall, 3–6 -noded. Mid-culm internodes hollow or spongy, glabrous. Mid-culm
nodes glabrous. Lateral branches sparsely branched. Leaf-sheaths glabrous on
surface. Ligule a fringed membrane or a fringe of hairs, 0.8–1.2 mm long.
Leaf-blades flat or conduplicate, (4.5–)6–12(–18) cm long, (2–)3(–6) mm wide.
Leaf-blade surface scabrous, glabrous.

Inflorescence.
Inflorescence compound, a panicle of racemes. Racemes appressed, 2–4.5 cm long,
1.5–2.5 mm wide, bearing 9–20 fertile spikelets on each. Central inflorescence
axis 8–20 cm long.

Spikelets.
Spikelets pedicelled. 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 oblong,
dorsally compressed, 2.5–3 mm long.

Glumes.
Glumes thinner than fertile lemma. Lower glume oblong, membranous, without
keels, 3(–5) -nerved. Lower glume surface glabrous. Lower glume apex muticous.
Upper glume elliptic, 2.3–2.8 mm long, membranous, without keels, 7 -nerved. Florets.
Basal sterile florets 1, barren, without significant palea. Lemma of lower
sterile floret 100 % of length of spikelet, membranous, 5–7 -nerved.

Fertile lemma 2.3–2.8
mm long, without keel. Lemma apex mucronate.

Continental
Distribution
: Australasia.

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

Western Australia:
Carnarvon, Austin. Northern Territory: Central Australia North, Central
Australia South. South Australia: North-western, Lake Eyre, Nullabor,
Gairdner-Torrens Basin, Flinders Ranges, Eastern, Eyre Peninsula, Northern
Lofty. Queensland: Burke, Gregory North.

Notes.
This species is closely related to P. clementii but generally differs in
larger vegetative parts and spikelet structures. It is also related to P.
gracile
but differs in the annual habit and lacks the very pronounced
constriction at the spikelet base. The lowermost primary branches are generally
well formed in P. basicladum whereas in P. gracile the lowermost
primary branch is typically a short cluster of spikelets.

In shrub steppe
shrublands, acacia shrublands, arid tussock grasslands, and arid hummock grasslands.
Flowers mostly Feb.-Aug.



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