Panicum obseptum Trin. Gram. Pan.149
(1826).
Classification. (GPWG 2001) : Subfamily
Panicoideae. Paniceae.
Type of Basionym or
Protologue Information: Australia, Port Jackson: Woolls (CGE holo).
Key references
(books and floras): [1878] G.Bentham, Flora Australiensis 7 (486),
[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
(317).
Illustrations:
[2008] S.W.L.Jacobs, R.D.B.Whalley & D.J.B.Wheeler, Grasses of New South
Wales, 4th edn (317).
Habit.
Perennial. Rhizomes absent. Culms decumbent, stature slender to delicate, 10–30
cm tall, compressible, 5–10 -noded. Mid-culm internodes glabrous. Mid-culm
nodes pubescent. Lateral branches sparsely branched. Leaf-sheaths glabrous on
surface or hairy. Leaf-sheath auricles absent. Ligule a fringed membrane or a
fringe of hairs, a ciliate membrane, 0.5–0.75 mm long. Leaf-blades linear, 1–10
cm long, 1.25–5 mm wide. Leaf-blade surface smooth, glabrous or indumented.
Inflorescence.
Inflorescence compound, a panicle. Panicle lanceolate, 1.5–6 cm long, evenly
furnished.
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, lanceolate or elliptic,
dorsally compressed, 2.7–3.25 mm long. Rhachilla internodes brief up to lowest
fertile floret.
Glumes. Glumes
thinner than fertile lemma. Lower glume oblong or ovate or oblate, membranous,
without keels, 0–1 -nerved. Lower glume apex muticous. Upper glume ovate,
2.7–3.2 mm long, membranous, without keels, 7–9 -nerved. Florets. Basal
sterile florets 1, barren, without significant palea. Lemma of lower sterile
floret 100 % of length of spikelet, membranous, 5–9 -nerved, muticous.
Fertile lemma 2.3–2.6
mm long, without keel. Lemma apex muticous. Anthers 3.
Continental
Distribution: Australasia.
Australian
Distribution: Queensland, New South Wales, Victoria.
Queensland:
Burnett, Darling Downs, Moreton. New South Wales: North Coast, Central
Coast, South Coast, Northern Tablelands, Southern Tablelands. Victoria:
Midlands.
Notes.
Diagnostic features include the decumbent perennial habit, the racemose primary
branches, the relatively short lower glume and the semi-aquatic growth habit.
The reduced form of the inflorescence is similar to many species of Urochloa.
Introduced to
Victoria. In tropical and subtropical rain forests, tropical and subtropical
wet sclerophyll forests, dry sclerophyll forests, and tropical and subtropical
sub-humid woodlands. Flowers mostly Oct.-May.
