Cenchrus robustus

Cenchrus robustus R.D. Webster. Austral.Paniceae 27(1987).

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

Type of Basionym or
Protologue Information
: T: Queensland, Kaban via Ravenshoe, [June 1950] G.R.Walsh
s.n.
(BRI, holo).

Key references
(books and floras):
[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
(181).

Illustrations:
[2008] S.W.L.Jacobs, R.D.B.Whalley & D.J.B.Wheeler, Grasses of New South
Wales
, 4th edn (181).

Habit.
Perennial. Rhizomes present, short. Stolons absent. Culms erect, 40–100 cm
tall, 10–20 -noded. Mid-culm nodes glabrous. Leaf-sheaths smooth, glabrous on
surface. Ligule a fringe of hairs, 1–1.5 mm long. Leaf-blades 6–22 cm long, 3–7
mm wide. Leaf-blade surface scabrous, glabrous.

Inflorescence.
Inflorescence solid, of only a few spikelets (spicate). Panicle linear, 4–8 cm
long. Racemes 4–8 cm long.

Spikelets.
Spikelets sessile, 1–2 in the cluster. Involucre composed of bristles, connate
into a disc below. 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,
dorsally compressed, 7.3–9 mm long.

Glumes. Glumes
thinner than fertile lemma. Lower glume ovate, hyaline or membranous, without
keels, (0–)1 -nerved. Upper glume ovate, 2.8–4.1 mm long, membranous, without
keels, 1–3 -nerved. Upper glume surface asperulous. Florets. Basal
sterile florets 1, barren, with palea. Lemma of lower sterile floret 100 % of
length of spikelet, membranous, 5 -nerved.

Fertile lemma 7.5–9 mm
long, without keel.

Continental
Distribution
: Australasia.

Australian
Distribution
: Queensland, New South Wales.

Queensland:
Cook, Burke, North Kennedy, Burnett, Wide Bay, Moreton.

Notes.
Cenchrus robustus is closely related to C. caliculatus however,
it has significantly larger burrs and spikelets. This species is only known
from few collections.

In tropical and
subtropical rain forests, tropical and subtropical wet sclerophyll forests, and
tropical and subtropical sub-humid woodlands. Flowers Feb.-Oct.

 


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