Zygochloa paradoxa

Zygochloa paradoxa (R.Br.) S.T.Blake. Univ.
Queensland
Dept. Biol. Pap
1 (19): 8 (1941).

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

Common name:
Sandhill Canegrass.

Basionym and/or
Replacement Name:
 Neurachne
paradoxa
R. Br., Exped. Centr. Austral. 2: App. 89 (1849).

Type of Basionym or
Protologue Information
: Australia:
Sturt .

Key references
(books and floras):
[1878] G.Bentham, Flora Australiensis 7 (504 as Spinifex
paradoxus
), [1981] M.Lazarides in J.Jessop (ed)., Flora of Central
Australia
(483), [2002] D.Sharp & B.K.Simon, AusGrass, Grasses of
Australia
, [2006] J.Jessop, G.R.M.Dashorst, F.M.James, Grasses of South
Australia
(497), [2008] S.W.L.Jacobs, R.D.B.Walley & D.J.B.Wheeler, Grasses
of New South Wales
(403).

Illustrations:
[2006] J.Jessop, G.R.M.Dashorst, F.M.James, Grasses of South Australia  (498, Fig. 428), [2008] S.W.L.Jacobs,
R.D.B.Whalley & D.J.B.Wheeler, Grasses of New South Wales, 4th edn
(403).

Derivation:
from the Greek para (irregular) and doxa (opinion). Different
from the expected in regard to related species.

Habit.
Perennial. Rhizomes present, elongated. Culms geniculately ascending, 40–150 cm
tall, 4–8 mm diam., woody. Lateral branches suffrutescent. Ligule a fringe of
hairs, 0.5–1.2 mm long. Leaf-blades 1–30 cm long, 1–10 mm wide.

Inflorescence.
Inflorescence compound, a panicle, with racemose branches.

Spikelets.
Spikelets sessile. Male spikelets sessile. 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, dorsally compressed, 5–10 mm long.

Glumes. Glumes
similar, thinner than fertile lemma. Lower glume ovate, chartaceous, without
keels, 7–9 -nerved. Lower glume surface indumented. Upper glume ovate, 5–10 mm
long, chartaceous, without keels, 7–9 -nerved. Upper glume surface glabrous or
indumented. Florets. Basal sterile florets 1, barren, with palea. Lemma
of lower sterile floret 100 % of length of spikelet, chartaceous, 5 -nerved.
Fertile florets female.

Fertile
lemma 4.5–10 mm long, 5 -nerved. Lemma surface glabrous. Anthers 3. Grain 3 mm
long.

Continental
Distribution
: Australasia.

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

Northern
Territory
: Central Australia North, Central
Australia South. South Australia:
Lake Eyre, Gairdner-Torrens Basin, Flinders
Ranges, Eastern, Eyre
Peninsula. Queensland:
Gregory North, Gregory South. New
South Wales
: North Far Western Plains, South Far
Western Plains.

Notes.
Disarticulation is primarily at the compacted culm nodes and secondarily at the
spikelet base. The disseminule consists of a spikelet, a very short pedicel,
and 3 highly modified bracts with pronounced curved wings. These unusual
modifications undoubtedly assist in dispersal.

 Spikelets of the male inflorescence occur in a
reduced panicle and the prolonged rachis, bract and prophyllum are not modified
into winged structures.

In shrub steppe
shrublands, arid tussock grasslands, and arid hummock grasslands. Flowers mostly
Mar.-Sept.

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