Phragmites karka

Phragmites karka (Retz.) Trin. ex Steud.
Nom. Bot. ed. 2, 2: 324 (1841).

Classification. (GPWG 2001) : Subfamily
Arundinoideae. Tribe Arundineae.

Basionym and/or
Replacement Name:
 Arundo karka
Retz., Observ. Bot. 4: 21 (1786).

Type of Basionym or
Protologue Information
: India:, Koenig s.n. herb. Retzius (HT: LD).

Recent synonyms:
P. vallatoria auct.

Key references
(books and floras):
[1952] C.A.Gardner, Flora of Western Australia 1
Gramineae (133), [1980] M.Lazarides, Tropical Grasses S.E.Asia
(438), [2002] D.Sharp & B.K.Simon, AusGrass, Grasses of Australia,
[2006] J.Jessop, G.R.M.Dashorst, F.M.James, Grasses of South Australia
(311).

Illustrations:
[1952] C.A.Gardner, Flora of Western Australia 1 Gramineae (132,
Pl. 39), [2006] J.Jessop, G.R.M.Dashorst, F.M.James, Grasses of South
Australia
 (311, fig. 243).

Habit.
Perennial. Rhizomes present, elongated. Basal leaf sheaths absent. Culms erect,
stature reed-like, 100–1000 cm tall. Leaves cauline. Ligule a fringed membrane,
a ciliate membrane. Leaf-blades 20–80 cm long, 10–40 mm wide. Leaf-blade surface
scaberulous.

Inflorescence.
Inflorescence compound, a panicle. Panicle oblong, dense, 30–50 cm long, 10–20
cm wide.

Spikelets.
Spikelets pedicelled. Fertile spikelets many flowered, with at least 2 fertile
florets (3–11), comprising 1 basal sterile florets, comprising 3–11 fertile
floret(s), with diminished florets at the apex, cuneate, laterally compressed,
9–14 mm long.

Glumes. Glumes
similar, similar to fertile lemma in texture. Lower glume elliptic, membranous,
without keels, 3–5 -nerved. Upper glume elliptic, 4–6 mm long, membranous,
without keels, 3–5 -nerved. Florets. Basal sterile florets 1, male or
barren, with palea. Lemma of lower sterile floret 100 % of length of spikelet,
membranous, 3–7 -nerved.

Fertile
lemma 8.5–11 mm long, without keel, 1–3 -nerved. Lemma surface glabrous. Lemma
apex muticous. Palea 2 -nerved. Lodicules present. Anthers 3 (2 in sterile
floret). Grain 1.1 mm long.

Continental
Distribution
: Africa, Temperate Asia, Tropical Asia, Australasia, and
Pacific.

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

Western Australia:
Gardner, Fitzgerald, Dampier. Fortescue. Northern Territory: Darwin
& Gulf. South Australia: Lake Eyre. Queensland: Burke, Cook,
South Kennedy, North Kennedy.

Notes.
This species is separated from P. mauritianus by only the shape of the
upper glume, and that they possibly do not deserve specific rank (W.D. Clayton,
Flora of East Tropical Africa 1: 120 (1970). P. karka sometimes
has pungent leaves, which provide an additional way of separating the species.

Common
aquatic reed, growing with the rhizomes in water.

 

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