Axonopus compressus*

Axonopus compressus* (Sw.) Beauv. Ess. Agrostogr. 154 (1812).

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

Basionym and/or
Replacement Name:
Sw., Nova Genera et Species Plantarum seu Prodromus 24

Type of Basionym or
Protologue Information
: Jamaica:, Shakespear s.n. (HT: S?; IT: BM).

Key references
(books and floras):
[1952] C.A.Gardner, Flora of Western Australia 1
Gramineae (238), [1969] E.E.Henty, Manual Grasses New Guinea
(33), [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

Illustrations: [1952]
C.A.Gardner, Flora of Western Australia 1 Gramineae (239, Pl.
70), [1983] J.C.Tothill & J.B.Hacker, Grasses of Southern Queensland
(124), [2008] S.W.L.Jacobs, R.D.B.Whalley & D.J.B.Wheeler, Grasses of
New South Wales
, 4th edn (164).

Perennial. Stolons present. Culms decumbent, 15–60 cm tall. Mid-culm nodes
pubescent. Ligule a fringed membrane, a ciliolate membrane, 0.4–0.6 mm long.
Leaf-blades linear or lanceolate, flat or conduplicate, (1.5–)3–8(–250) cm
long, 3–12 mm wide.

Inflorescence digitate or subdigitate, with spicate branches. Racemes 2–5, 3–10
cm long. Central inflorescence axis 0–2 cm long.

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, lanceolate,
dorsally compressed, 2–2.8 mm long.

Glumes. Glumes
thinner than fertile lemma. Upper glume lanceolate or elliptic or oblong or
ovate, 2.1–2.8 mm long, membranous, without keels, 4–5 -nerved. Upper glume
surface glabrous or indumented. Florets. Basal sterile florets 1,
barren, without significant palea. Lemma of lower sterile floret 100 % of
length of spikelet, 4–5 -nerved.

Fertile lemma 1.5–2.4
mm long, without keel, 4 -nerved.

: Africa, Temperate Asia, Tropical Asia, Australasia, Pacific,
North America, and South America.

: Northern Territory, Queensland, New South Wales, Lord Howe,
Christmas Is.

Western Australia:
Drummond, Menzies, Warren. Queensland: Cook, Moreton, North Kennedy,
Port Curtis, South Kennedy, Wide Bay. New South Wales: Central Coast.

Notes. Axonopus
is morphologically and cytologically variable, and consequently
Black (1963) recognized 5 varieties. It is closely related to A. fissifolius,
another widespread weedy species. Diagnostic features of A. compressus
include the relatively short upper lemma and leaf shape.

Introduced. Native to
the tropics and subtropics of North America, but is now widespread throughout
the tropics of the world. In tropical heaths, tropical and subtropical rain
forests, tropical and subtropical wet sclerophyll forests, Brigalow forests,
and tropical and subtropical sub-humid woodlands. It is a weedy species but makes
a suitable lawn grass. Flowers Jan.-May.

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