Echinochloa crus-pavonis*

Echinochloa crus-pavonis* (Kunth) Schult. Mant. 2: 269 (1824).

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

Basionym and/or Replacement Name:  Oplismenus crus-pavonis Kunth,.

Type of Basionym or Protologue Information: HT: Humboldt & Bonpland s.n., Sep, Venezuela: Sucre: Cumaná, vicinity of Bordones (P (photo, US); IT: US (fragm.)). Crescit im apricis caldissimis Provinciae Cumanensis prope Bordones, floret Septembri, Humbodlt & Bonpland s.n..

Key references (books and floras): [1969] E.E.Henty, Manual Grasses New Guinea (81), [2002] D.Sharp & B.K.Simon, AusGrass, Grasses of Australia, [2006] J.Jessop, G.R.M.Dashorst, F.M.James, Grasses of South Australia (447), [2008] S.W.L.Jacobs, R.D.B.Walley & D.J.B.Wheeler, Grasses of New South Wales (226).

Illustrations: [2006] J.Jessop, G.R.M.Dashorst, F.M.James, Grasses of South Australia  (446, Fig. 378), [2008] S.W.L.Jacobs, R.D.B.Whalley & D.J.B.Wheeler, Grasses of New South Wales, 4th edn (226).

Habit. Annual or perennial. Rhizomes absent. Stolons absent. Culms erect or geniculately ascending or decumbent, stature robust to moderate, 50–200 cm tall, 4–7 -noded. Leaf-sheaths smooth. Ligule absent. Leaf-blades 12–60 cm long, 5–25 mm wide. Leaf-blade surface smooth.

Inflorescence. Inflorescence compound, a panicle of racemes. Racemes numerous, 3–15 cm long. Central inflorescence axis 10–30 cm long.

Spikelets. Spikelets sessile, 2–4 in the cluster. 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, 2–3(–3.5) mm long. Rhachilla internodes brief up to lowest fertile floret.

Glumes. Glumes dissimilar, thinner than fertile lemma. Lower glume ovate, hyaline or membranous, without keels, 3–5 -nerved. Lower glume surface indumented. Lower glume apex mucronate. Upper glume ovate, 2–3.5 mm long, membranous, without keels, 5 -nerved. Upper glume surface indumented. Upper glume apex muticous. Florets. Basal sterile florets 1, male or barren, with palea. Lemma of lower sterile floret 100 % of length of spikelet, membranous, 5 -nerved, awned.

Fertile lemma 2–3 mm long, without keel, 5 -nerved. Lemma apex mucronate. Anthers 3. Grain 1.5–2 mm long.

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

Australian Distribution: Western Australia, South Australia, Queensland, New South Wales.

Western Australia: Drummond. South Australia: Murray, Southern Lofty. Queensland: Wide Bay. New South Wales: North Coast, Central Coast, Central Tablelands.

Notes. Diagnostic features include the length of the upper floret and distinct secondary branching of the primary branches.

Introduced; W.A., S.A., Qld, and N.S.W. Geobotanical distribution: Dawson, Sturt, Merredin, and Eyre. Native to the tropics of Africa and the Americas. In tropical heaths, tropical and subtropical rain forests, dry sclerophyll forests, and temperate sub-humid woodlands. Rare in Australia and its status is uncertain. Flowers Feb.-Mar.

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