Chrysopogon elongatus

Chrysopogon elongatus (R.Br.) Benth. Fl. Austral. 7: 538 (1878).

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

Basionym and/or Replacement Name:  Holcus elongatus R. Br., Prodromus Florae Novae Hollandiae 1: 200 (1810).

Type of Basionym or Protologue Information: HT: R. Brown 6193, Australia (BM (photo, BRI, K); IT: K (photo, BRI), MEL (photo, BRI)).

Recent synonyms: Vetiveria elongata.

Key references (books and floras): [1810]. R.Brown, Prodromus (200 as Holcus elongatus), [1878] G.Bentham, Flora Australiensis 7 (538), [2002] D.Sharp & B.K.Simon, AusGrass, Grasses of Australia.

Habit. Perennial. Rhizomes present, short. Culms erect, 150–250 cm tall, 7 -noded. Ligule a fringe of hairs. Leaf-blades conduplicate, 25–50 cm long, 4–8 mm wide. Leaf-blade surface indumented.

Inflorescence. Inflorescence compound, a panicle of rames. Panicle lanceolate, 15–30 cm long, 2–3 cm wide. Rhachis fragile at the nodes.

Spikelets. Spikelets sessile, 1 in the cluster. Companion spikelets pedicelled, 1 in the cluster. Companion spikelets developed, male, 5.5–6.5 mm long. Companion spikelet glumes muticous. 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, linear or lanceolate, laterally compressed, 5–7 mm long.

Glumes. Glumes dissimilar, firmer than fertile lemma. Lower glume lanceolate, coriaceous, without keels, 5–8 -nerved. Lower glume apex muticous. Upper glume lanceolate, coriaceous, keeled, 1-keeled. Upper glume apex muticous or mucronate. Florets. Basal sterile florets 1, barren, without significant palea. Lemma of lower sterile floret 100 % of length of spikelet, hyaline, 2 -nerved.

Fertile lemma 4–6 mm long, without keel, 3 -nerved. Lemma apex dentate, awned, 1 -awned. Median (principal) awn from a sinus, 4–7 mm long overall, with a straight or slightly twisted column. Palea 0 -nerved, without keels. Anthers 3.

Continental Distribution: Tropical Asia and Australasia.

Australian Distribution: Northern Territory, Queensland.

Northern Territory: Darwin & Gulf. Queensland: Burke, Cook.

Notes. Creek banks and flood flats of areas round the Gulf of Carpentaria and coastal regions north of Cairns. Flowers Apr.--Sept. & Dec.--Jan.

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