Ischaemum triticeum

Ischaemum triticeum R. Br. Prodr. 205

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

Basionym and/or
Replacement Name:
Steud., Syn. Pl. Glumac. 1: 376 (1854).

Type of Basionym or
Protologue Information
: T: Shoalwater
Bay, Qld, 22 Oct. 1802, R.Brown
Iter Australiense 6153; holo: BM (photo BRI, K); iso: K (photo BRI).

Key references (books
and floras):
[1810]. R.Brown, Prodromus (205), [1878] G.Bentham, Flora
7 (519), [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 Wales

[2008] S.W.L.Jacobs, R.D.B.Whalley & D.J.B.Wheeler, Grasses of New South
, 4th edn (285).

Habit. Annual
or perennial. Culms sprawling, 50–200 cm tall. Mid-culm nodes glabrous or
bearded. Lateral branches simple or branched. Leaf-sheaths hairy. Ligule an
eciliate membrane, 1–3.5 mm long. Leaf-blades linear or lanceolate, 6–33 cm
long, 3–12 mm wide.

Inflorescence digitate, with ramose branches. Rhachis fragile at the nodes.

Spikelets sessile, 1 in the cluster. Companion spikelets pedicelled, 1 in the
cluster. Companion spikelets represented by single glumes or developed,
comprising 2 subequal glumes without lemmas or male, 3.5–10 mm long. 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, oblong or ovate, dorsally compressed, 6–10 mm long.

Glumes. Glumes
dissimilar, firmer than fertile lemma, shiny. Lower glume oblong, cartilaginous
or coriaceous, keeled, 2-keeled, winged on keel, winged broadly or narrowly,
5–7 -nerved. Upper glume lanceolate, 6–7 mm long, coriaceous, keeled, 1-keeled,
winged on keel, 5–9 -nerved. Upper glume surface glabrous. Upper glume apex
awned. Florets. Basal sterile florets 1, male, with palea. Lemma of
lower sterile floret hyaline or membranous, 7 -nerved.

Fertile lemma 3–4 mm
long, without keel, 5 -nerved. Lemma apex dentate, awned, 1 -awned. Median
(principal) awn from a sinus, 8–18 mm long overall, with a twisted column. Anthers

: Australasia.

: Queensland, New South Wales.

Cook, Moreton, Port Curtis, Wide
Bay, South Kennedy. New South Wales: North Coast.

Notes. Occurs
on sandy foredunes of northern N.S.W. and southern Qld. and one specimen from
Lizard Is. Flowers July--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