Common name
Common Native Couch
Spider Grass
False Couch
Kimberley Couch

Derivation
Brachyachne (Benth.) Stapf, in D.Prain (ed.), Fl. Trop. Africa 9: 20 (1917) in clavis; from the Greek brachys (short) and achne (scale, chaff), alluding to lemmas shorter than glumes.

convergens- from the Latin convergo (approach). Spikelets two-ranked but appearing to be one-ranked.

Published in
Hooker's Icon. Pl. t. 3099: (1922).

Habit
Annual or perennial, tufted, short-lived. Stolons absent or present. Basal leaf sheaths glabrous. Culms erect or geniculately ascending or decumbent, 20–60 cm tall. Ligule a fringed membrane, 0.5 mm long. Leaf-blades 3–6 cm long, 2–3 mm wide. Leaf-blade surface glabrous or pilose. Leaf-blade apex obtuse or acute.

Inflorescence
Inflorescence digitate, with spicate branches. Spikes 2–4, unilateral, 2–7 cm long. Rhachis flattened, scabrous on margins. Spikelet packing broadside to rhachis, imbricate, regular, 2-rowed.

Spikelets
Spikelets appressed, solitary. Fertile spikelets 1-flowered, comprising 1 fertile floret, without rhachilla extension, lanceolate or oblong, laterally compressed, compressed strongly, 3–5 mm long, breaking up at maturity. Spikelets disarticulating below each fertile floret.

Glumes
Glumes deciduous, similar, with lower wider than upper, firmer than fertile lemma, parallel to lemmas. Lower glume oblong, 3–5 mm long, 100% length of upper glume, coriaceous, 1-keeled, winged on keel, winged broadly, 1-nerved, midnerve scaberulous or scabrous. Lower glume lateral nerves absent. Lower glume apex obtuse or acuminate. Upper glume oblong, 3–5 mm long, 150–250% of length of adjacent fertile lemma, coriaceous, 1-keeled, winged on keel, winged all along, 1-nerved, midnerve scaberulous or scabrous. Upper glume lateral nerves absent. Upper glume apex obtuse or acuminate.

Florets
Fertile lemma ovate, laterally compressed, 2.2–2.8 mm long, membranous, 3-nerved. Lemma midnerve ciliate. Lemma margins ciliate. Lemma apex obtuse, muticous or mucronate. Palea 2-nerved. Palea keels ciliate. Grain with adherent pericarp, ellipsoid or ovoid or obovoid, laterally compressed, 1.7–2 mm long. Embryo 50% of length of grain.

Continental Distribution:
Australasia.

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

Western Australia: Gardner, Fitzgerald, Hall, Dampier, Fortescue. Northern Territory: Darwin & Gulf, Victoria River, Barkly Tableland, Central Australia North. Queensland: Cook, Burke, North Kennedy, South Kennedy, Port Curtis, Leichhardt, Darling Downs, Gregory North, Mitchell, Warrego, Maranoa. New South Wales: Central Coast, North-Western Plains.

Classification. (GPWG 2001):
Chloridoideae: Cynodonteae

Notes
Endemic; occurs in summer rainfall area across the continent N of the Tropic of Capricorn, excluding desert areas of the N.T. and W.A., and S central Qld, with a few records from northern N.S.W. and the central E coast; recorded from a range of habitats including claypans, river banks, levees and floodplains, irrigated cotton fields, gorges and sandplains, often in disturbed areas such as roadsides; usually common or dominant in the understorey where it occurs.
Considered good dry season fodder in northern Australia.

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