Common name
Brown Beetle Grass
Small-flowered Beetle Grass

Derivation
Leptochloa P.Beauv., Ess. Agrostogr. 71 (1812); from the Greek leptos (slender) and chloa (a grass), referring to inflorescences.

fusca- Latin for dark or swarthy. Glumes or lemmas dark-brown.

Published in
Rev. Gram. 1: 91 (1829).

Common synonyms
Diplachne fusca (L.) P.Beauv. ex Roem. & Schult.
Diplachne muelleri Benth.
Diplachne parviflora (R.Br.) Benth.
Diplachne reptatrix (L.) Druce
Diplachne uninervia (J.Presl) Parodi
Leptochloa uninervia (J.Presl) Hitchc. & Chase
Leptochloa malabarica (L.) Veldkamp

Habit
Annual or perennial, tufted, persisting or short-lived. Basal leaf sheaths glabrous. Culms erect or geniculately ascending or decumbent, of moderate stature or slender, 25–150 cm tall, rooting from lower nodes. Ligule an eciliate membrane, 1.2–8 mm long, entire or lacerate, acute. Leaf-blades flat or conduplicate or involute or convolute, 14–55 cm long, 0.8–5 mm wide, rigid, mid-green or grey-green. Leaf-blade midrib widened. Leaf-blade surface scabrous. Leaf-blade apex attenuate.

Inflorescence
Inflorescence compound, a panicle of racemes. Racemes 10–30, erect or spreading, straight, unilateral, 2–15 cm long. Central inflorescence axis 7–40 cm long. Rhachis semiterete. Spikelet packing broadside to rhachis, imbricate or approximate or lax or distant.

Spikelets
Spikelets solitary. Pedicels filiform, 0.5–1.5 mm long. Fertile spikelets many flowered, comprising 6–11 fertile florets, with diminished florets at the apex, elliptic, laterally or slightly dorsally compressed, 5–18 mm long, breaking up at maturity. Spikelets disarticulating below each fertile floret. Rhachilla internodes eventually visible between lemmas. Floret callus evident, pubescent, obtuse, disarticulating obliquely.

Glumes
Glumes persistent, similar. Lower glume lanceolate, 0.9–4.6 mm long, 60–70% length of upper glume, membranous, 1-keeled, 1-nerved, midnerve scabrous. Lower glume lateral nerves absent. Lower glume apex acute or acuminate. Upper glume oblong, 1.8–7.4 mm long, 100–130% of length of adjacent fertile lemma, membranous, 1-keeled, 1-nerved, midnerve scabrous. Upper glume lateral nerves absent. Upper glume apex obtuse or acute, muticous or mucronate.

Florets
Fertile lemma elliptic or oblong, 1.8–6.1 mm long, membranous, dark green or grey, 3-nerved. Lemma midnerve ciliate, hairy below. Lemma lateral nerves close to margins. Lemma surface pubescent. Lemma margins pilose, hairy below. Lemma apex dentate, 2-fid, mucronate or 1-awned. Median (principal) awn from a sinus, 0.3–1.6 mm long overall. Palea lanceolate, 2-nerved. Palea keels scabrous. Palea surface pubescent, hairy on flanks. Palea apex acute. Apical sterile florets resembling fertile though underdeveloped. Lodicules 2, cuneate, fleshy. Anthers 3, 0.2–2.7 mm long. Grain with adherent pericarp, ellipsoid, dorsally compressed or flattened, biconvex or concavo-convex, 1.6–1.8 mm long.

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

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

Western Australia: Gardner, Hall, Dampier, Carnegie, Helms, Fortescue, Ashburton, Carnarvon, Austin, Avon. Northern Territory: Darwin & Gulf, Barkly Tableland, Central Australia North, Central Australia South. South Australia: North-western, Lake Eyre, Gairdner-Torrens Basin, Flinders Ranges, Eastern, Murray, Yorke Peninsula, Southern Lofty. Queensland: Cook, Burke, North Kennedy, South Kennedy, Port Curtis, Leichhardt, Burnett, Wide Bay, Darling Downs, Moreton, Gregory North, Gregory South, Mitchell, Warrego, Maranoa. New South Wales: North Coast, Central Coast, Central Tablelands, North-Western Slopes, Central-Western Slopes, South-Western Slopes, North-Western Plains, South-Western Plains, North Far Western Plains. Victoria: Murray Mallee, Riverina, Victorian Volcanic Plain. Tasmania: East Coast.

Classification. (GPWG 2001):
Chloridoideae

Notes
Native; all states; widespread and common in warm-temperate and tropical areas. Flowers usually after rain.

There are four subspecies, three in Australia.

Leptochloa fusca (L.) Kunth subsp. fusca
All states except Tasmania.

Leptochloa fusca (L.) Kunth subsp. muelleri (Benth.) N.Snow
All states except Victoria and Tasmania.

Leptochloa fusca (L.) Kunth subsp. uninervia (J.Presl) N.Snow
All states except Victoria.