Common name
Dark Swamp Wallaby Grass

Derivation
Amphibromus Nees, Lond. J. Bot. 2: 420 (1843); from the Greek amphi (about, near) and bromos (food, the oat), rightly alluding to similarity with Avena (not Bromus).

recurvatus- Latin for reflexed. Spikelets with spreading or reflexed awns.

Published in
Amer. J. Bot. 18: 415 (1931).

Common synonyms
Helictotrichon recurvatum (Swallen) T.A.Cope & T.B.Ryves

Habit
Perennial, tufted. Basal leaf sheaths distinctly ribbed, glabrous or sparsely hairy. Culms erect, 80–150 cm tall, 1–1.5 mm diam., 3–5-noded. Mid-culm internodes terete or elliptical in section, ridged, smooth or scaberulous. Mid-culm nodes glabrous. Leaf-sheaths ribbed, smooth or scaberulous. Ligule an eciliate membrane, 4–11 mm long, acute. Leaf-blades flat or involute, 15–30 cm long, 2–3.5 mm wide. Leaf-blade surface ribbed, scabrous, glabrous.

Inflorescence
Inflorescence compound, a panicle. Panicle contracted, 10–30 cm long. Primary panicle branches appressed, 2–3-nate, 3–6 cm long. Panicle axis scabrous. Panicle branches hispid.

Spikelets
Spikelets solitary. Pedicels 5–10 mm long, glabrous or pubescent. Fertile spikelets many flowered, comprising 3–6 fertile florets, with a barren rhachilla extension or with diminished florets at the apex, oblong, laterally compressed, 7–11 mm long, breaking up at maturity. Spikelets disarticulating below each fertile floret.

Glumes
Glumes persistent, similar, thinner than fertile lemma. Lower glume lanceolate, 3.3–5.5 mm long, 80–100% of length of upper glume, membranous, much thinner above, much thinner on margins, 1-keeled, 1–3-nerved, midnerve scabrous. Lower glume lateral nerves absent or distinct. Lower glume apex acute or acuminate. Upper glume elliptic, 4–5.5 mm long, 100% of length of adjacent fertile lemma, membranous, much thinner above, with hyaline margins, 1-keeled, 3–5-nerved. Upper glume apex acute.

Florets
Fertile lemma elliptic, 4–5.5 mm long, cartilaginous, 5–7-nerved. Lemma surface hispid. Lemma apex dentate, 4-fid, with simple equal lobes or with outer lobes shorter, with lobes 0.43–1 mm long, 1-awned. Median (principal) awn dorsal, arising 50–66% way up back of lemma, geniculate, 9–18 mm long overall, 5–13 mm long, with a straight or slightly twisted column. Column 3.3–3.5 mm long, hirtellous. Palea 70–95% of length of lemma. Palea keels eciliate or ciliolate, adorned above. Palea apex obtuse. Apical sterile florets resembling fertile though underdeveloped. Lodicules 2, 0.8–1.3 mm long, membranous, smooth or ciliate, acute. Anthers 3, 1.2–2 mm long, eventually exserted. Ovary glabrous. Grain with adherent pericarp, 1.8–2.3 mm long, light brown, glabrous. Embryo 10–30% of length of grain. Hilum linear, 20–35% of length of caryopsis.

Continental Distribution:
Australasia.

Australian Distribution:
South Australia, Victoria, Tasmania.

South Australia: Kangaroo Island, South-eastern. Victoria: Wannon, Grampians, Victorian Volcanic Plain, Otway Plain, Gippsland Plains, East Gippsland. Tasmania: North West, North East, West Coast, Central Highlands, East Coast, South West, Mt Field.

Classification. (GPWG 2001):
Pooideae: Aveneae

Notes
Endemic. In wet areas such as lagoons and swamps swamps, from sea-level to about 1100 m. Flowers Nov.–Jan.

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