Oplismenus hirtellus
(L.) P.Beauv. Australian Basket-grassStoloniferous annual or perennial. Culms prostrate or weakly ascending to 40 cm high. Leaves glabrous or hairy; blades flat, narrowly ovate to linear, 1–8 cm long and 3–10 mm wide, smooth to slightly scabrous, margins often finely undulate; ligule 0.5–1 mm long. Inflorescence a linear panicle, 4–12 cm long, the primary branches often rather distant, 3–15 mm long. Spikelets subsessile, 2–3 mm long (excluding awns), solitary or in small clusters along primary branches, each subtended by a few stiff hairs; lower glume 3–5-nerved, usually hairy, ovate, 1–2 mm long, with an awn 2–10 mm long; upper glume usually slightly longer than first but with a shorter awn or unawned; lower lemma 5–7-nerved, elliptic, as long as the spikelet, usually sprinkled with a few hairs; palea of lower floret membranous, linear, from half to three-quarters as long as lemma; fertile lemma narrowly elliptic, dorsally rounded, slightly shorter than or subequal to spikelet, firm, pale, smooth, shining and glabrous; palea subequal to lemma. Flowers mainly Aug.–Mar.
VVP, GipP, EGL, EGU, WPro, HSF, HFE. Also NT, Qld, NSW. Tropical North and South America, West Indies. Occasional to locally common in moist, shaded, lowland sites supporting warm-temperate rainforest (`jungle') vegetation at and east from the Mitchell River Gorge near Glenaladale. Recent collections from the vicinity of the Yarra River near Yarra Glen and Christmas Hills area suggest naturalisation from cultivated sources - it is occasionally grown as an 'ornamental' native grass - but the existence of a pre-1900 specimen at Melbourne Herbarium labelled 'Yarra River, Coranderrk' suggests it may be native in this area, remote from its 'core' occurrence in the east. Alternatively, it may be a very early introduction.
The recognition of taxa similar to O. hirtellus, viz. O. aemulus and O. imbecillis, has been based on characters which are commonly at least as dependent upon environmental factors and maturity of the plant as genetic differences (e.g. leaf breadth/length ratios, lengths of panicle branches, degree of hairiness, etc.). The approach of Webster (1987) uniting O. aemulus and O. imbecilis within a broad concept of O. hirtellus appears to have greater utility and is here followed.
Walsh, N.G. (1994). Poaceae. In: Walsh, N.G.; Entwisle, T.J., Flora of Victoria Vol. 2, Ferns and Allied Plants, Conifers and Monocotyledons, pp. 356–627. Inkata Press, Melbourne.