Pentapogon quadrifidus (Labill.) Baill.
five-awned spear-grass
Erect annual or short-lived perennial tufts, 15-60 cm; branching extravaginal. Leaf-sheath rounded, membranous, light green to cream, or light brown with strong, paler ribs, ± glabrous and shining to densely pubescent, shredding into fibres at maturity. Ligule 0.3-0.6 mm, membranous, truncate, erose, abaxially ciliate. Leaf-blade 3-6 cm × 0.5-0.9 mm diam., strongly involute, ± densely pubescent, tip subacute. Culm erect, slender, nodes pubescent, internodes ± villous especially near nodes. Panicle 4-8 cm, rather dense to ± lax, shortly and narrowly branched; rachis glabrous to pubescent, branches pubescent. Spikelets 1-flowered, 12-20 mm, light greenish brown to purplish; disarticulation above glumes; rachilla very shortly prolonged. Glumes subequal, 1-3-nerved, submembranous, acute to shortly mucronate, keeled, keel scabrid; lower 1-nerved, upper 3-nerved. Lemma 3.2-4.5 mm, 5-nerved, chartaceous, firmer than glumes, tightly involute, finely, closely scabrid above, apex 2-lobed with stout geniculate awn from sinus and each lobe tipped by 2 short fine awns; central awn with twisted column 2-6 mm and inclined ± straight arista 6-12 mm, lateral awns straight, 2-7.5 mm. Palea hyaline, shorter and narrower than lemma, 2-keeled, keels short-ciliate near apex. Callus hair-fringed, hairs 1-1.3 mm. Lodicules 2, glabrous. Stamens 3; anthers 0.4-0.7 mm. Ovary glabrous, styles free. Caryopsis c. 2.3 × 0.5-0.8 mm; embryo small; hilum punctiform; endosperm liquid.
S.: Marlborough (Ure Valley), North Canterbury (Upper Glenmark), Otago (Waitati). In grassland.
Naturalised from Australia; south-eastern Australia and Tasmania.
In Victoria, Australia, "Wide variation exists in the dimensions of the panicle and the awns of the lemma, and the extremes appear vastly different, but these are linked by a complete range of intermediates." [Walsh, N. G. and Entwisle, T. J. (Eds) Fl. Victoria 2: 491 (1994)]. In Tasmania var. parviflorus (Benth.) D.I.Morris is recognised.
