Leptocarpus scariosus R.Br.

Herb, dioecious, caespitose, perennial, often forming large tussocks. Culms 80–120 cm long, stout, terete, 1.5–2.2 mm diam., smooth to minutely striate or pitted and occasionally with a longitudinal furrow, light-to grey-green and often purplish towards the base, with a covering of pale, closely appressed, scale-like trichomes. Sheaths 0.8–1.6 (–2.2) cm long, striate, pale-to dark-brown with a covering of pale, closely-appressed, scale-like trichomes; with an initially prominent but caducous, hyaline, membranous, apical margin to 5 mm wide; awn to 5 mm long. Inflorescence: male spikelets in a much-branched, terminal fascicle 5–15 cm long, the spikelets erect to drooping on filiform pedicels; female spikelets densely clustered in a narrow, interrupted, terminal fascicle 5–20 cm long. Male spikelets ovoid, 3.5–5 mm long; glumes c. 15, all fertile, ovate, acuminate to shortly aristate, 2.0–2.5 mm long (with a short awn up to 0.5 mm long), brown contrasting with pale hyaline margin, glabrous. Female spikelets narrow-to broad-ovoid, 5–8 mm long; glumes up to 5 sterile lower glumes and 4–14 fertile upper glumes, broad-ovate, 2–3 mm long, brown, aristate, with a distinct pale silvery hyaline margin c. 0.2 mm wide and an erect awn 0.4–2 mm long; floral bracts 1 or 2, keeled, narrow-lanceolate to linear, 1.0–1.5 mm long, brown-hyaline, membranous, sparsely pubescent. Male flowers: tepals 5, except the lowest flower in spikelet with 6 tepals, 1.0–1.5 mm long, brown-hyaline, membranous, glabrous; 2 outer tepals lanceolate, acuminate, keeled; inner tepals flat, narrow-ovate, acute; stamens 3, filaments very short, anthers 0.5–0.6 mm long. Female flowers: tepals 6, inner and outer tepals similar, linear, acute, weakly keeled, membranous, brown-hyaline, sparsely pubescent, 1.0–1.5 mm long; style 3-branched, shortly connate at the base, the free portion almost wholly stigmatic. Nut narrow-ellipsoid, c. 1–1.2 mm long, glossy pale-brown. Culm anatomy: chlorenchyma interrupted by groups of pillar cells that extend from the parenchyma sheath to the epidermis.

Seasonally wet swamps and stream banks on oligotrophic soils or sometimes in permanently wet sites; on sandy and peaty soils. In permanently wet sites sometimes germinating while submerged, as described for Meeboldina crassipes (Meney & Pate 1999, Pate & Meney 1999), which is included in (considered a synomym of) Leptocarpus scariosus.