T: [Cape Provinces, Swartkops River] Zwartkops Rivier, K.L.P.Zeyher 103; syn: B [destroyed after having been selected as type by R.S.Adamson, J. Linn. Soc. Bot. 50: 15 (1935)], BOL; Worcester, Waterfall, C.F.Ecklon & K.L.P.Zeyher [as Juncus punctorius 1. 11] p.p.; syn: B [destroyed], PRE; Zondagsrivier bei Graaff-Reinet [Sundays River at Graaff-Reinet], H.Bolus 188; syn: BOL; .Camdeboosberg, 4.5000 Fuss., J.F.Drège [Juncus oxycarpus .c.]; syn: W [only!].
Perennials, usually 30–55 cm tall, caespitose; rhizome short, horizontal, with abbreviated internodes. Cataphylls 1–2, brownish; basal leaf usually single or absent; Cauline leaves 2–3 (–4), terete, unitubular, distinctly septate, c. 5–16 cm long, 1.2–3.5 mm in diam.; auricles obtuse to rounded, 1–3 mm long, usually yellowish. Lower bract sheath-like, with blade short, 0.5–3 cm long. Inflorescence rich, decompound, much-branched, of (5–) 10 to many obconical to semiglobose, (2–) 3–7 (–15)-flowered heads 5–9 mm wide; capitulum bracts ovate, acute, scarious, brownish at base. Tepals ±equal, 2.4–3.5 mm long; outer tepals lanceolate-carinate, with a green and veined central band, dark castaneous-brown in upper part; inner tepals broadly lanceolate, acute to mucronate, with broad distinct membranous margins. Stamens (3–) 6; anthers 0.4–0.8 mm long; filaments 0.5–0.7 mm long; style c. 0.2 mm long; stigma reddish, 1.0–1.5 mm long. Capsule unilocular, narrowly trigonous-prismatic or oblong-trigonous, gradually narrowing in c. 0.3–0.5 mm rostrum, 2.8–3.8 mm long, castaneous-brown to dark brown, shining, much exceeding perianth. Seeds ellipsoid-ovoid, c. 0.5–0.6 × 0.2–0.3 mm, apiculate, pale brown, c. 15–20-striate longitudinally, transversely reticulate; appendages absent.