Slender, erect, annual, to 9 cm high, sparsely hairy to glabrous; stems often branching from base. Leaf-lamina reniform, discolorous, 2–10 mm across, shallowly 3–5-lobed or lobed to c. midway; lobes entire or 3-toothed, each tooth with an often caducous bristle at apex; petiole 1–10 mm long; stipules scarious, fringed, white. Umbels simple, leaf-opposed, 2–3 mm diam., 3–15-flowered; peduncle 2–10 mm long; pedicels 0.5–1.5 mm long. Petals white to purple. Fruits 0.5–1 mm long and wide, smooth, dark; mericarps with keeled dorsal rib, intermediate ribs prominent but not keeled, bordering a narrow pouch toward the junction of the 2 mericarps. Flowers Sep.–Nov.
LoM, Wim, GleP, VVP, VRiv, GipP, OtP, WaP, Gold, CVU, GGr, DunT, NIS, EGL, EGU, WPro, HSF, HNF, OtR, VAlp. Also WA, SA, NSW, Tas. Widespread in woodlands, forests, heath, and cleared areas, often growing with H. foveolata (see notes under that species).
