Lepidosperma is a genus of sedge-like perennial plants in the family Cyperaceae, order Poales, described by the French botanist Jacques Labillardière in his Novae Hollandiae Plantarum Specimen (1804). With approximately 70 species recognised worldwide — around 65 of them occurring in Australia, of which roughly 60 are endemic — it is one of the most species-rich sedge genera on the continent. Additional species are native to southern China, southeast Asia, New Guinea, New Caledonia, and New Zealand.
Plants are rhizomatous perennials that often form dense clumps. The culms are nodeless and vary considerably in cross-section: some species have terete culms, others are compressed, biconvex, 4-angled, or irregularly angular. Leaves are basal, with isobilateral, culm-like blades (occasionally reduced to sheathing scales) and a ligule is present. The inflorescence is panicle-like, simple or compound, with involucral bracts usually shorter than the inflorescence itself.
Spikelets are terete and typically contain a single bisexual flower (rarely two) together with one or more staminate flowers below it. Glumes number 4–8 and are spirally arranged, with the lower 2–4 empty and the uppermost usually reduced. The hypogynous scales — usually 6, rarely 3 — are basally inflated at maturity, often becoming bristle-like above, and fall together with the nut at dispersal. Stamens number 3. The style is 3-branched, persistent, and fused with the nut. The nut is trigonous to terete, typically smooth at maturity with 3 pale ribs running from the style base down the nut's sides.
Among the more distinctive members of the genus are L. forsythii, recognised by its very dark red-brown leaf sheaths and unusual complement of only 3 hypogynous scales plus swollen stamen filaments; L. quadrangulatum, with its strongly 4-angled culms; L. semiteres, bearing a single flat acute culm margin and spreading spikelets; and L. laterale, a widespread species with flat to concavo-convex culms and relatively long spikelets. L. viscidum is notable for culm margins that are viscid, scabrous, and often ciliate.
Etymology
The name Lepidosperma is a compound of the Greek lepis (scale) and sperma (seed), referring to the scale-like hypogynous structures that enclose and fall with the nut at maturity — a distinctive character of the genus. It was coined by Labillardière in 1804.
Distribution
Lepidosperma occurs primarily in Australia, where approximately 65 species are found across all states except the Northern Territory; around 60 of these are endemic. Outside Australia, the genus extends to southern China, southeast Asia, New Guinea, New Caledonia, and New Zealand.
Taxonomy Notes
The genus was described by Jacques Labillardière in Novae Hollandiae Plantarum Specimen vol. 1, p. 14 (1804), with the authorship cited as Labill. GBIF recognises approximately 112 descendants under its backbone entry (key 2731128) placed in family Cyperaceae, order Poales. PlantNET (citing K. L. Wilson, Flora of NSW vol. 4) places approximately 70 species worldwide.
