Cyperus concinnus (common name - trim flat-sedge)[1] is a sedge of the family Cyperaceae that is native to Australia, and found in New South Wales, Queensland, the Northern Territory, South Australia, Victoria and Western Australia.[2]
The tufted perennial rhizomatous sedge typically grows to a height of 0.2to and produces brown flowers. It has culms with a triangular cross section. The culms are slightly swollen at the base and rough and scabrous above with a length of and a diameter of . The leaves have a prominent transverse septa and are about the same length of the culms and have a width of . The inflorescences have three to five primary branches with a length up to forming clusters that have a diameter of about . There are one to six flattened spikelets per cluster with a length of and a width of .[1]
It is found in all the mainland states and territories of Australia except for South Australia.[3] In Western Australia it is found in swamps and around creeks and pools the Mid West, Pilbara and Goldfields-Esperance regions where it grows in sandy-clay soils.
It was first described in 1810 by Robert Brown as a part of the work Prodromus Florae Novae Hollandiae et Insulae Van Diemen.[4]