Species

Isolepis levynsiana

Etymology

Isolepis: From the Greek isos (equal) and lepis (scale)

Common Name(s)

tiny flatsedge

Authority

Isolepis levynsiana Muasya et D.A.Simpson

Family

Cyperaceae

Brief Description

Tiny fine-leaved grass- or rush-like clump or mat forming plant, up to 10 cm tall, with flattened head heads, usually 2 per stem.

Flora Category

Vascular - Exotic

NVS Species Code

ISOLEV

The National Vegetation Survey (NVS) Databank is a physical archive and electronic databank containing records of over 94,000 vegetation survey plots - including data from over 19,000 permanent plots. NVS maintains a standard set of species code abbreviations that correspond to standard scientific plant names from the Ngä Tipu o Aotearoa - New Zealand Plants database.

Structural Class

Sedges

Synonyms

Cyperus tenellus L.f. Until recently known as Cyperus tenellus L.f. Isolepis tenellus (L.f.) Muasya et D.A.Simpson is illegitimate

Distribution

Scattered through the North Island and Nelson in the South Island, usually lowland.

Habitat

Margins of water bodies, wet roadsides.

Features

Small tufted annual, 2-10 cm high. Stems numerous, filiform. Leaves 1-2 basal, much > stems, setaceous; sheaths hyaline, mostly colourless but occasionally red-tinged at base. Inflorescence a solitary cluster of (1)-2-(5) comparatively large, digitate, very compressed spikelets varying from whitish-green to greenish-brown; lower subtending bract setaceous, < or > inflorescence, appearing as a continuation of the stem, occasionally a second setaceous bract or an upper spikelet with a short glume-like bract. Spikelets ± 3-8 × 2-3 mm, oblong to ovate-lanceolate. Glumes many, densely imbricate, ± 2 mm long, obtuse, distinctly nerved, margins occasionally brown-splotched, keel green, later brown, tip slightly spreading. Stamens 1 or 2. Style-branches 3. Nut slightly > ½ length of glume, ellipsoid, acutely triquetrous.

Similar Taxa

Similar to many other Isolepis species and also young toad rush (Juncus bufonius), but none of these plants produce flattened spikelets.

Flowering

Throughout most of the year

Flower Colours

Green

Fruiting

Throughout most of the year

Year Naturalised

1863

Origin

South Africa and Australia

Reason for Introduction

Unknown, seed or soil contaminant.

Control Techniques

Rarely controlled, but can be controlled manually, mechanically or herbicidally depending on situation.

Life Cycle and Dispersal

Seed dispersed by water or contaminated machinery.

Notes on taxonomy

Muasya, A.M; Simpson, D.A.; Smets, E. 2007: Isolepis levynsiana, a new name for Cyperus tenellus (Cyperaceae). Novon 17: 59

Attribution

Factsheet prepared by Paul Champion and Deborah Hofstra (NIWA). Factsheet descriptions from Croasdale et al., (1994).

References and further reading

Healy, A.J.; Edgar, E.  (1980). Flora of New Zealand, Volume III.  Adventive Cyperaceous, Petalous and Spathaceous Monocotyledons.  Government Printer, Wellington.  220pp.

Johnson, A. T. and Smith, H. A (1986). Plant Names Simplified: Their pronunciation, derivation and meaning. Landsman Bookshop Ltd: Buckenhill, UK.

Popay et al (2010).  An illustrated guide to common weeds of New Zealand, third edition.  NZ Plant Protection Society Inc, 416pp.

This page last updated on 5 Jun 2014