Scleria microcarpa Nees ex Kunth

Global description

Scleria microcarpa is a large vivacious sedge in a loose clump. The culm is triangular in cross-section, smooth. The leaves have a three-winged sheath, a triangular ligule opposite the leaf blade and a smooth flexible linear leaf blade with a finely scabrous margin. The inflorescence consists of 3 to 8 stepped, very narrow, spiciform, erect panicles. The female spikelets are sessile with oval, keeled, distichous glumes terminating in a very short, unscurved point. The achene is oblong, smooth, shiny, green or white, with a point at the top and a cupped disc at the base that is much wider than the achene and has a ciliated margin.

General habit

Scleria microcarpa is a large vivacious sedge forming loose clumps of several single axes (1 to 20), 50 to 150 cm high.

Underground system

A rather large, scaly, fibrous, creeping, woody rhizome from which fibrous, fasciculated roots develop.

Culm

The culm is erect, distinctly triangular in cross-section, smooth and glabrous, and ridged. It is 50 to 150 cm high and 2 to 7 mm in diameter at the base. Within a clump the axes are more or less close to each other.

Leaf

The leaves are simple, alternate, widely spaced, and tristically arranged. They are green in colour. The sheath is triangular in cross-section with broad wings at each angle. At the top of the sheath and opposite the blade is a triangular ligule 4-8 mm high, more or less cartilaginous and finely scabrous at the margin. The leaf blade is linear and flexible, 20 to 45 cm long and 6 to 13 mm wide, abruptly narrowed in the distal half. Both sides are glabrous. The margin and midrib on the lower side are finely scabrous. The apex is acute wedge-shaped and the base is equally broad and continuous with the wings of the sheath. The section of the leaf blade forms an inverted W.

Inflorescence

The inflorescence consists of several (3-8) narrow, erect, spiciform panicles 6-12 cm long. Each panicle is very few and very short-branched. The branches are ascending, bearing spaced groups of spikelets.

Spikelet

The spikelets are unisexual, sessile, often in groups of 2 or 3, a female spikelet often being associated with 1 or 2 male spikelets. The female spikelet is globose, slightly compressed, 2 mm long and 1.7 mm in diameter, consisting of 3 pale green, broadly ovate distichous glumes, very short acuminate at the apex and with a green keel. They are 1.2 to 1.7 mm long, and do not extend beyond the edge of the disc. The tip of the apex is very short and not scurved. The male spikelet is fusiform with 3 distichous green glumes which are narrower than those of the female spikelet. It is 1.5 to 2 mm long and 1 mm in diameter.

Fruit

The fruit is an ovoid oblong achene, 1 to 1.7 mm long and 0.9 to 1.3 mm in diameter, green, white or cream in colour, smooth and shiny, topped by a cylindrical tip 0.3 mm long. The lower 1/3 or 1/2 of the achene is enclosed in a cup-shaped disc which is clearly wider than the achene and has a ciliated margin of white hairs.

Origin

Scleria microcarpa is native to and occurs only in Central America, the Caribbean and the tropical part of South America.

https://www.gbif.org/species/2712277