Scleria

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Scleria

Description

Monoecious (only the Australian S. sphacelata F.v.M. dioecious). Perennial. often stout herbs with short or creeping, often nodose rhizome, or annuals with fibrous, reddish roots. Leaves 3-ranked, linear, sheathing the stem, smooth to very scabrous on the margins and the main nerves, the lower ones reduced to bladeless or almost bladeless sheaths; Inflorescence paniculate, consisting of a terminal partial panicle and usually some lateral ones, sometimes reduced to dense clusters, or glomerate-spiciform with glume-like bracts. Flowers unisexual, achlamydeous, the ♂ ones consisting of 1-3 stamens;

Distribution

Africa: present Asia-Tropical: Japan extending beyond the 40th N. parallel: present N. America extending beyond the 40th N. parallel: present Pantropical: present S. Africa reaching the 35th S. parallel: present S. America reaching the 35th S. parallel: present wide Asian or Australasian distribution: present
Large genus of about 200 spp., mainly pantropical, but in N. America extending beyond the 40th N. parallel and Japan extending beyond the 40th N. parallel, and in S. America reaching the 35th S. parallel and S. Africa reaching the 35th S. parallel; see map in . In Malesia 34 spp. occur, of which only 5 are endemic (no 1, 2, 3, 5, and 32). Almost all others have a wide Asian or Australasian distribution, a few occur even also in Africa, and a single one, S. lithosperma, is pantropic in distribution. It is remarkable that of these some have only a very few stations in Malesia.

Taxonomy

In nearly all Scleria spp. the glumes of the ♀ (or bisexual) spikelets are persistent on the peduncle after the falling out of the nut. In S. caricina (and in the closely related S. reticulata) they fall off with the ripe nut which they enclose like a sort of perigynium not unlike the utricle in Carex. On this character R. BROWN based his genus Diplacrum. After KUNTH had shown that the glumes in Diplacrum and the utricle in Carex are not homologous, BENTHAM merged Diplacrum with Scleria. Serious objections against their congenerity were again raised by GOEBEL, who was of the opinion that the distribution of the sexes in the inflorescence and the structure of the nut-bearing spikelets in Diplacrum are essentially different from those in Sc/eria. According to me the inflorescence in Diplacrum represents but one of the numerous variations in type occurring in Scleria, and both in Scleria and Diplacrum the ♀ flower is terminal, so that there is no valid point of generic discrimination.
The Asiatic Scleriae (with the exception of Diplacrum) are generally subdivided into two subgenera, Scleria proper and Hypoporum, the former with none or few bisexual spikelets and usually a well-developed hypogynous disk, the latter with many bisexual spikelets and a much reduced disk. As this subdivision is far from being natural, it has not been accepted here. See .

Uses

The genus has hardly any economic value. The leaves of S. poaeformis are sometimes used for matting purposes, those of S. pergracilis as a medicine, and young plants of S. biflora are eaten with the rice as 'lalab'.

Notes

A few species are aromatic, S. pergracilis is strongly lemon-scented; of S. biflora young plants are fragrant, its roots smelling of camphor or cajaput.

Citation

BOECK. - in Linnaea. 1874
KERN - in Blumea. 1961: 140