Pharus glaber |
Pharus |
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upsidedown grass |
stalkgrass |
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Habit | Plants cespitose. | Plants perennial, some apparently monocarpic; rhizomatous, sometimes cespitose or stoloniferous; monoecious. |
Culms | 25-95 cm, generally decumbent and rooting at the nodes. |
10-130 cm, erect to decumbent; internodes solid, frequently with prominent prop roots at the lower nodes. |
Sheaths | glabrous, extensively overlapping; ligules 1-2 mm; pseudopetioles 8-60 mm; blades 7-30 cm long, 2-6.5 cm wide, narrowly elliptic to obovate, often acuminate, lacking intercostal fibrous bands, sometimes whitened beneath, lateral veins diverging from the midvein at a 4-8° angle. |
open, glabrous; ligules usually scarious, sometimes membranous and ciliate; pseudopetioles conspicuous, twisted 180° distally, inverting the blades; blades linear to ovate, usually broad, usually tessellate, lateral veins diverging obliquely from the midvein. |
Panicles | 10-40 cm, sparsely flowered; branches solitary, with uncinate hairs, usually tipped with a staminate spikelet. |
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Inflorescences | terminal panicles, ovate, open; rachises terminating in a staminate spikelet or naked; branches with uncinate hairs, spikelets appressed. |
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Spikelets | unisexual, dimorphic, sexes paired or pistillate spikelets solitary, with 1 floret; rachillas not prolonged beyond the florets; disarticulation above the glumes and in the panicle branches. |
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Staminate | spikelets 2.5-3.5 mm, on 4-11 mm pedicels, subtending the pistillate spikelets, purple; lower glumes 1-2 mm; upper glumes 1.5-3.2 mm, 1- or 3-veined; lemmas 2.5-3.5 mm; paleas about 3/4 the length of the lemmas; anthers 0.9-1.1 mm. |
spikelets smaller than the pistillate spikelets, attached below the pistillate spikelets on appressed pedicels; lower glumes shorter than the upper glumes or absent; lemmas longer than the glumes, ovate, 3-veined; lodicules 3, minute; anthers 6. |
Pistillate | spikelets 7.5-12 mm, diverging slightly from the branches; glumes brown; lower glumes 5-7 mm, 5-7-veined; upper glumes 6-8 mm, 3-5-veined; lemmas 7.5-12 mm, linear-oblong, abruptly short-beaked, with uncinate hairs nearly to the base; paleas equaling the lemmas. |
spikelets larger than the staminate spikelets, subsessile, elongate; glumes subequal, lanceolate, (3)5-9(11)-veined, purple or green; lemmas cylindrical, longer than the glumes, indurate, involute, with uncinate hairs over at least a portion of the surface, 7-veined, margins inrolled, concealing the palea; lodicules absent; staminodes 6, minute; styles 1, 3-branched, stigmas hispid, x = 12. |
2n | = 24. |
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Pharus glaber |
Pharus |
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Distribution |
FL; PR; Virgin Islands |
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Discussion | Pharus glaber grows on limestone-influenced sand in the hammocks of central Florida. Only two remaining populations are known in the United States, but the species is still widely present elsewhere in the Neotropics. Hitchcock (1951) erroneously referred this species to Pharus parvifolius Nash, which differs primarily in the presence of intercostal fibrous bands on the adaxial surfaces of the leaf blades. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Pharus includes eight species. It extends from central Florida through Mexico to Argentina and Uruguay, and grows in moist to wet lowland forests. One species, Pharus glaber, is native to the Flora region. The uncinate hairs and disarticulating panicle branches of Pharus promote dispersion by attaching to the coats of passing animals. The inverted, pseudopetiolate leaf blades and oblique venation make the genus easily distinguished, even in its vegetative state. Well-preserved female spikelets resembling those of Pharus mezii Prod, have been found in 30-45 million-year-old amber. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 24, p. 13. | FNA vol. 24, p. 12. |
Parent taxa | Poaceae > subfam. Pharoideae > tribe Phareae > Pharus | Poaceae > subfam. Pharoideae > tribe Phareae |
Subordinate taxa | ||
Name authority | Kunth | P. Browne |
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