Fimbristylis cymosa R.Br.

Authority

Acevedo-Rodríguez, Pedro & collaborators. 1996. Flora of St. John, U.S. Virgin Islands. Mem. New York Bot. Gard. 78: 1-581.

Family

Cyperaceae

Scientific Name

Fimbristylis cymosa R.Br.

Description

Species Description - Perennial, 5-60 cm tall; rhizome short, thick; culms erect, rigid, obscurely 3-angled or cylindrical, 0.5-2 mm wide at base, coarsely ribbed, green to straw-colored, the stout, sheathing bases hard and stiff, with remnants of old leaf bases. Leaves many; blades stiff, flat to somewhat inrolled, spreading, frequently falcate, 3-25 cm long, 0.8-4 mm wide, obscurely veined, green to straw-colored, glabrous, scabrous on margins, the apex with a curved tip; sheaths short, rigid, prominently veined, glabrous, pale green to dark brown, eligulate, the membranous inner band abruptly narrowing into the blade, with a concave orifice at summit. Inflorescence an open to congested, simple or compound cyme, 4-8 cm diam.; involucral bracts 1-3, leaflike, linear to subulate, shorter than the inflorescence or the lowest one sometimes exceeding the inflorescence; rays compressed, to 3 cm long, or wanting; spikelets ovate, 3-4 x 1.8-2.5 mm; scales ovate, slightly keeled, 1.2-1.6 X 0.8-1.2 mm , 3-nerved on keel, green to brown, with broad, scarious margins, the narrow, light green midrib extending as a short mucro below the obtuse to emarginate apex. Stamens 2, the anthers linear to narrowly elliptic, 0.5-0.7 mm long, apiculate at apex; styles 2-branched to below the middle, the unbranched portion glabrous, entire, 3-angled at expanded base. Achene unequally 2-sided, turgid on both faces, obovoid, 0.8-0.9 x 0.5-0.7 mm , broadly rounded to truncate at apex, narrowed to base, verrucose-reticulate, light brown, becoming dark brown to essentially black at maturity.

Discussion

Fimbristylis spathacea Roth, Nov. PL Sp. 24. 1821. Fimbristylis cymosa ssp. spathacea (Roth) T. Koyama, Micronesica 1: 83. 1964.

Scirpus obtusifolius sensu Griseb., Fl. Brit. W . I. 571. 1864, non Lam., 1791.

Distribution

A common herb of coastal areas, along beaches, roadsides, and disturbed habitats. Coral Bay (A2660), Great Cmz Bay (A796), Center Line Road (A3783). Also on St. Croix; a pantropical weed.

Saint Croix Virgin Islands of the United States South America|