Rhynchospora gracilenta

Illustrator:

Copyright:

Plants perennial, densely cespitose or solitary, 10–100 cm; rhizomes absent. Culms mostly lax, ascending to leaningexcurved, leafy, linear to filiform, terete. Leaves shorter than culm; blades ascending, filiform to narrowly linear, proximally flat, 0.5–1.5 (–2.5) mm wide, margins distally strongly involute, apex trigonous, tapering. Inflorescences: spikelet clusters 1–3 (–4), proximalmost distant, dense to sparse, narrowly turbinate to hemispheric; peduncles and branches ascending; leafy bracts linearsetaceous, mostly overtopping clusters. Spikelets redbrown, ovoid to lanceoloid, (3.5–) 4–5 mm, apex acute; fertile scales ovate, 3–4.5 mm, apex acute, mucronate to awnedcuspidate. Flowers: bristles 6, mostly reaching tip of tubercle or beyond, antrorsely barbellate. Fruits 1–3 per spikelet, (2.5–) 3–3.5 (–4.1) mm; body dark-brown with small pale center, lenticular, broadly ellipsoid to suborbicular, 1.3–2.1 × 1.3–1.5 mm, smooth, margins narrow, flowing into tubercle; tubercle triangularsubulate, compressed, mostly 1.5–2 mm.

Phenology: Fruiting late spring–fall.
Habitat: Moist to wet sandy peaty substrates in ditches, bogs, seeps, wet savannas, barrens, and flatwoods
Elevation: 0–400 m

Ala., Ark., Del., Fla., Ga., La., Md., Miss., N.J., N.C., Okla., Pa., S.C., Tenn., Tex., Va., West Indies (Cuba), Central America

Discussion

Through the southern coastal plain are widerleaved examples of Rhynchospora gracilenta that are sparingly cespitose to solitary-stemmed, often with but a single terminal inflorescence with dense clusters of spikelets (var. diversifolia). That would be a tenable designation were it not for the large numbers of populations with intermediate habit.

Selected References

None.

Lower Taxa