keys to the vascular plants of east texas - Botanical Research ...

630 CYPERACEAE/RHYNCHOSPORA
not officially designated as such (e.g., TOES 1993; Carr 2002d; Poole et al. 2002), given its limited
distribution in the state, we consider this variety to be of conservation concern in TX. �
Rhynchospora glomerata (L.) Vahl, (in compact clusters), CLUSTER BEAK-RUSH, CLUSTERED BEAK
SEDGE. Tufted perennial to 1.1(–1.5) m tall; inflorescences with clusters of spikelets (spikelets several–many
per cluster) usually borne in groups of more than 3; spikelets 4.5–6.5 mm long;
achenes 1.5–2 mm long, obovoid or orbicular lenticular; tubercle 1.3–1.8 mm long. Moist sandy
or peaty soils; widespread in e 1/3 of TX; e U.S from NJ s to FL w to IL and TX. Jun–Sep. [R.
cymosa Elliott, R. glomerata var. angusta Gale, R. glomerata var. paniculata Chapm.] According
to Kral (2002c), this species is often associated with R. capitellata and R. inexpansa.
Rhynchospora gracilenta A. Gray, (slender, gracefully slight in form), SLENDER BEAK SEDGE, SLEN-
DER BEAK-RUSH. Tufted perennial (10–)30–100 cm tall; inflorescences with spikelets in dense to
sparse, narrowly turbinate to hemispheric clusters; spikelets (3.5–)4–5(–6) mm long; achenes
1.3–1.8(–2.1) mm long, broadly ellipsoid to suborbicular, lenticular; tubercle nearly as long as
the achene or slightly longer, awl-shaped. Bogs, other moist areas, sandy or peaty soils; widespread
in East TX, apparently most abundant in the s Pineywoods; e U.S. from NY s to FL w to
OK and TX. Jun–Sep.
Rhynchospora grayi Kunth, (for Asa Gray, 1810–1888, botanist at Harvard and preeminent
American plant taxonomist), GRAY’S BEAK SEDGE, GRAY’S BEAK-RUSH. Coarse tufted perennial
usually 50–130 cm tall; leaf blades (1–)2.5–4 mm wide; inflorescences variable, loose to dense;
spikelets 4–6(–7.5) mm long; achenes 2–2.5 mm long, broadly obovoid, tumid, the summit often
abruptly narrowed, with a collar-like ring or ridge fitted against the tubercle (“apically buttressed
to tubercle”—Kral 2002d), dark brown, the surface with wavy horizontal lines of small
pit-like or raised structures (isodiametric cells); tubercle 0.4–0.6 mm long. Sandy pinelands,
“droughty sandhills, mostly in the longleaf pine-deciduous scrub oak systems” (Kral 1999);
Angelina, Hardin, Newton (BRIT), Liberty (Correll & Johnston 1970), Jasper, San Augustine,
and Tyler (Turner et al. 2003) cos.; se U.S. from VA s to FL w to TX. Jun–Sep. This species is similar
to R. harveyi but can be distinguished by its longer spikelets, longer achenes, and perianth
bristles usually reaching at least to the tubercle base (Kral 1999).
Rhynchospora harveyi W. Boott, (for its discoverer, Francis Leroy Harvey, 1850–1900, of NY),
HARVEY’S BEAK-RUSH, HARVEY’S BEAK SEDGE, PLANK BEAK-RUSH. Tufted perennial usually 50–110
cm tall; leaf blades 1.8–3 mm wide; inflorescences narrow, of 2–4 small clusters of spikelets;
spikelets 3–3.5(–4) mm long, mostly 1-fruited; bristles < 1/2 length of achene; achenes 1.5–1.7
mm long, obovoid to subglobose, the summit often abruptly narrowed, with a collar-like ring
or ridge fitted against the tubercle (apically “buttressed” to tubercle—Kral 2002d), tumid or lenticular,
the surface with wavy horizontal lines of small pit-like or raised structures (isodiametric
cells); tubercle conic, 0.3–0.5(–0.7) mm long. Areas that are at least seasonally moist in a variety
of habitats ranging from basic prairie soils to more acidic, upland, wooded, sandy soils;
widespread in e 1/3 of TX; mainly se U.S. from VA s to FL w to KS, OK, and TX. May–Jul(–Aug).
[R. earlei Britton, R. plankii Britton ex Small]
Rhynchospora indianolensis Small, (of Indianola, TX), INDIANOLA BEAK SEDGE, INDIANOLA BEAK-
RUSH. Tufted perennial to 1 m tall, without rhizomes; inflorescences terminal and axillary, the
clusters nearly in umbels, some clearly pedunculate, hemispheric to nearly capitate; spikelets
6–7 mm long; achenes 3–4 mm long, obovoid, the surfaces level or concave, the margins thick,
crimped; tubercle 3–4 mm long, conic, its base widened and capping the summit of the achene.
Ditches, prairie swales, other wet areas; Colorado and Harris (Carr 2001) cos.; mainly Gulf Prairies
and Marshes; endemic to TX (Kartesz 1999; Kral 2002c). May–Nov. This species has been
considered by some authorities (e.g., Thomas 1992) to be conspecific with R. scutellata Griseb. a
species ranging from the West Indies through Central America to Argentina; however, we are