Eleocharis geniculata

(Linnaeus) Roemer & Schultes in J. J. Roemer et al.

in J. J. Roemer et al., Syst. Veg. 2: 150. 1817.

Common names: Bent spikerush
Illustrated
Basionym: Scirpus geniculatus Linnaeus Sp. Pl. 1: 48. 1753
Synonyms: Eleocharis capitata R. Brown Eleocharis caribaea (Rottbøll) S. F. Blake Eleocharis dispar E. J. Hill
Treatment appears in FNA Volume 23. Treatment on page 101. Mentioned on page 63, 97, 102.

Plants tufted, without creeping rhizomes. Culms to 45 cm × 0.2–1 mm. Leaves: distal leaf-sheaths persistent, firm, distally tightly sheathing, apex acute. Spikelets orbicular to ovoid, 1–9 × 1–4 mm, apex rounded to acute; proximal scale without flower, not amplexicaulous; floral scales to 125, 11–14 per mm of rachilla, tightly appressed, dark redbrown to stramineous, ovate to elliptic, 0.8–3 × 0.6–2 (–2.3) mm, membranous to cartilaginous, apex rounded to acute. Flowers: perianth bristles (0–) 4–8, typically 7, redbrown, rarely whitish, vestigial to much exceeding tubercle, typically equaling achene, spinules few to dense; styles 2-fid. Achenes brown ripening to black, biconvex, orbicular to obpyriform, 0.5–1.1 × 0.3–0.7 mm, apex rarely constricted proximal to tubercle, very finely reticulate at 40X. Tubercles stramineous to whitish, umbonate to subconic, 0.2–0.4 × 0.2–0.5 mm, apex rounded to acute. 2n = 10.


Phenology: Fruiting spring–winter (Mar–Dec).
Habitat: Brackish creeks, canal banks, dune depressions, hammocks, irrigation ditches, lakeshores, lagoons, mangrove thickets, maritime mud flats, ditches, salt marshes
Elevation: 0–1500 m

Distribution

V23 151-distribution-map.jpg

Ont., Ala., Ariz., Calif., Fla., Ga., Ill., Ind., La., Mich., Miss., Nebr., Nev., N.Mex., Ohio, Okla., Pa., Tex., Mexico, West Indies, Bermuda, Central America, South America, Asia, Africa, Pacific Islands

Discussion

The name Eleocharis caribaea (Rottbøll) S. F. Blake is considered by most contemporary authorities to be misapplied (K. L. Wilson 1990). Eleocharis geniculata has been reported from South Carolina; I have not seen a voucher.

Selected References

None.

Lower Taxa

None.

"shortened" is not a number.

... more about "Eleocharis geniculata"
black +  and brown +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.11 cm1.1 mm <br />0.0011 m <br />) +
orbicular;obpyriform +
0.3mm;0.7mm +
rounded;acute +
constricted +
Francis J. Menapace +
(Linnaeus) Roemer & Schultes in J. J. Roemer et al. +
flattened +
0 cm0 mm <br />0 m <br /> (6 cm60 mm <br />0.06 m <br />) +
persistent +
enlarged +
Scirpus geniculatus +
glumaceous +  and foliaceous +
2-ranked +  and arranged +
ascending +  and appressed +
parallel +  and divergent +
terete +, rolled +  and plicate +
Bent spikerush +
0 cm0 mm <br />0 m <br /> (45 cm450 mm <br />0.45 m <br />) +
0.2mm;1mm +
Ont. +, Ala. +, Ariz. +, Calif. +, Fla. +, Ga. +, Ill. +, Ind. +, La. +, Mich. +, Miss. +, Nebr. +, Nev. +, N.Mex. +, Ohio +, Okla. +, Pa. +, Tex. +, Mexico +, West Indies +, Bermuda +, Central America +, South America +, Asia +, Africa +  and Pacific Islands +
0–1500 m +
0.2 cm2 mm <br />0.002 m <br /> (0.23 cm2.3 mm <br />0.0023 m <br />) +
dark redbrown +  and stramineous +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
ovate +  and elliptic +
membranous +  and cartilaginous +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
hypogynous +  and subtending +
biconvex +  and trigonous +
Brackish creeks, canal banks, dune depressions, hammocks, irrigation ditches, lakeshores, lagoons, mangrove thickets, maritime mud flats, ditches, salt marshes +
multi-ranked +, 2-ranked +, 3-ranked +  and alternate +
flattened +
0 cm0 mm <br />0 m <br /> (6 cm60 mm <br />0.06 m <br />) +
with (1-)3-6(-30) bristles and/or scales +
Fruiting spring–winter (Mar–Dec). +
2-3(-4)-carpellate +
3 (?) +  and 1 (?) +
not amplexicaulous +
stramineous;medium brown or red brown or blackish brown +
in J. J. Roemer et al., Syst. Veg. +
ascending +  and horizontal +
caudex-like +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
adventitious +
basal +  and proximal +
2-keeled +
cylindric +
Illustrated +
0.1 cm1 mm <br />0.001 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
orbicular;ovoid +
1 +  and 3 +
septate +, hollow +  and solid +
compressed +, terete +  and trigonous +
papillate +
Eleocharis capitata +, Eleocharis caribaea +  and Eleocharis dispar +
Eleocharis geniculata +
Eleocharis (sect. Eleogenus) ser. Maculosae +
species +
stramineous;whitish +
0.2mm;0.4mm +
umbonate +  and subconic +
0.2mm +  and 0.5mm +
not +  and rhizomatous +
perennial +  and annual +