Eleocharis brachycarpa

Svenson

Rhodora 31: 200, plate 190, fig. 34. 1929.

IllustratedConservation concern
Treatment appears in FNA Volume 23. Treatment on page 111. Mentioned on page 108, 109.

Plants annual, densely cespitose; rhizomes obscured among culm bases, 0.2 mm thick, internodes to 4 mm, scales not evident. Culms mostly ascending, 4-angled, sulcate, 5 cm × 0.1–0.2 mm, soft. Leaves: distal leaf-sheaths persistent, colorless, translucent, apex narrowly acute. Spikelets ovoid, 2–3 × 1–2 mm, apex blunt; floral scales 10–30, ca. 10 per mm of rachilla, orangebrown to stramineous with broad colorless margin, midrib region stramineous, lanceolate, folded lengthwise, 1.5–2 × 0.8–1 mm, midrib prominent, apex acuminate. Flowers: perianth bristles absent; anthers 0.7–1.2 mm. Achenes whitish, broadly obpyriform, much less than 2 times longer than wide, angles and longitudinal ridges ca. 6, obscure, 0.4 × 0.3 mm, apex blunt, trabeculae 20, indistinct, crowded. Tubercles brownish, not appressed, mostly pyramidal, 0.1 × 0.1 mm.


Phenology: Fruiting winter–spring.
Habitat: Wet soils
Elevation: 0–20 m

Discussion

Of conservation concern.

Eleocharis brachycarpa is unique among the North American members of subg. Scirpidium in its floral scales, which are markedly spreading in fruit, often apparently decussate when pressed, narrowly lanceolate, and folded lengthwise so that they do not press open and flat. It is apparently very rare and local. It is admitted to the flora only on the basis of labels on a paratype (Berlandier 996) and on Berlandier 2426, both of which read “In locis paludosis – De Matamoros a las Nueces [River, Texas], Ap. 1834.” H. K. Svenson (1929) mistranscribed the locality “Nueces,” publishing it as “Mueres.” We have also seen a specimen from Mexico, Tamaulipas, 24 mi. N of San Fernando, edges of resacas, elev. 15 m, 1959, M.C. Johnston 4882C (TEX).

Selected References

None.

Lower Taxa

None.
... more about "Eleocharis brachycarpa"
obpyriform +
0.4 cm4 mm <br />0.004 m <br /> (?) +
0.07 cm0.7 mm <br />7.0e-4 m <br /> (0.12 cm1.2 mm <br />0.0012 m <br />) +
S. Galen Smith* +, Jeremy J. Bruhl* +, M. Socorro González-Elizondo* +  and Francis J. Menapace* +
Svenson +
flattened +
0 cm0 mm <br />0 m <br /> (6 cm60 mm <br />0.06 m <br />) +
shortened +
persistent +
enlarged +
Undefined subg. Scirpidium +
glumaceous +  and foliaceous +
2-ranked +  and arranged +
ascending +  and appressed +
parallel +  and divergent +
terete +, rolled +  and plicate +
5 cm50 mm <br />0.05 m <br /> (?) +
4-angled +
0.1mm;0.2mm +
Tex. +  and Mexico (Tamaulipas) +
0–20 m +
orangebrown +  and stramineous +
0.1 cm1 mm <br />0.001 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
subtending +
biconvex +  and trigonous +
Wet soils +
0 cm0 mm <br />0 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
multi-ranked +, 2-ranked +, 3-ranked +  and alternate +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
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 winter–spring. +
2-3(-4)-carpellate +
3 (?) +  and 1 (?) +
stramineous;medium brown or red brown or blackish brown +
ascending +  and horizontal +
caudex-like +
0.2 cm2 mm <br />0.002 m <br /> (?) +
adventitious +
basal +  and proximal +
not evident +
2-keeled +
cylindric +
Illustrated +  and Conservation concern +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
proliferating +
0.2 cm2 mm <br />0.002 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
1 (?) +  and 3 (?) +
septate +, hollow +  and solid +
compressed +, terete +  and trigonous +
papillate +
Eleocharis (sect. Undefined) ser. Aciculares +
Eleocharis brachycarpa +
Eleocharis subg. Scirpidium +
species +
pyramidal +
0 +  and 10 +
stoloniferous +  and rhizomatous +
plant +  and cespitose +