Cyperus dentoniae

G. C. Tucker

Syst. Bot. Monogr. 2: 56. 1983.

Common names: Denton’s flatsedge
Illustrated
Basionym: Mariscus pubescens J. Presl & C. Presl 1828
Synonyms: Cyperus flavomariscus var. peduncularis Britton Cyperus flavus var. peduncularis (Britton) Kükenthal
Treatment appears in FNA Volume 23. Treatment on page 187. Mentioned on page 148, 185, 188.

Herbs, perennial, cespitose, shortly rhizomatous. Culms 1–4, trigonous, (2–) 20–50 (–80) cm × (0.8–) 1.5–2 (–2.8) mm, basally glabrous or nearly so, apically hispidulous, on faces and angles distally, especially so immediately proximal to bracts. Leaves 2–5 (–7), V-shaped, (5–) 15–30 (–45) cm × (1.5–) 2.5–5 (–8) mm. Inflorescences: spike 1 (occasionally 1–2 smaller sessile spikes at base), densely cylindric, (7–) 11–20 (–25) × (5–) 7–10 (–12) mm; rays 3–6 (–10), (1–) 3–6 (–18) cm, rays and rachis hispidulous; bracts 4–8 (–10), ascending at 30–60°, V-shaped, (2–) 10–25 (–45) cm × (1–) 3–6 (–8) mm; rachilla deciduous, wings persistent, 0.3–0.4 mm wide. Spikelets (20–) 70–120 (–140), oblongellipsoid to oblong-lanceoloid, ± terete to quadrangular, (2.2–) 3.4–4.5 (–5.6) × (0.8–) 0.9–1.2 (–1.3) mm; distal spikelet spreading or ascending; floral scales 1 (–3), appressed, stramineous, red-spotted, strongly 3 (–4) -ribbed on either side of green part, medially weakly 3-ribbed, ovate to elliptic ovate, (2.4–) 2.8–3.3 (–3.6) × 1.6–2 mm, apex acute, mucronulate from excurrent midrib. Flowers: anthers (0.3–) 0.4–0.6 mm; styles 0.4–0.6 (–0.8) mm; stigmas 1–1.4 mm. Achenes brown, stipitate, ellipsoid, (1.6–) 1.8–2 × (0.7–) 0.8–0.9 mm, stipe 0.1–0.2 × 0.2 mm, apex ± truncate, apiculate, surfaces puncticulate to glabrous.


Phenology: Fruiting mid summer–fall (Jul–Sep).
Habitat: Various dry, open environments
Elevation: 500–1000 m

Distribution

V23 324-distribution-map.jpg

Ariz., Mexico, Central America, South America

Discussion

Cyperus dentoniae was not treated in G. Kükenthal’s monograph (1935–1936), apparently because he did not see any materials of the species. The plant has been treated as “C. asper (Liebmann) O’Neill,” a name based on Mariscus asper Liebmann and a synonym of C. mutisii (A. B. Ayers 1946).

Selected References

None.

Lower Taxa

None.

"shortened" is not a number.

... more about "Cyperus dentoniae"
0.16 cm1.6 mm <br />0.0016 m <br /> (0.18 cm1.8 mm <br />0.0018 m <br />) +
0.07 cm0.7 mm <br />7.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
0.18 cm1.8 mm <br />0.0018 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
ellipsoid +
0.8mm;0.9mm +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.04 cm0.4 mm <br />4.0e-4 m <br />) +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (0.06 cm0.6 mm <br />6.0e-4 m <br />) +
apiculate +  and truncate +
mucronulate;acute +
Gordon C. Tucker* +, Brian G. Marcks* +  and J. Richard Carter * +
G. C. Tucker +
persistent +  and deciduous +
decurrent +
Mariscus pubescens +
w--shaped +  and keeled +
glumaceous +  and foliaceous +
2-ranked +  and arranged +
25 cm250 mm <br />0.25 m <br /> (45 cm450 mm <br />0.45 m <br />) +
0.6 cm6 mm <br />0.006 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
10 cm100 mm <br />0.1 m <br /> (25 cm250 mm <br />0.25 m <br />) +
v--shaped +
0.3 cm3 mm <br />0.003 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
parallel +  and divergent +
terete +, rolled +  and plicate +
Denton’s flatsedge +
50 cm500 mm <br />0.5 m <br /> (80 cm800 mm <br />0.8 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.28 cm2.8 mm <br />0.0028 m <br />) +
20 cm200 mm <br />0.2 m <br /> (50 cm500 mm <br />0.5 m <br />) +
hispidulous +, nearly +  and glabrous +
scabridulous +
trigonous +
1.5mm;2mm +
ascending +  and spreading +
Ariz. +, Mexico +, Central America +  and South America +
500–1000 m +
3-ribbed +  and 3(-4)-ribbed +
0.33 cm3.3 mm <br />0.0033 m <br /> (0.36 cm3.6 mm <br />0.0036 m <br />) +
red-spotted +  and stramineous +
deciduous +  and persistent +
0.28 cm2.8 mm <br />0.0028 m <br /> (0.33 cm3.3 mm <br />0.0033 m <br />) +
ovate +  and ovate to elliptic +
0.16 cm1.6 mm <br />0.0016 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
hypogynous +  and subtending +
biconvex +  and trigonous +
Various dry, open environments +
subumbellate +  and capitate +
spreading +  and erect +
multi-ranked +, 2-ranked +, 3-ranked +  and alternate +
30 cm300 mm <br />0.3 m <br /> (45 cm450 mm <br />0.45 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
15 cm150 mm <br />0.15 m <br /> (?) +  and 30 cm300 mm <br />0.3 m <br /> (?) +
v--shaped +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
with (1-)3-6(-30) bristles and/or scales +
Fruiting mid summer–fall (Jul–Sep). +
2-3(-4)-carpellate +
antrorse +  and extrorse +
3 (?) +  and 1 (?) +
Syst. Bot. Monogr. +
continuous +, articulate +, winged +  and wingless +
conspicuous +
hispidulous +
6 cm60 mm <br />0.06 m <br /> (18 cm180 mm <br />0.18 m <br />) +
unequal +
hispidulous +
3 +  and 6 +
3 cm30 mm <br />0.03 m <br /> (6 cm60 mm <br />0.06 m <br />) +
adventitious +
basal +  and proximal +
cylindric;compressed +
cylindric +
Illustrated +
2 cm20 mm <br />0.02 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
1 cm10 mm <br />0.01 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
1.1 cm11 mm <br />0.011 m <br /> (2 cm20 mm <br />0.02 m <br />) +
cylindric +
0.7 cm7 mm <br />0.007 m <br /> (1 cm10 mm <br />0.01 m <br />) +
0.45 cm4.5 mm <br />0.0045 m <br /> (0.56 cm5.6 mm <br />0.0056 m <br />) +
0.12 cm1.2 mm <br />0.0012 m <br /> (0.13 cm1.3 mm <br />0.0013 m <br />) +
0.34 cm3.4 mm <br />0.0034 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
70 +  and 120 +
less terete;quadrangular +
0.9mm;1.2mm +
septate +, hollow +  and solid +
compressed +, terete +  and trigonous +
papillate +
0.1 cm1 mm <br />0.001 m <br /> (0.14 cm1.4 mm <br />0.0014 m <br />) +
0.01 cm0.1 mm <br />1.0e-4 m <br /> (?) +  and 0.02 cm0.2 mm <br />2.0e-4 m <br /> (?) +
0.2 cm2 mm <br />0.002 m <br /> (?) +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
2-3-fid +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (0.06 cm0.6 mm <br />6.0e-4 m <br />) +
Cyperus flavomariscus var. peduncularis +  and Cyperus flavus var. peduncularis +
Cyperus dentoniae +
Cyperus subg. Cyperus +
species +
herb +  and cespitose +
persistent +
0.3mm +  and 0.4mm +