Isolepis setacea

(Linnaeus) R. Brown

Prodr., 222. 1810.

IntroducedIllustrated
Basionym: Scirpus setaceus Linnaeus Sp. Pl. 1: 49. 1753
Treatment appears in FNA Volume 23. Treatment on page 140. Mentioned on page 138, 139.

Plants perennial (annual?), forming dense mats; rhizomes creeping; culms, leaves, and bracts orange-punctate at 10–15X. Culms 3–25 cm × 0.2–0.3 mm. Leaves: sheaths usually reddish proximally; distal blade rudimentary to 6 cm × 0.2–0.5 mm. Inflorescences: involucral-bracts 1 or 2; proximal bract erect to spreading, 3–10 (–20) mm; distal bract reflexed, to 5 mm. Spikelets 3–6 × 2 mm; scales partly orange to red or blackish brown, midrib greenish to stramineous, not gibbous, prominently ribbed near midrib, often with 1+ pale veins on dark sides, 1.2–1.6 × 0.6–1 mm, membranous, hyaline, apex rounded to obtuse, mucro to 0.1 mm; proximal scale-like others. Flowers: anthers 0.3–0.5 mm; styles 3-fid or 3-fid and 2-fid. Achenes falling separately from floral scales, orangebrown, each face prominently longitudinally 5–8-ribbed, many fine transverse ridges evident at 20–30X, broadly obovoid to oblong, thickly biconvex to compressedtrigonous, abaxial angle obscure, lateral angles prominent, faces convex, 0.8–1 × 0.5 mm. 2n = 28.


Phenology: Fruiting late spring–fall.
Habitat: Stream banks, pond margins, ditches, coastal, rarely inland
Elevation: 0–1500 m

Distribution

V23 222-distribution-map.jpg

Introduced; B.C., Calif., Oreg., Wash., Eurasia, Africa, Australia (including Tasmania), New Zealand

Discussion

Isolepis setacea belongs to a distinct group of species characterized by ridged achenes (A. M. Muasya et al. 2001). Isolepis setacea was collected in 1874 on waste at Camden, New Jersey, and in the 1880s at Philadelphia, Pennsylvania; it has not persisted in the East. It has been known from the Pacific Coast since at least 1921. It is reported as native to Eurasia and Africa. It is cultivated as an ornamental.

Selected References

None.

Lower Taxa

None.
... more about "Isolepis setacea"
orangebrown +
papillose +
trigonous;biconvex +
prominent +  and obscure +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
S. Galen Smith +
(Linnaeus) R. Brown +
shortened +
persistent +
enlarged +
Scirpus setaceus +
rudimentary +
glumaceous +  and foliaceous +
2-ranked +  and arranged +
ascending +  and appressed +
parallel +  and divergent +
terete +, rolled +  and plicate +
prominent +  and obscure +
3 cm30 mm <br />0.03 m <br /> (25 cm250 mm <br />0.25 m <br />) +
0.2mm;0.3mm +
0 cm0 mm <br />0 m <br /> (6 cm60 mm <br />0.06 m <br />) +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
B.C. +, Calif. +, Oreg. +, Wash. +, Eurasia +, Africa +, Australia (including Tasmania) +  and New Zealand +
0–1500 m +
prominent +  and obscure +
convex;biconvex;broadly obovoid;oblong +
hypogynous +  and subtending +
biconvex +  and trigonous +
Stream banks, pond margins, ditches, coastal, rarely inland +
solitary +  and capitate +
spreading +  and erect +
multi-ranked +, 2-ranked +, 3-ranked +  and alternate +
cauline +  and basal +
hyaline +, greenish +  and stramineous +
0.12 cm1.2 mm <br />0.0012 m <br /> (0.16 cm1.6 mm <br />0.0016 m <br />) +
not gibbous +
membranous +
0.6mm;1mm +
0 cm0 mm <br />0 m <br /> (0.01 cm0.1 mm <br />1.0e-4 m <br />) +
with (1-)3-6(-30) bristles and/or scales +
Fruiting late spring–fall. +
2-3(-4)-carpellate +
3 (?) +  and 1 (?) +
1 cm10 mm <br />0.01 m <br /> (2 cm20 mm <br />0.02 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (1 cm10 mm <br />0.01 m <br />) +
0.8mm;1mm +
adventitious +
partly orange +  and red or blackish brown +
basal +  and proximal +
2-keeled +
cylindric +
Introduced +  and Illustrated +
0.3 cm3 mm <br />0.003 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
1 (?) +  and 3 (?) +
septate +, hollow +  and solid +
compressed +, terete +  and trigonous +
papillate +
2-fid +  and 3-fid +
Scirpus sect. Isolepis +
Isolepis setacea +
Isolepis +
species +
not +  and rhizomatous +