Sedum obtusatum

A. Gray

Proc. Amer. Acad. Arts 7: 342. 1868,.

Endemic
Synonyms: Gormania obtusata (A. Gray) Britton
Treatment appears in FNA Volume 8. Treatment on page 217. Mentioned on page 201, 202.
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Herbs, perennial, tufted, glabrous. Stems rootstocks, horizontal, branched, bearing terminal rosettes. Leaves alternate, ascending, sessile; blade green, blue-green, green suffused with red, or red, margins not white, not pruinose, not glaucous, obovate, spatulate, or oblanceolate, subterete to somewhat flattened, (4–) 12–22 (–33) × 4–10 mm, base not spurred, not scarious, apex rounded or truncate, obscurely mucronate, retuse, or emarginate. Flowering shoots (terminal or axillary), ascending, simple or branched, 2–10 (–12) cm; leaf-blades truncately obovate or spatulate, base not spurred; offsets not formed. Inflorescences paniculate cymes, 5–45-flowered, 4–15-branched; branches not recurved, simple or 1–2-forked; bracts spatulate to linear-oblong, 3–5 mm, base not spurred; offsets not formed. Pedicels 2–5 mm. Flowers ca. 5-merous; sepals erect, (loosely appressed to corolla), slightly connate basally, pale green or purplish, glaucous, ovate or lanceolate, (slightly subterete), equal, 1.8–5.3 (–6) × 2 mm, apex acute to obtuse; petals (convolute in bud), erect proximally, connate basally, spreading distally, greenish white or creamy white to yellow or pale orange, or pale orange suffused with pink, oblanceolate-oblong, spatulate or obovate, somewhat carinate, 4–10 mm, apex abruptly mucronate; filaments white or yellow; anthers yellow; nectar scales white, truncately reniform. Carpels erect in fruit, distinct, brown. 2n = 30, 60 (in var. retusum).

Discussion

Varieties 4 (4 in the flora).

R. T. Clausen (1975) noted that Sedum obtusatum, S. laxum, and S. oregonense are remarkably similar; S. obtusatum is distinct where it occurs with the other two but is difficult to distinguish by any single feature. Sedum obtusatum is unusual in having offsets produced in the axils of rosette leaves rather than on a rootstock or creeping stem.

Selected References

None.

Key

1 Petals yellow, sometimes with reddish veins; anthers 1.7-1.8 mm. Sedum obtusatum var. obtusatum
1 Petals white, greenish or creamy white, pale orange, or pale orange suffused with pink; anthers 0.8-1.5 mm > 2
2 Flowering shoots 9-12 cm. Sedum obtusatum var. boreale
2 Flowering shoots 2-9 cm > 3
3 Rosettes dense, internodes not visible. Sedum obtusatum var. paradisum
3 Rosettes loose, internodes visible. Sedum obtusatum var. retusum
... more about "Sedum obtusatum"
perigynous +  and hypogynous +
mucronate +, acute +  and obtuse +
Hideaki Ohba +
A. Gray +
not scarious +
red +, punct +, green suffused with red +, blue-green +  and green +
lobed +  and toothed +
linear +  and orbiculate or spatulate terete semiterete or subterete +
0.1 cm1 mm <br />0.001 m <br /> (8 cm80 mm <br />0.08 m <br />) +
succulent +
spatulate +  and linear-oblong +
0.3 cm3 mm <br />0.003 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
not recurved +
1-2-forked +
not circumscissile +
whorled +, opposite +  and alternate +
not circumscissile +
Calif. +, Nev. +  and Oreg. +
yellow +  and white +
connate +  and distinct +
spreading;erect +
4-15-branched +  and 5-45-flowered +
axillary +  and terminal +
spatulate;obovate +
persistent +  and deciduous +
connate +
2.2 cm22 mm <br />0.022 m <br /> (3.3 cm33 mm <br />0.033 m <br />) +
not pruinose +
1.2 cm12 mm <br />0.012 m <br /> (2.2 cm22 mm <br />0.022 m <br />) +
not glaucous +
flattened +, subterete to somewhat +, oblanceolate +, spatulate +  and obovate +
4mm;10mm +
spatulate;reniform;spatulate;reniform;oblong;square;oblong +
semi-inferior +  and superior +
tenuinucellate +, crassinucellate +  and bitegmic +
0.2 cm2 mm <br />0.002 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
perigynous +  and hypogynous +
suffused with pink +, creamy white +  and yellow or pale orange or pale orange +
spreading +  and erect +
carinate +, obovate +, spatulate +  and oblanceolate-oblong +
0.4 cm4 mm <br />0.004 m <br /> (1 cm10 mm <br />0.01 m <br />) +
(3-)4-5(-12)[-30+]-carpellate +
distinct +  and connate +
Proc. Amer. Acad. Arts +
reticulate-papillose +  and reticulate +
ovoid;ellipsoid +
0.53 cm5.3 mm <br />0.0053 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
purplish +  and pale green +
lanceolate +  and ovate +
unequal +
2 cm20 mm <br />0.02 m <br /> (?) +
1 +  and many +
branched +  and simple +
10 cm100 mm <br />0.1 m <br /> (12 cm120 mm <br />0.12 m <br />) +
adnate +  and free +
antipetalous +
2 times as many as sepals +
much-branched +
creeping +  and procumbent +
ascending +  and erect +
succulent +
distinct +
Gormania obtusata +
Sedum obtusatum +
species +
not conspicuous +
perennial +, biennial +  and annual +
3 +  and 5 +