Ivesia paniculata

T. W. Nelson & J. P. Nelson

Brittonia 33: 165, fig. 1. 1981.

Common names: Ash Creek ivesia
Conservation concernEndemic
Treatment appears in FNA Volume 9. Treatment on page 229. Mentioned on page 220, 221, 223.

Plants grayish, ± matted. Stems ± prostrate, 0.4–1.5 (–2) dm. Basal leaves tightly cylindric, (1.5–) 2–5 (–7) cm; sheathing base densely hairy abaxially; petiole 0.5–4 cm; lateral leaflets (5–) 8–15 per side, overlapping at least distally, ± flabellate, 0.5–2 mm, incised to base or nearly so into (0–) 3–8 (–15) elliptic to narrowly obovate lobes, apex not or obscurely setose, surfaces densely hirsute, cryptically glandular; terminal leaflets indistinct. Cauline leaves (0–) 1; blade reduced. Inflorescences 20–200-flowered, congested, (1–) 1.5–6 (–10) cm diam. Pedicels 1.5–6 mm. Flowers 4–6 mm diam.; epicalyx bractlets 5, lanceolate to elliptic, 0.6–1.5 (–2) mm; hypanthium shallowly cupulate, 1 × 2–3 mm; sepals (1–) 1.5–2.5 (–3) mm, acute; petals white to pale yellowish, linear, 1 mm; stamens 5, filaments 0.3–1 mm, anthers yellow with maroon margins, ovate, 0.3–0.5 mm; carpels 1–2 (–3), styles 0.7–1.8 mm. Achenes brown, 0.8–1.5 mm, smooth, prominently carunculate.


Phenology: Flowering summer.
Habitat: Dry shallow volcanic ash and cinders atop volcanic bedrock, open sagebrush communities, adjacent conifer woodlands
Elevation: 1500–1800 m

Discussion

Of conservation concern.

Ivesia paniculata is known only from the Ash Valley area of Lassen County. The distinctions between I. paniculata and I. rhypara are perhaps on the same scale as variation among disjunct population clusters of I. rhypara, but no taxonomic adjustments are proposed at this time.

Selected References

None.

Lower Taxa

None.

"thin" is not a number."dm" is not declared as a valid unit of measurement for this property."dm" is not declared as a valid unit of measurement for this property."dm" is not declared as a valid unit of measurement for this property.

... more about "Ivesia paniculata"
0.8mm +  and 1.5mm +
shorter than wide +  and longer +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
obtuse;rounded +
Barbara Ertter +  and James L. Reveal +
T. W. Nelson & J. P. Nelson +
compound +  and simple +
opposite +  and alternate +
5 cm50 mm <br />0.05 m <br /> (7 cm70 mm <br />0.07 m <br />) +
2 cm20 mm <br />0.02 m <br /> (5 cm50 mm <br />0.05 m <br />) +
Setosae +
20 cm200 mm <br />0.2 m <br /> (25 cm250 mm <br />0.25 m <br />) +
narrowly oblong +  and filiform planar +
reduced +
0.5 cm5 mm <br />0.005 m <br /> (20 cm200 mm <br />0.2 m <br />) +
coriaceous +
reduced +
elongate +
free +  and distinct +
branched +  and simple +
Ash Creek ivesia +
not +  and aggregated +
1500–1800 m +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
lanceolate +  and elliptic +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
0.4 cm4 mm <br />0.004 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
unisexual +  and bisexual +
not +  and aggregated +
deciduous +
obliquely ovoid +  and reniform +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
loose +  and capitate +
Dry shallow volcanic ash and cinders atop volcanic bedrock, open sagebrush communities, adjacent conifer woodlands +
0.3 cm3 mm <br />0.003 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
1.5 cm15 mm <br />0.015 m <br /> (6 cm60 mm <br />0.06 m <br />) +
crassinucellate +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
opposite +  and alternate +
winter-marcescent +
deciduous +  and persistent +
separate +  and overlapping +
, +  and distinct +
distinguishable +
lobed +  and toothed +
obovate +  and elliptic +
verticillate +
toothed +, unlobed +  and lobed +
inferior +  and superior +
clustered +, biseriate +  and superposed +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
0 (?) +  and 4 (?) +
white +  and pale yellowish +
free +  and distinct +
not clawed +
1 cm10 mm <br />0.01 m <br /> (?) +
0.5 cm5 mm <br />0.005 m <br /> (4 cm40 mm <br />0.04 m <br />) +
Flowering summer. +
adnate +, free +, connate +  and distinct +
not arillate +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
persistent +
free +  and distinct +
erect +  and spreading +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
Conservation concern +  and Endemic +
free +  and distinct +
branched +  and simple +
reddish +, grayish +  and green +
pendent +  and erect +
2 +  and 20 +
palmate +  and pinnate +
linear;lanceolate or elliptic +
deciduous +
distinct +
subterminal +
filiform +
rough-thickened +
0.07 cm0.7 mm <br />7.0e-4 m <br /> (0.18 cm1.8 mm <br />0.0018 m <br />) +
Saxosae +, Ivesia sect. Saxosae +, Potentilla sect. Saxosae +, Potentilla subg. Purpusia +  and Undefined sect. Purpusia +
not fusiform +
stout;slender +
Ivesia paniculata +
Ivesia sect. Setosae +
species +
inconspicuous +
stipelike +, elongate +, less flat +  and conic or turbinate +
enlarged +
plant +  and matted +
glabrate +  and sparsely densely glandular-puberulent +