Ivesia muirii

A. Gray

Proc. Amer. Acad. Arts 8: 627. 1873.

Common names: Muir’s ivesia granite mousetail
Endemic
Synonyms: Potentilla muirii (A. Gray) Greene
Treatment appears in FNA Volume 9. Treatment on page 236. Mentioned on page 219, 230.

Plants silvery, usually ± rosetted; taproot stout, sometimes fleshy. Stems usually ± erect, sometimes nearly prostrate, 0.5–1.5 (–2) dm. Basal leaves very tightly cylindric (mousetail-like, with individual leaflets scarcely distinguishable), 2–5 (–10) cm; sheathing base densely strigose abaxially; petiole 0.2–0.8 (–1) cm, hairs 0.5–1.5 mm; leaflets 25–40 per side, 0.4–1 mm, densely sericeous, glands obscured, lobes 2–5, obovate or oval to orbiculate, apex not setose. Cauline leaves (0–) 1–2, paired if 2. Inflorescences 10–30-flowered, 1–2 (–3.5) cm diam.; glomerules usually 1. Pedicels 0.3–2 (–3.5) mm. Flowers 5–6 mm diam.; epicalyx bractlets oblong to obovate, 0.5–1 mm; hypanthium shallowly cupulate, 0.5–1 (–1.5) × 1.5–2.5 mm; sepals (1–) 1.5–2.5 mm, acute; petals yellow, linear to oblanceolate or narrowly oblong, 1–2 mm; stamens 5, filaments 0.3–0.6 mm, anthers yellow, 0.4–0.6 mm; carpels 1–4, styles 0.7–1.2 mm. Achenes grayish brown, mottled with red, 1.6–2 mm.


Phenology: Flowering summer.
Habitat: Dry rocky slopes, fellfields, mostly in alpine conifer woodlands and tundra
Elevation: 2900–4000 m

Discussion

Ivesia muirii is known from alpine areas in the Sierra Nevada. It is one of the more distinctive species of the genus, in its silvery mousetail-like leaves and usually tightly capitate inflorescences. Putative hybrids are known with I. lycopodioides (D. D. Keck 1938) and I. pygmaea (Center Basin area of Tulare County).

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 muirii"
not carunculate +
mottled with red +  and grayish brown +
1.6mm +  and 2mm +
longer than wide +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (0.06 cm0.6 mm <br />6.0e-4 m <br />) +
not setose +
acute;truncate rounded or emarginate +
Barbara Ertter +  and James L. Reveal +
A. Gray +
compound +  and simple +
opposite +  and alternate +
5 cm50 mm <br />0.05 m <br /> (10 cm100 mm <br />0.1 m <br />) +
2 cm20 mm <br />0.02 m <br /> (5 cm50 mm <br />0.05 m <br />) +
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 +
Muir’s ivesia +  and granite mousetail +
not +  and aggregated +
2900–4000 m +
oblong +  and obovate +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.06 cm0.6 mm <br />6.0e-4 m <br />) +
0.5 cm5 mm <br />0.005 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 rocky slopes, fellfields, mostly in alpine conifer woodlands and tundra +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
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 />) +
1.5mm;2.5mm +
1 cm10 mm <br />0.01 m <br /> (2 cm20 mm <br />0.02 m <br />) +
crassinucellate +
opposite +  and alternate +
winter-marcescent +
deciduous +  and persistent +
, +  and distinct +
not +  and distinguishable +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
oval +  and orbiculate +
verticillate +
toothed +, unlobed +  and lobed +
inferior +  and superior +
clustered +, biseriate +  and superposed +
0.2 cm2 mm <br />0.002 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
0 (?) +  and 4 (?) +
free +  and distinct +
linear;oblanceolate or narrowly oblong +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
0.8 cm8 mm <br />0.008 m <br /> (1 cm10 mm <br />0.01 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
Flowering summer. +
adnate +, free +, connate +  and distinct +
Proc. Amer. Acad. Arts +
not arillate +
0.1 cm1 mm <br />0.001 m <br /> (0.15 cm1.5 mm <br />0.0015 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 />) +
free +  and distinct +
branched +  and simple +
reddish +, grayish +  and green +
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 /> (0.12 cm1.2 mm <br />0.0012 m <br />) +
Potentilla muirii +
slender;stout +
Ivesia muirii +
Ivesia sect. Ivesia +
species +
inconspicuous +
stipelike +, elongate +, less flat +  and conic or turbinate +
enlarged +
glabrate +  and sparsely densely glandular-puberulent +