Potentilla rhyolitica var. rhyolitica

Treatment appears in FNA Volume 9. Treatment on page 186.

Stems 0.3–2 dm. Leaves gray-green; long hairs of petioles 1 (–2) mm; leaflets: hairs usually dense, sometimes common. Flowers 2–10; filaments 1.5–2.5 mm; carpels 5–15, styles 2–2.5 mm. Achenes 1.5 mm, smooth to lightly rugose.


Phenology: Flowering Apr–Jun.
Habitat: Rhyolite and quartzite outcrops, in open pine forests
Elevation: 2600–2900 m

Discussion

Of conservation concern.

Variety rhyolitica forms dense tufts in outcrops near the summits of the Huachuca and Santa Rita ranges (Cochise and Santa Cruz counties). The name Potentilla viscidula (Rydberg) Rydberg (= P. wheeleri var. viscidula Rydberg) was misapplied to these plants by T. H. Kearney and R. H. Peebles (1951); that name has been lectotypified on the hybrid of P. rhyolitica and P. subviscosa (B. Ertter 2007c).

Selected References

None.

Lower Taxa

None.

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

smooth +  and lightly rugose +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
Barbara Ertter +
Ertter +
palmate +  and ternate +
opposite +  and alternate +
8 cm80 mm <br />0.08 m <br /> (11 cm110 mm <br />0.11 m <br />) +
2 cm20 mm <br />0.02 m <br /> (8 cm80 mm <br />0.08 m <br />) +
Subviscosae +
25 cm250 mm <br />0.25 m <br /> (30 cm300 mm <br />0.3 m <br />) +
less cordate or reniform +  and narrowly elliptic +
0.5 cm5 mm <br />0.005 m <br /> (25 cm250 mm <br />0.25 m <br />) +
reduced +
free +  and distinct +
hairy +  and glabrous +
1 cm10 mm <br />0.01 m <br /> (3 cm30 mm <br />0.03 m <br />) +
1/3 +, 1/2 +  and 2/3 +
obovate +  and broadly elliptic +
0.8 cm8 mm <br />0.008 m <br /> (1.8 cm18 mm <br />0.018 m <br />) +
not +  and aggregated +
2600–2900 m +
0.2 cm2 mm <br />0.002 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
1 cm10 mm <br />0.01 m <br /> (?) +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
5-merous +, racemiform +, open +, cymose +  and 2-10(-20)-flowered +
0.8 cm8 mm <br />0.008 m <br /> (2 cm20 mm <br />0.02 m <br />) +
2 +  and 10 +
unisexual +  and bisexual +
not +  and aggregated +
deciduous +
on style scar +, hairy +  and glabrous +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.26 cm2.6 mm <br />0.0026 m <br />) +
Rhyolite and quartzite outcrops, in open pine forests +
stoloniferous +  and short-rhizomatous +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
straight +
weak +  and more or less stiff +
spreading +  and loosely appressed +
crisped +
1 cm10 mm <br />0.01 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
differentiated +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
0.7 cm7 mm <br />0.007 m <br /> (1 cm10 mm <br />0.01 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
crassinucellate +
bipinnate +, odd-pinnate +, subpalmate +, palmate +  and ternate +
opposite +  and alternate +
gray-green +
marcescent +
well-developed +
persistent +
cauline +  and basal +
reduced +
separate +  and slightly overlapping +
orbiculate +, elliptic +  and broadly obovate or cuneate +
linear +  and oblanceolate +
palmate +  and pinnate +
1/5 +  and 3/4 +
inferior +  and superior +
clustered +, biseriate +  and superposed +
1 cm10 mm <br />0.01 m <br /> (2 cm20 mm <br />0.02 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (1 cm10 mm <br />0.01 m <br />) +
0.7 cm7 mm <br />0.007 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
free +  and distinct +
0.3 cm3 mm <br />0.003 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
6 cm60 mm <br />0.06 m <br /> (8 cm80 mm <br />0.08 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
1 cm10 mm <br />0.01 m <br /> (6 cm60 mm <br />0.06 m <br />) +
Flowering Apr–Jun. +
adnate +, free +, connate +  and distinct +
palmate +  and ternate +
10 cm100 mm <br />0.1 m <br /> (18 cm180 mm <br />0.18 m <br />) +
2 cm20 mm <br />0.02 m <br /> (10 cm100 mm <br />0.1 m <br />) +
usually not much longer +
J. Bot. Res. Inst. Texas +
not arillate +
persistent +
free +  and distinct +
erect +  and spreading +
lanceolate +  and broadly ovate or deltate +
0.3 cm3 mm <br />0.003 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
Conservation concern +  and Endemic +
free +  and distinct +
not rooting +
reddish +  and green +
1-3(-5) times basal leaves +
prostrate to decumbent +
1 +  and many +
not flagelliform +
palmate +  and pinnate +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
deciduous +
distinct +
subapical +
papillate-swollen +, tapered-columnar +  and filiform +
rough-thickened +
0.2 cm2 mm <br />0.002 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
green +  and gray-green +
not glaucous +
Potentilla rhyolitica var. rhyolitica +
Potentilla rhyolitica +
variety +
2 +  and 3 +
inconspicuous +
enlarged +
tufted +  and rosetted +
biennial +, annual +  and perennial +
herb +  and matted +