Drymocallis lactea

(Greene) Rydberg in N. L. Britton et al.

in N. L. Britton et al., N. Amer. Fl. 22: 369. 1908.

Endemic
Basionym: Potentilla glandulosa var. lactea Greene Fl. Francisc., 65. 1891
Treatment appears in FNA Volume 9. Treatment on page 287. Mentioned on page 283, 284, 290.

Caudex branches short. Stems tufted, (0.3–) 1.5–6 (–6.5) dm; base 1–2.5 mm diam., not or sparsely, sometimes moderately, septate-glandular. Leaves usually sparsely to moderately hairy, sometimes glabrate; basal (2–) 5–20 (–30) cm, leaflet pairs (2–) 3–4 (–5); terminal leaflet broadly obovate to cuneate, 1–4 × 0.7–3.5 cm, teeth usually single, 4–10 (–14) per side, apex usually rounded to obtuse, rarely acute; cauline 1–2, reduced, leaflet pairs 2–3. Inflorescences (2–) 5–30 (–50) -flowered, not leafy, open, (1/6–) 1/5–1/2 (–4/5) of stem, narrow to wide, branch angles 10–40 (–50) °. Pedicels 2–10 (proximal to 30) mm, predominantly short-hairy, sometimes velutinous, not or sparsely, sometimes moderately, septate-glandular. Flowers opening widely; epicalyx bractlets linear-lanceolate to narrowly elliptic, 2–5 × 0.5–1.5 mm; sepals spreading, 3–8 (–9) mm, apex usually acute, sometimes obtuse and apiculate; petals ± overlapping, spreading, cream-white to bright-yellow, broadly obovate, (3–) 4–8 (–10) × 3–8 mm, usually longer than, rarely equal to, sepals; filaments 1–3 (–3.5) mm, anthers 0.6–1 mm; styles thickened, 1 mm. Achenes light-brown, 1 mm.

Discussion

Varieties 2 (2 in the flora).

Drymocallis lactea has had a well-established identity as Potentilla glandulosa var. (or subsp.) nevadensis; however, the epithet lactea has priority at species rank and avoids possible confusion with P. nevadensis Boissier. D. D. Keck (in J. Clausen et al. 1940) based his concept of P. glandulosa subsp. nevadensis on white-petaled plants with narrow inflorescences, the common form in the central Sierra Nevada and south. His map and annotations, however, include populations with yellow petals and widely branched inflorescences from northern California and adjacent Oregon. The two extremes merge in the northern Sierra Nevada, and populations in the North Coast Ranges of California also are problematic; the extremes are accordingly treated here as varieties of a single species. The inclusion by Keck of Washington in the species range might have been based on specimens here assigned to P. pseudorupestris.

Drymocallis lactea can be distinguished from sympatric species by its relatively large, overlapping petals, non-leafy inflorescences, and singly toothed leaflets. Pedicels and distal stems are usually densely short-hairy with relatively few or no glandular hairs (in contrast to D. pseudorupestris), and septate glands are usually absent from stem bases (in contrast to D. hansenii). The distinction between D. lactea and D. pseudorupestris breaks down at the margin of the species range in Nevada and Oregon.

Selected References

None.

Key

1 Inflorescences narrow, branch angles 10–20°; petals cream-white to pale yellowish; pedicels and stems not or sparsely septate-glandular. Drymocallis lactea var. lactea
1 Inflorescences wide, branch angles mostly 20–40°; petals usually pale to bright yellow; pedicels and stems sometimes moderately septate-glandular. Drymocallis lactea var. austiniae

"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.

... more about "Drymocallis lactea"
light-brown +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
obtuse;acute;acute;usually rounded;obtuse +
Barbara Ertter +
(Greene) Rydberg in N. L. Britton et al. +
compound +  and simple +
opposite +  and alternate +
20 cm200 mm <br />0.2 m <br /> (30 cm300 mm <br />0.3 m <br />) +
5 cm50 mm <br />0.05 m <br /> (20 cm200 mm <br />0.2 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
Potentilla glandulosa var. lactea +
oblanceolate-oblong +
1 cm10 mm <br />0.01 m <br /> (25 cm250 mm <br />0.25 m <br />) +
coriaceous +
reduced +
free +  and distinct +
Calif. +, Nev. +  and Oreg. +
not +  and aggregated +
0.2 cm2 mm <br />0.002 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
linear-lanceolate +  and narrowly elliptic +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
unisexual +  and bisexual +
not +  and aggregated +
deciduous +
less;10;80 +
0.07 cm0.7 mm <br />7.0e-4 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
open +, not leafy +  and (2-)5-30(-50)-flowered +
1/6 +  and 1/5-1/2-4/5 +
crassinucellate +
opposite +  and alternate +
marcescent +
winter-persistent +
glabrate +  and hairy +
overlapping +  and not confluent +
elliptic-ovate +  and flabellate or rhombic +
toothed +, or +, flat +, entire +  and more or less toothed +
inferior +  and superior +
clustered +, biseriate +  and superposed +
velutinous +  and short-hairy +
0.2 cm2 mm <br />0.002 m <br /> (1 cm10 mm <br />0.01 m <br />) +
overlapping +
0.8 cm8 mm <br />0.008 m <br /> (1 cm10 mm <br />0.01 m <br />) +
0 (?) +  and 4 (?) +
cream-white +  and bright-yellow +
free +  and distinct +
obovate +
0.3 cm3 mm <br />0.003 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
adnate +, free +, connate +  and distinct +
in N. L. Britton et al., N. Amer. Fl. +
not arillate +
0.8 cm8 mm <br />0.008 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
persistent +
free +  and distinct +
0.3 cm3 mm <br />0.003 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
free +  and distinct +
branched +  and simple +
stramineous +, reddish +  and green +
1 +  and 20 +
narrow +  and wide +
palmate +  and pinnate +
narrowly;broadly-triangular-ovate +
deciduous +
distinct +
fusiform +
1 cm10 mm <br />0.01 m <br /> (?) +
Closterostyles +, Potentilla sect. Closterostyles +, Potentilla subg. Closterostyles +  and Potentilla sect. Rupestres +
Drymocallis lactea +
Drymocallis +
species +
1 cm10 mm <br />0.01 m <br /> (4 cm40 mm <br />0.04 m <br />) +
broadly obovate +  and cuneate +
0.7 cm7 mm <br />0.007 m <br /> (3.5 cm35 mm <br />0.035 m <br />) +
horseshoe--shaped +
4 (?) +  and 10 (?) +
inconspicuous +
hemispheric +  and conic +
enlarged +
peglike-glandular +  and septate-glandular +