Potentilla sect. Rubrae

(Rydberg) O. Stevens in N. L. Britton et al.

in N. L. Britton et al., N. Amer. Fl. 22(7): 11. 1959.

Basionym: Rubrae Rydberg in N. L. Britton et al., N. Amer. Fl. 22(4): 293, 323. 1906
Synonyms: Potentilla sect. Haematochrus (Rydberg) Schiman-Czeika Haematochrus Rydberg Potentilla sect. Haematochrus (Rydberg) B. C. Johnston
Treatment appears in FNA Volume 9. Treatment on page 148. Mentioned on page 124, 244, 301.

Perennials, ± tufted, not stoloniferous; taproots not fleshy-thickened; vestiture of long, short, crisped, and/or cottony hairs, glands sparse to abundant, rarely reddish. Stems ascending to nearly erect, not flagelliform, not rooting at nodes, lateral to persistent basal rosettes, (2–) 3–7 (–10) dm, lengths (2–) 3–5 times basal leaves. Leaves: basal not 2-ranked; cauline 1–3; primary leaves palmate to ± subpalmate, (2–) 4–15 (–30) cm; petiole: long hairs spreading to weakly appressed, weak to ± stiff, glands sparse to abundant, rarely absent; leaflets 5–7, on tip or less than distal 1/10 of leaf axis, ± overlapping or not, oblanceolate or oblong to elliptic or obovate, margins flat, distal 1/2 to whole length evenly incised 1/5–1/4 or less to midvein, teeth (0–) 4–15 (–19) per side, surfaces similar or slightly to strongly dissimilar, abaxial green to white, cottony hairs absent or sparse to dense, adaxial green, not glaucous, long hairs weak to stiff. Inflorescences (4–) 10–40 (–70) -flowered, cymose, open. Pedicels straight in fruit, 0.3–4 cm, proximal ± longer than distal. Flowers 5-merous; hypanthium 4–6 mm diam.; petals dark reddish to reddish orange, ± obcordate, (3.5–) 5–10 mm, equal to or longer than sepals, apex retuse; stamens 20–30; styles subapical, tapered-filiform, papillate-swollen in proximal 1/5, 2–3.5 mm or less. Achenes ± rugose.

Distribution

sw United States, Mexico, Asia

Discussion

Species 9 (2 in the flora).

Red petals distinguish species of sect. Rubrae from the remaining species assigned here to Potentilla. Most species in the section occur in Mexico. As traditionally defined, sect. Rubrae also includes the southeastern Asian species P. atrosanguinea Loddiges, G. Loddiges & W. Loddiges (3 leaflets), P. argyrophylla Wallich ex Lehmann (3 leaflets), and P. nepalensis Hooker (5 leaflets). The first is available in the horticultural trade and was reported in a strawberry field in New Brunswick, Canada (B. Boivin 1966b; H. J. Scoggan 1978–1979, part 3); it did not become naturalized. The name P. argyrophylla var. atrosanguinea (Loddiges, G. Loddiges & W. Loddiges) Hooker f., used in the Flora of China (Li C.-L. et al. 2003c) is incorrect; P. argyophylla (1831) is a name later than P. atrosanguinea (1823).

Selected References

None.

Key

1 Basal leaves palmate; leaflets 5(–7), distal 3/4 to whole margin incised, surfaces slightly to strongly dissimilar; petals ± dark reddish throughout; cauline leaves: stipules usually toothed, sometimes entire; widespread, Arizona, New Mexico. Potentilla thurberi
1 Basal leaves usually ± subpalmate, sometimes palmate; leaflets (5–)7, distal 1/2–3/4 (sometimes nearly whole) margin incised, surfaces ± similar; petals dark reddish proximally, reddish orange distally; cauline leaves: stipules usually entire; Coconino County, Arizona. Potentilla sanguinea

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... more about "Potentilla sect. Rubrae"
green +  and white +
Barbara Ertter +  and James L. Reveal +
(Rydberg) O. Stevens in N. L. Britton et al. +
compound +  and simple +
Rubrae +
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 />) +
coriaceous +
reduced +
free +  and distinct +
hairy +  and glabrous +
sw United States +, Mexico +  and Asia +
not +  and aggregated +
0.8 cm8 mm <br />0.008 m <br /> (2 cm20 mm <br />0.02 m <br />) +
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 />) +
sparse;abundant +
crisped +
stoloniferous +  and short-rhizomatous +
straight +
weak +  and stiff +
spreading +  and weakly appressed +
sparse to dense +
crisped +
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 />) +
0.4 cm4 mm <br />0.004 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
0.5mm;2.5mm +
turbinate +, patelliform +  and cupulate +
open +, cymose +  and (4-)10-40(-70)-flowered +
crassinucellate +
bipinnate +, odd-pinnate +, subpalmate +, palmate +  and ternate +
opposite +  and alternate +
marcescent +
well-developed +
persistent +
cauline +  and basal +
reduced +
not +  and overlapping +
oblong +  and elliptic or obovate +
linear +  and oblanceolate +
palmate +  and pinnate +
revolute toothed +  and divided +
inferior +  and superior +
clustered +, biseriate +  and superposed +
0.3 cm3 mm <br />0.003 m <br /> (4 cm40 mm <br />0.04 m <br />) +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
dark reddish +  and reddish orange +
free +  and distinct +
obcordate +
0.5 cm5 mm <br />0.005 m <br /> (1 cm10 mm <br />0.01 m <br />) +
adnate +, free +, connate +  and distinct +
palmate +  and more or less subpalmate +
15 cm150 mm <br />0.15 m <br /> (30 cm300 mm <br />0.3 m <br />) +
4 cm40 mm <br />0.04 m <br /> (15 cm150 mm <br />0.15 m <br />) +
in N. L. Britton et al., N. Amer. Fl. +
not arillate +
persistent +
free +  and distinct +
erect +  and spreading +
lanceolate +  and broadly ovate or deltate +
free +  and distinct +
not rooting +
reddish +  and green +
ascending +  and nearly erect +
1 +  and many +
not flagelliform +
palmate +  and pinnate +
linear;ovate +
deciduous +
distinct +
subapical +
papillate-swollen +  and tapered-filiform +
rough-thickened +
Potentilla sect. Haematochrus +  and Haematochrus +
not fleshy-thickened +
Potentilla sect. Rubrae +
Potentilla +
section +
4 (?) +  and 15 (?) +
inconspicuous +
enlarged +
biennial +, annual +  and perennial +
herb +  and matted +