Flora of North America species comparison

usually ascending to erect, sometimes prostrate to decumbent or spreading, not flagelliform, not rooting at nodes (except P. verna), lateral to persistent basal rosettes, 0.1–2(–3) dm, lengths 1–3(–4) times basal leaves.

ascending to erect, 0.3–1.5(–2) dm, lengths 1–2 times basal leaves.

basal sometimes 2-ranked;

cauline 0–2(–3);

primary leaves ternate or palmate, (0.5–)1–12(–20) cm;

petiole: long hairs absent or spreading to ascending, weak to ± stiff, glands usually absent or sparse, sometimes abundant;

leaflets 3–7, at tip of leaf axis, overlapping or not, broadly oblanceolate or obtriangular to flabellate, margins flat to revolute, distal 1/4–3/4+ evenly to unevenly incised 1/4–1/2 to midvein, sometimes 3–5-lobed 1/2–3/4 to midvein as well, primary teeth (1–)2–5(–7) per side or per lobe, surfaces ± similar, abaxial pale to dark green, rarely grayish, brownish, or reddish, cottony hairs absent, adaxial green to dark green, rarely brownish or reddish, sometimes ± glaucous (P. grayi), long hairs (if present) soft to weak, sometimes stiff.

not in ranks, ternate, (1–)4–10(–15) cm;

stipules: apex acute to obtuse;

petiole (0.3–)2–11(–13) cm, long hairs abundant, ascending to spreading, 1–2.3 mm, soft, glands sparse to common;

leaflets 3, central obovate, 0.7–2.5 × 0.5–1.6 cm, petiolule 0–1 mm, margins revolute, not lobed, distal 1/2–2/3 evenly incised ± 1/3 to midvein, teeth 2–3(–4) per side, surfaces ± similar, green (paler abaxially), hairs common, 1–1.5 mm, glands common (sparser adaxially).

1–6(–12)-flowered, ± cymose, ± to very open, or solitary flowers.

1–3-flowered.

usually straight in fruit (often recurved in P. verna), (0–)0.2–3(–9) cm, proximal usually not much longer than distal (sometimes longer in fruit).

straight, 0.5–2 cm in flower, to 3.5 cm in fruit.

5-merous;

hypanthium 2–7 mm diam.;

petals pale to dark yellow, mostly ± obcordate (to orbiculate in P. elegans), (2–)3–10(–12) mm, usually longer than sepals, apex usually ± retuse;

stamens ca. 20;

styles subapical, columnar, filiform, or tapered, not, scarcely, or ± papillate-swollen in proximal 1/5–1/2, 0.8–2.5 mm.

epicalyx bractlets oblong, 3–7 × 1.2–2.5 mm, margins revolute;

hypanthium 4–6 mm diam.;

sepals 4–6(–7) mm, apex broadly acute to obtuse;

petals yellow, 9–12 × 8–10 mm;

filaments (2–)2.8–3.2 mm, anthers 0.5–0.8 mm;

carpels 40–50, styles filiform, not or scarcely papillate-swollen proximally, 1.7–2 mm.

± smooth.

1.3–1.5.

= 42, 56 (Russian Far East).