Comarum L.

Herbs, perennial, 1–6 dm; stoloniferous and rhizomatous. Stems 1–several, decumbent to ascending aerial stems arising from horizontal ground-level stems, horizontal stems often rooting at nodes, sometimes floating, aerial stems glabrous proximally, finely appressed-hairy and often purplish-glandular distally. Leaves usually marcescent, cauline, alternate, odd-pinnate to subpalmate; stipules marcescent, partially to completely adnate to base of petiole, linear-lanceolate to elliptic-ovate, usually entire, sometimes serrate apically; petiole present, ?marcescent?; blade ± cordate in outline, 2–15 cm, foliaceous, leaflets (3–)5–7, lanceolate or oblanceolate to elliptic or obovate, margins flat, crenate to deeply serrate throughout or apically, venation pinnate, surfaces glabrous or finely appressed hairy. Inflorescences terminal, 1–10-flowered, flowers solitary or loosely cymose, hairy and often purplish-glandular; bracts present, leafy, smaller distally; bracteoles absent. Pedicels present, ?straight or nearly so?. Flowers 1–3 cm diam.; epicalyx bractlets 5; hypanthium slightly cupulate, 1–2 × (3–)4–8 mm, villous; sepals 5, spreading to reflexed, broadly ovate; petals 5, deep red to purple, rarely pink, ovate to spatulate, ?shorter than sepals?; stamens (15–)20–25(–30), shorter than or equal to petals, ?filaments filiform, not flattened, glabrous, thecae solitary, horseshoe-shaped, rimming broad connective, dehiscing by continuous, narrow, marginal slit?; torus hemispheric; carpels 30–100, glabrous, styles lateral to sub-basal, ?filiform?; ovule 1. Fruits aggregated achenes, individually deciduous (sometimes tardily so), 30–100, obliquely ovoid, (1–)1.3–1.6 mm, glabrous; ?torus enlarged, spongy, not fleshy, hairy?; hypanthium persistent; sepals persistent, reflexed; styles persistent, ?jointed?. x = 14.