Rosa sect. Minutifoliae

Crépin

J. Roy. Hort. Soc. 11: 226. 1889.

Treatment appears in FNA Volume 9. Treatment on page 79. Mentioned on page 77.

Shrubs, forming dense thickets, xerophytic; rhizomatous. Stems erect, rarely arching, 2.5–12(–15) dm; distal branches densely pubescent or glabrous, with or without stellate hairs; prickles erect, rarely curved, infrastipular prickles present, mixed with internodal prickles and aciculi. Leaves deciduous, 1.5–3 × 1.5–2.5 cm; stipule margins entire or dentate, glandular or eglandular, auricles flared; leaflets 3–7, terminal: petiolule 0.5–4 mm, blade oval, suborbiculate, obovate, or deltate, 6–18 × 4–13 mm, abaxial surfaces usually pubescent or tomentulose, rarely glabrous. Inflorescences 1(–3)-flowered. Pedicels erect, stout, 2–16 mm, mostly setose, often pubescent, rarely glabrous; bracts 0 or 1 or 2, margins serrate to deeply incised. Flowers 2.5–5 cm; hypanthium thick-walled, setose or not; sepals ovate-lanceolate, 8–20 × (1–)2–5 mm, margins pinnatifid, abaxial surfaces glabrous or pubescent, sessile- or stipitate-glandular, sometimes eglandular; petals single, pink to rose pink, sometimes white; carpels 10–110, styles free, stylar orifice 2–5 mm diam., rims 0.5–1 mm wide, hypanthial disc absent. Hips dull red to dark reddish purple, subglobose or cupulate, 5–13(–18) × 5–16(–18) mm, hard, leathery, pubescent or glabrous, setose, stipitate-glandular or eglandular; sepals persistent, erect. Achenes basal.

Distribution

sw, sc United States, nw Mexico.

Discussion

Species 2 (2 in the flora).

Selected References

None.

Key

1 Leaflets 5–7, terminal blades 3–7 × 2–6 mm; bracts 1 or 2; flowers 2.5–3(–4) cm diam.; hypanthia subglobose to globose, densely pubescent and setose; distal branches pubescent or glabrous, without stellate hairs; sepals 8–12 × 2–4 mm, abaxial surfaces pubescent; hips eglandular, densely setose. Rosa minutifolia
1 Leaflets 3–5, terminal blades 8–18 × 5–13 mm; bracts 0; flowers 4–5 cm diam.; hypanthia cupulate, puberulent or glabrous; distal branches densely pubescent, with or without stellate hairs; sepals 12–20 × 4–5 mm, abaxial surfaces glabrous, sometimes puberulent; hips stipitate-glandular, densely or sparsely setose. Rosa stellata