Rosaceae A.L. de Jussieu
Rose family.
Rosaceae, rose family.
Vegetative morphology. Plants herbs, or shrubs; perennial herbs (if applicable); 1.5–35 cm high (in Arctic Islands); caespitose, or not caespitose. Taproot present, or absent. Caudex present, or absent. Ground-level or under-ground stems horizontal, or vertical and often branched; rhizomatous, or stoloniferous; elongate; 1–20 mm wide. Vegetative, aerial, stem a small transition zone between roots and basal leaves, or vegetative stem a small transition zone between roots and branches arising at ground-level, or aerial stems developed; aerial stems erect, or decumbent, or prostrate. Leaves in a basal tuft, or distributed along the stems; alternate; simple, or compound; existing for a single season or less, or marcescent. Stipules present (usually); scale-like; sheathing, or not sheathing; brown, or green, or colorless, or pink or reddish. Stipules glabrous, or hairy. Stipules glandular, or without glands; apex acuminate, or acute, or obtuse, or rounded. Petioles 1–80 mm long; with sessile glands, or without sessile glands; glabrous, or hairy; hairs less than the diameter of the petiole, or hairs more than the diameter of the petiole. Blades 4–50 mm long; 3–35 mm wide. Blades herbaceous, or leathery; flat, or revolute (if applicable). Blades adaxial surface glabrous, or glabrescent, or hairy. Blades abaxial surface dull; glabrous, or glabrescent, or hairy. Blade margins glabrous, or with non-glandular hairs. Leaflets 3–16; 5–30 mm long; 2–20 mm wide; oblong, or elliptic, or ovate, or obovate, or obtriangular. Leaflets veins conspicuous. Apical leaflet base distinctly stipitate, or not distinctly stipitate.
Reproductive morphology. Plants dioecious, or bisexual, or agamospermic. Flowering stems present. Flowering stems shorter than the leaves, or about as high as the leaves, or conspicuously taller than the leaves; with leaves, or without leaves; glabrous, or hairy. Flowering stem hairs simple, or glandular; shorter than the diameter of the flowering stem, or longer than the diameter of the flowering stem; white or translucent, or brown. Flowers solitary, or in inflorescences. Inflorescence cymose (usually), or head-like (if applicable); terminal, or axillary; dense, or diffuse. Pedicels absent, or present. Flowers per inflorescence 1–20; small, less than 5 mm in diameter or length, or medium-sized, 5–15 mm in diameter or length, or large, more than 15 mm in diameter or length. Epicalyx present, or absent. Epicalyx segments 2–9 mm long (if applicable); 0.5–4 mm wide (if applicable); shorter than the calyx segments, or equal in length to the calyx segments. Calyx sepals 4–10; free; 3–14 mm long; 1.5–8 mm wide. Calyx green, or brown, or purple, or red, or black; accrescent, or non-accrescent; with sessile glands, or without sessile glands; hairy; pilose, or villous, or woolly, or hairs short-silky, or hairs long-silky. Calyx hairs glandular, or non-glandular; white or translucent, or brown, or black. Calyx margins ciliate, or margins without cilia. Petals free; same length as the calyx, or longer than the calyx; 4–7(–11); green, or yellow, or pink; with contrasting markings, or without contrasting markings; obovate (usually), or elliptic, or ovate, or oblanceolate; unlobed, or shallowly lobed; 2.5–10(–18) mm long; (0.5–)2–12 mm wide. Stamens (5–)15–30(–60); filaments glabrous. Anthers yellow; ellipsoid, or subglobose, or triangular; 0.15–0.8 mm long. Gynoecia superior, or partly inferior. Carpels apocarpous; 7–50(–60). Styles 0.5–3(–6) mm long. Styles conical, or straight; basal portion smooth, or covered with short papillae, less than 0.1 mm high, or with hairs at the base. Stigmas plate shaped, or capitate, or receptive surface at the end of an otherwise unmodified style. Fruit without calyx persisting; fleshy; an aggregate of nutlets; ovoid; indehiscent. Fruit black, or brown, or red, or green at maturity, or golden brown, or straw coloured; glabrous, or hairy; surface venation reticulate, or appearing veinless. Styles modified and persisting (Dryas), or may persist until dehiscence but are not modified; becoming plumose (in Dryas; otherwise unmodified).
Chromosome information. 2n = 14, 18, 28, 35, 39, 42, 49, 64, 77.
Cite this publication as: ‘S.G. Aiken, M.J. Dallwitz, L.L. Consaul, C.L. McJannet, L.J. Gillespie, R.L. Boles, G.W. Argus, J.M. Gillett, P.J. Scott, R. Elven, M.C. LeBlanc, A.K. Brysting and H. Solstad. 1999 onwards. Flora of the Canadian Arctic Archipelago: Descriptions, Illustrations, Identification, and Information Retrieval. Version: 29th April 2003. http://www.mun.ca/biology/delta/arcticf/’. Dallwitz (1980) and Dallwitz, Paine and Zurcher (1993, 1995, 2000) should also be cited (see References).