Rosaceae

Taxonomy

Family name: Rosaceae Jussieu

Synonym(s): Agrimoniaceae Gray; Alchemillaceae Martinov; Amygdalaceae Marquis, nom. cons.; Cercocarpaceae J. Agardh; Coleogynaceae J. Agardh; Dryadaceae Gray; Fragariaceae Nestl.; Lindleyaceae J. Agardh; Malaceae Small, nom. cons.; Neilliaceae Miq.; Potentillaceae Bercht. & J. Presl; Prunaceae Martinov; Rhodotypaceae J. Agardh; Sanguisorbaceae Bercht. & J. Presl; Spiraeaceae Bertuch; Ulmariaceae Gray

Common name(s): rose family

*Number of genera/species: 111/2,950

List of genera records in GRIN-Global

Disseminule

fruit, incomplete fruit with epicarp and mesocarp absent and endocarp exposed (pyrene), or seed

Description

Fruit usually indehiscent, achenes or drupes, often aggregated, pomes, or dehiscent follicles, often aggregated, or rarely capsules, 1–150 mm long, globose to angled, usually terete, sometimes compressed (Potentilla, Rhodotypos) or laterally flattened (Holodiscus) in transection, styles often persistent, forming short or long beaks (long, terminal, hairy styles in Dryas and Geum). Fruit sometimes winged (Amygdaloideae), if winged, wings at both ends or only a apex or may appear caudate at both ends. Fruit 1-seeded (achene, drupelet), usually few to less than 20-seeded (sometimes many-seeded in pomes), often enclosed by hypanthium and crowned by persistent calyx, or subtended by persistent calyx. Hypanthium, if present, fused to fruit wall, fleshy, and cupular or narrow-mouthed. Rarely fruit attached to enlarged, fleshy or not fleshy torus. Pericarp black, blue or purplish black, purple, brown, green, red, orange, yellow, or rarely white (Osteomeles), shiny or dull, thick or thin walled, bony, cartilaginous, leathery, fibrous, woody, or fleshy, sometimes gritty, glabrous or pubescent, if pubescent often densely so with short, white hairs, rarely with long-stalked glands (Neillia spp.). Pericarp (or hypanthium) smooth or ridged, ribbed, wrinkled, punctate, or with bristles, spines, or protuberances. In pomes, the fleshy layer is derived from hypanthial and/or carpellary tissue and may have sclereids (gritty) or not and have large pigment cells or not. A pome’s endocarp may be firm-membranous, cartilaginous, leathery, bony or slightly woody.

Fruit type by subfamily

Amygdaloideae: achene, nutlet, or follicle, often aggregated, or pome, drupe, or capsule

Dryadoideae: achene or head of achenes (with long persistent, terminal, hairy styles, Dryas)

Rosoideae: achene, 1 or 2 or numerous (Rosa) enclosed in hypanthium (with bristles Agrimonia, with spines Acaena, red and fleshy Aremonia, Sarcopoterium). Or folliclelike achene (Filipendula, indehiscent), head of achenes (with long persistent, terminal, hairy styles, Geum), or aggregated nutlets (Leucosidea) or drupelets (Rubus)

Seed globose to pyriform, rarely reniform (Potentilla), sometimes with fold between cotyledons and hypocotyl-radicle or notched, 1.5–5 mm long. Raphe sometimes conspicuous. Aril or arillike structure usually absent, except for caruncle on Physocarpus seeds. Seed coat black or brown, glabrous, usually thin, firm, membranous, or leathery, smooth or ridged, striate, pitted, papillate, punctate, or wrinkled. Margins with markedly different tissue than rest of seed coat.

Embryo well developed, completely to nearly completely filling seed coat, axile and centric, foliate or linear, straight, bent, or curved. Cotyledons thin, flat or once-folded, rarely convolute, with entire apices. Endosperm usually thin, sometimes absent, rarely copious (Kerria, Neillia, Physocarpus), if present fleshy and smooth. Perisperm present.

Habitat and crop association

Noxious Weeds: USA Federal Noxious Weed List, terrestrial, Rubus fruticosus Linnaeus agg. (complex), Rubus moluccanus Linnaeus.

More about these species on the Federal Noxious Weed Disseminules of the US ID tool.

Identification features

Fruit
Type	achene, follicle, drupe, pome, rarely capsule
Size range	1–150 mm long
Shape(s)	globose, cymbiform, ellipsoid, oblong, ovoid, conical, pyriform, boat-shaped, lanceoloid, falcate, reniform, or 4-angled
Texture	thick or thin walled, bony, cartilaginous, leathery, fibrous, woody, fleshy, sometimes gritty
Surface relief	smooth, ridged, ribbed, wrinkled, punctate, or with bristles, spines, or protuberances
Color(s)	black, blue or purplish black, purple, brown, green, red, orange, yellow, rarely white
Unique features	Five types of fruits. 1) Small achenes aggregated or not, with persistent styles, which are often hooked and/or hairy. Infrequently achenes attached to fleshy central tissue. 2) Aggregate of drupes. 3) Achenes surrounded by green tissue. 4) Flesh fruit with stone surrounding seeds. 5) Fruit with grainy fleshy pulp surrounding seeds.
Seed
Size range	1.5–5 mm long
Shape(s)	globose, ellipsoid, linear, fusiform, oblong, ovoid, lanceoloid, pyriform,  rarely reniform
Surface relief	smooth, ridged, striate, pitted papillate, punctate, wrinkled
Color(s)	black, brown
Other
Embryo	well developed, completely to nearly completely filling seed coat, axile and centric, foliate or linear, straight, bent, or curved. Cotyledons thin, flat or once-folded, rarely convolute, with entire apices.
Nutritive tissue	endosperm usually thin, sometimes absent, rarely copious (Kerria, Neillia, Physocarpus), if present fleshy and smooth. Perisperm present.

Distribution

Nearly worldwide, diverse in subtropics and temperate regions of the Northern Hemisphere.

Distribution map courtesy of Angiosperm Phylogeny Website.

References

Hyde et al. 2021c+; Flora of North America Editorial Committee 1993+; Kirkbride et al. 2006; Kubitzki et al. 1990+; Liu et al. 2019; Nooteboom et al. 2021+; Noxious Weed Regulations 2020; Phipps 1992; Takhtajan 2009; Tutin et al. 1968; USDA 1980

*The number of genera and species is based on Christenhusz and Byng 2016, which may differ from the number of genera in GRIN-Global.