Cannabaceae

Taxonomy

Family Name: Cannabaceae Martinov

Synonym(s): Celtidaceae Engl.; Lupulaceae Schultz Sch., nom. illeg.

Common Name(s): hemp family

*Number of genera/species: 8/100

List of genera records in GRIN-Global

Disseminule

fruit

Description

Fruit indehiscent, achene (Cannabis, Humulus) or drupe, 1.5–50 mm, ovoid to globose, terete to flattened in transection, usually unwinged (except in Pteroceltis, which has a pair of broad, woody, rounded wings), 1-seeded, enclosed by perianth. Pericarp glabrous or pubescent.

Achenes surrounded by one or two persistent bracts in addition to enclosed within perianth. Pericarp white, yellow, green, brown, shiny (Cannabis), crustaceous, and finely reticulate (Cannabis). Humulus achenes aggerated in cone-like structure, each enclosed in brownish or mottled perianth, and usually included in bracts.

Drupes styles persistent. Pericarp variously colored, dull, sometimes 3–5 angled, beaked or not, and fleshy (fibrous or succulent), rarely thin. Endocarp white, yellow, grayish brown, or reddish orange (Gironniera), 4–13 mm, and smooth or rugose or reticulately foveolate.

Seed globose or oblong, lenticular (achene) or terete or compressed (drupe) in transection, similar in length to fruit (achene) or endocarp (drupe). Achene seed coat adnate to pericarp. In drupes, seed coat brown, membranous, smooth or reticulate.

Embryo well developed, nearly filling seed cavity, peripheral, foliate. Humulus embryo flatly coiled. Cannabis horseshoe-shaped. In drupes, embryo arcuate, bent, or annular and cotyledons spatulate or investing and variously folded. In achenes, cotyledons circinate or convoluted. Endosperm scant and fleshy.

Identification features

Fruit
Type	achene, drupe
Size range	1.5–50 mm long
Shape(s)	elliptic, ovoid, lenticular, globose
Texture	achene - crustaceous drupe - fleshy to thin
Surface relief	achene - reticulate veined (Cannabis) drupe - smooth, sometimes rugose or lenticellate
Color(s)	achene - white, yellow, green, brown drupe - green, yellow, orange, red, reddish brown, brown, purplish black, black
Unique features	Small brown or yellowish, shiny achenes enclosed within persistent, thin, perianth and surrounded by bracts. In Humulus, achenes dispersed as within cone-like infructescence. Or, small, variously colored, dull, fleshy drupes. In Pteroceltis, drupe with two, broad, woody, rounded wings.
Seed
Size range	similar in size to fruit (achene) or endocarp (drupe)
Shape(s)	globose, oblong
Surface relief	smooth, reticulate
Color(s)	brown
Unique features	In drupes, bony endocarps hold a single seed with a curved embryo and scant endosperm.
Other
Embryo	well developed, nearly filling seed cavity, peripheral, foliate, arcuate, bent, horseshoe-shaped, or annular, cotyledons folded to circinate
Nutritive tissue	endosperm scant, fleshy

Distribution

Temperate and tropical regions worldwide

Distribution map courtesy of Angiosperm Phylogeny Website.

References

Backer 1951Backer 1951:
Backer CA. 1951. Cannabaceae. Flora Malesiana. Ser. 1, Spermatophyta 4(3): 222–224. https://www.biodiversitylibrary.org/page/40229357 ; Bingham et al. 2021+Bingham et al. 2021+:
Bingham MG, Willeman A, Wursten BT, Ballings P, and Hyde MA. 2021. Flora of Zambia. Accessed January 2021–March 2024. URL: https://www.zambiaflora.com; Flora of North America Editorial Committee 1993+Flora of North America Editorial Committee 1993+:
Flora of North America Editorial Committee, eds. 1993+. Flora of North America North of Mexico [Online]. 22+ vols. Flora of North America Association, New York and Oxford. Accessed January-March 2024. URL: http://beta.floranorthamerica.org.; Kirkbride et al. 2006Kirkbride et al. 2006:
Kirkbride JH, Jr, Gunn CR, and Dallwitz MJ. 2006. Family guide for fruits and seeds, vers. 1.0. Accessed September 2020-January 2022. URL: https://nt.ars-grin.gov/seedsfruits/keys/frsdfam/index.cfm .; Kubitzki et al. 1990+Kubitzki et al. 1990+:
Kubitzki K et al., eds. 1990+. The families and genera of vascular plants. 7+ vols. Berlin etc.; Nooteboom et al. 2021+Nooteboom et al. 2021+:
Nooteboom HP, de Wilde WJJO, Stevens PF, Coode MJE, and Saw LG. 2021+ Flora Malesiana Online. Accessed January 2021–March 2024. URL: https://portal.cybertaxonomy.org/flora-malesiana/; Takhtajan 2009Takhtajan 2009:
Takhtajan A. 2009. Flowering plants: Second edition. Springer Nature, Switzerland. 871 pp.; Tropicos.org 2021+Tropicos.org 2021+:
Tropicos.org. 2021+. Pakistan Plant Database. Missouri Botanical Garden. Accessed January 2021–March 2024. http://legacy.tropicos.org/Project/Pakistan; Tutin et al. 1964–1980Tutin et al. 1964–1980:
Tutin TG, Burges NA, Chater AO, Edmondson JR, Heywood VH, Moore DM, Valentine DH, Walters SM, and Webb DA (eds.) 1964–1980. Flora Europaea. 5 vols. Cambridge University Press, Cambridge UK. 2,524 pp.; Zhengyi et al. 2004+Zhengyi et al. 2004+:
Zhengyi W, Raven PH, and Deyuan H. 2004+. Flora of China [online]. 25 vols. Science Press, Beijing China & Missouri Botanical Garden, St. Louis USA. Accessed January–March 2024. http://flora.huh.harvard.edu/china/

*The number of genera and species is based on Christenhusz and Byng 2016Christenhusz and Byng 2016:
Christenhusz MJM and Byng JW. 2016. The number of known plant species in the world and its annual increase. Phytotaxa 261 (3): 201-217. https://doi.org/10.11646/phytotaxa.261.3.1, which may differ from the number of genera in GRIN-Global.