Cannabaceae

Cannabaceae
Cannabis sativa
Scientific classification
Kingdom:Plantae
Clade:Angiosperms
Clade:Eudicots
Clade:Rosids
Order:Rosales
Family:Cannabaceae
Martinov[1][2]
Genera

See text

Synonyms[2]
  • Celtidaceae Endl.

Cannabaceae is a small family of flowering plants. As now circumscribed, the family includes about 170 species grouped in about 11 genera, including Cannabis (hemp, marijuana), Humulus (hops) and Celtis (hackberries). Celtis is by far the largest genus, containing about 100 species.[1]

Other than a shared evolutionary origin, members of the family have few common characteristics; some are trees (e.g. Celtis), others are herbaceous plants (e.g. Cannabis).

Description

Members of this family can be trees (e.g. Celtis), erect herbs (e.g. Cannabis), or twining herbs (e.g. Humulus).[1]

Leaves are often more or less palmately lobed or palmately compound and always bear stipules. Cystoliths are always present and some members of this family possess laticifers.

Cannabaceae are often dioecious (distinct male and female plants). The flowers are actinomorphic (radially symmetrical) and not showy, as these plants are pollinated by the wind. As an adaptation to this kind of pollination, the calyx is short and there is no corolla. Flowers are grouped to form cymes. In the dioecious plants the masculine inflorescences are long and look like panicles, while the feminine are shorter and bear fewer flowers. The pistil is made of two connate carpels, the usually superior ovary is unilocular; there is no fixed number of stamens.

The fruit can be an achene or a drupe.

Classification

Classification systems developed prior to the 1990s, such as those of Cronquist (1981) and Dahlgren (1989), typically recognized the order Urticales, which included the families Cannabaceae, Cecropiaceae, Celtidaceae, Moraceae, Ulmaceae and Urticaceae, as then circumscribed. Molecular data from 1990s onwards showed that these families were actually embedded within the order Rosales, so that from the first classification by the Angiosperm Phylogeny Group in 1998, they were placed in an expanded Rosales, forming a group which has been called "urticalean rosids".[2]

Phylogeny

Modern molecular phylogenetics suggest the following relationships:[2][3][4][5]

 

 

Moraceae (outgroup)

 
Cannabaceae

 

Aphananthe

 
 

 

Gironniera

 
 

 

Lozanella

 
 

 

 

Cannabis

 
 

Humulus

 
 
 

 

Celtis

 
 

 

 

Pteroceltis

 
 

Chaetachme

 
 
 

Trema (including Parasponia)

 
 
 
 
 
 
 
 

Genera

Hops (Humulus lupulus) with nearly mature fruits

Cannabaceae comprises the following genera:[5][6][7]

  • Aphananthe Planch. 1848 (5 spp.)
  • Cannabis L. 1753—Hemp (1 sp.)
  • Celtis L. 1753 (73–109 spp.)
  • Chaetachme Planch. 1848 (1 sp.)
  • Gironniera Gaudich. 1844 (6 spp.)
  • Humulus L. 1753—Hop (3 spp.)
  • Lozanella Greenm. 1906 [1905] (2 spp.)
  • Parasponia Miq. 1851 (5–10 spp.)
  • Pteroceltis Maxim. 1873 (1 sp.)
  • Trema Lour. 1790 (12–42 spp.)

Uses

Carbon dating has revealed that these plants may have been used for ritual/medicinal purposes in Xinjiang, China as early as 494 B.C.[8]

Hop (Humulus lupulus) has been the predominant bittering agent of beer for hundreds of years. The flowers' resins are responsible for beer's bitterness and their ability to extend shelf life due to some anti-microbial qualities. The young shoots are used as vegetable.

Some plants in the genus Cannabis are cultivated as hemp for the production of fiber, as a source of cheap oil, for their nutritious seeds, or their edible leaves. Others are cultivated for medical or recreational use as marijuana. Several selectively bred "strains" have been produced for both higher and lower yields of THC, other cannabinoids, as well as terpenes with desired flavors or aromas, such as blueberry, strawberry, or even citrus.

Many trees in the genus Celtis are grown for landscaping and ornamental purposes.

References

  1. 1 2 3 Stevens, P.F. (2001 onwards) "Cannabaceae", Angiosperm Phylogeny Website, retrieved 2014-02-25
  2. 1 2 3 4 Sytsma, Kenneth J.; Morawetz, Jeffery; Pires, J. Chris; Nepokroeff, Molly; Conti, Elena; Zjhra, Michelle; Hall, Jocelyn C. & Chase, Mark W. (2002), "Urticalean rosids: Circumscription, rosid ancestry, and phylogenetics based on rbcL, trnL–F, and ndhF sequences", Am J Bot, 89 (9): 1531–1546, doi:10.3732/ajb.89.9.1531, PMID 21665755
  3. ↑ Zavada MS, Kim M. (1996). "Phylogenetic analysis of Ulmaceae". Plant Syst Evol. 200 (1): 13–20. doi:10.1007/BF00984745.
  4. ↑ Yesson C, Russell SJ, Parrish T, Dalling JW, Garwood NC. (2004). "Phylogenetic framework for Trema (Celtidaceae)". Plant Syst Evol. 248 (1): 85–109. doi:10.1007/s00606-004-0186-3.
  5. 1 2 Yang M-Q, van Velzen R, Bakker FT, Sattarian A, Li D-Z, Yi T-S. (2013). "Molecular phylogenetics and character evolution of Cannabaceae". Taxon. 62 (3): 473–485. doi:10.12705/623.9.
  6. ↑ Stevens PF. (2017). "Cannabaceae Genera". Angiosperm Phylogeny Website. Retrieved 4 April 2017.
  7. ↑ "!!Cannabaceae Martinov". Tropicos. 2017. Retrieved 4 April 2017.
  8. ↑ Jiang, Hong-En; Li, Xiao; Zhao, You-Xing; Ferguson, David K.; Hueber, Francis; Bera, Subir; Wang, Yu-Fei; Zhao, Liang-Cheng; Liu, Chang-Jiang & Li, Cheng-Sin (December 2006), "A new insight into Cannabis sativa (Cannabaceae) utilization from 2500-year-old Yanghai Tombs, Xinjiang, China", Journal of Ethnopharmacology, 108 (3): 414–422, doi:10.1016/j.jep.2006.05.034, PMID 16879937, retrieved 2012-06-02
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