Cephalanthus Explained

Cephalanthus is a genus of flowering plants in the family Rubiaceae. There are about six species that are commonly known as buttonbush.^{[1] [2]}

Description

They are shrubs or small trees growing to 5- tall. The leaves are simple, arranged in opposite pairs or whorls of three. The flowers form a dense globular inflorescence.

Distribution and habitat

Cephalanthus occidentalis is native to the eastern United States and Canada. The others occur in tropical regions of the Americas, Africa and Asia.^[3] Two species are known in cultivation.^[4]

Systematics

Cephalanthus was named by Linnaeus in Species Plantarum in 1753.^[5] The generic name is derived from the Ancient Greek words κέφαλη (kephale), meaning "head", and ἄνθος (anthos), meaning "flower".^[6]

Taxonomy

Cephalanthus is the most basal genus in the tribe Naucleeae.^[7] Some authors have segregated it into its own monotypic tribe.^[8] The type species is Cephalanthus occidentalis.^[9]

Species

• Cephalanthus angustifolius Lour. - Laos, Cambodia, Vietnam
• Cephalanthus glabratus (Spreng.) K.Schum. - sarandí - Brazil, Argentina, Paraguay, Uruguay
• Cephalanthus natalensis Oliv. - Tanzania, Malawi, Zambia, Lesotho, Eswatini, South Africa
• Cephalanthus occidentalis L. - button-willow, common buttonbush, honey-bells - Cuba, eastern Canada, eastern, central and southern United States, California, Arizona, New Mexico
• Cephalanthus salicifolius Humb. & Bonpl. - Mexican buttonbush, willowleaf buttonbush - Mexico, Honduras, extreme southern tip of Texas
• Cephalanthus tetrandrus (Roxb.) Ridsdale & Bakh.f.^{[10] [11]} - tropical Asia from India to China and Thailand

Fossil record

16 fossil mericarps of †Chephalanthus pusillus have been described from middle Miocene strata of the Fasterholt area near Silkeborg in Central Jutland, Denmark.^[12]

External links

• Kew World Checklist of Selected Plant Families, Cephalanthus
• USDA PLANTS, Cephalanthus
• Flora of Taiwan, Cephalanthus

Notes and References

1. http://www.theplantlist.org/browse/A/Rubiaceae/Cephalanthus The Plant List, Cephalanthus
2. http://www.efloras.org/florataxon.aspx?flora_id=2&taxon_id=106077 Flora of China, Cephalanthus
3. Book: Mabberley DJ. 2008. Mabberley's Plant Book. 3rd. Cambridge University Press. 978-0-521-82071-4.
4. Huxley AJ et al. (eds.) The New Royal Horticultural Society Dictionary of Gardening. The Macmillan Press Limited, London; The Stockton Press, New York. 1992.
5. Linnaeus, C. Cephalanthus. Species Plantarum. 1753. 1: 95
6. Book: Quattrocchi, U.. 2000. CRC World Dictionary of Plant Names. 1. 476. CRC Press. Boca Raton, New York, Washington DC, London. 978-0-8493-2675-2.
7. Manns, U. and B. Bremer. 2010. Towards a better understanding of intertribal relationships and stable tribal delimitations within Cinchonoideae s.s. (Rubiaceae). Molecular Phylogenetics and Evolution 56(1), 21-39.
8. Ridsdale CE. 1976. A revision of the tribe Cephalantheae (Rubiaceae). Blumea. 23. 1. 177–88.
9. http://www.botany.si.edu/ing/INGsearch.cfm?searchword=Cephalanthus Cephalanthus.
10. Web site: Cephalanthus tetrandrus (Roxb.) Ridsdale & Bakh.f.. June 2023. WFO Plant list. 18 August 2023.
11. Web site: Cephalanthus tetrandrus (Roxb.) Ridsdale & Bakh.f.. Plants of the World Online. Royal Botanic Gardens, Kew. 18 August 2023.
12. Angiosperm Fruits and Seeds from the Middle Miocene of Jutland (Denmark) by Else Marie Friis, The Royal Danish Academy of Sciences and Letters 24:3, 1985