plumbago

Plumbago
Plumbago auriculata
Scientific classification
Kingdom: Plantae Division: Magnoliophyta Class: Magnoliopsida Order: Caryophyllales Family: Plumbaginaceae Genus: Plumbago L.
Species
See text

Plumbago is a genus of 10-20 species of flowering plants in the family Plumbaginaceae, native to warm temperate to tropical regions of the world. Common names include plumbago and leadwort (names which are also shared by the genus Ceratostigma). The name Plumbago is derived from Latin plumbum ("lead"), either from the lead-blue flower colour of some species (OED), or from the plant at one time being a supposed cure for lead poisoning (Huxley 1992).

Plumbago indica

Plumbago zeylanica

The species include herbaceous plants and shrubs growing to 0.5-2 m tall. The leaves are spirally arranged, simple, entire, 0.5-12 cm long, with a tapered base and often with a hairy margin. The flowers are white, blue, purple, red, or pink, with a tubular corolla with five petal-like lobes; they are produced in racemes.

The flower calyx has glandular hairs, which secrete a sticky mucilage that is capable of trapping and killing insects; it is unclear what the purpose of these hairs is; protection from pollination by way of "crawlers" (ants and other insects that typically do not transfer pollen between individual plants), or possible subcarnivory (Schlauer 1997).

Selected species

• Plumbago aphylla Bojer ex Boiss. Madagascar region.
• Plumbago auriculata Lam. (syn. P. capensis). Cape Leadwort. South Africa.
• Plumbago caerulea Humboldt, Bonpl. & Kunth (syn. P. coerulea). Western South America (northern Chile to Colombia).
• Plumbago europaea L. Common Leadwort. Mediterranean region to central Asia.
• Plumbago indica L. (syn. P. rosea). Southeast Asia.
• Plumbago pulchella Boiss. Mexico.
• Plumbago scandens L. Summer Snow Leadwort. Southern United States south to northern South America; sometimes included in P. zeylanica.
• Plumbago wissii
• Plumbago zeylanica L. ‘ilie‘e (Hawaiian islands) Southeast Asia south to Australia and into Pacific.

Gallery

Plumbago zeylanica at Ananthagiri Hills, in Rangareddy district of Andhra Pradesh, India.	Plumbago zeylanica at Ananthagiri Hills, in Rangareddy district of Andhra Pradesh, India.	Plumbago zeylanica at Ananthagiri Hills, in Rangareddy district of Andhra Pradesh, India.	Plumbago zeylanica at Ananthagiri Hills, in Rangareddy district of Andhra Pradesh, India.
Plumbago zeylanica at Ananthagiri Hills, in Rangareddy district of Andhra Pradesh, India.	Cape Leadwort (Plumbago auriculata)

References

• Germplasm Resources Information Network: Plumbago
• Flora of Chile: Plumbago (pdf file)
• Flora of China: Plumbago
• Flora of Ecuador: Plumbago
• Flora Europaea: Plumbago
• Flora of North America: Plumbago
• Flora of Pakistan: Plumbago
• Huxley, A., ed. (1992). New RHS Dictionary of Gardening. Macmillan.
• Schlauer, J. (1997). "New" data relating to the evolution and phylogeny of some carnivorous plant families. Carnivorous Plant Newsletter 26(2): 34-38 (available online).

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