Matucana madisoniorum

Matucana madisoniorum usually grows solitary and only rarely sprouts with flattened, spherical to broadly columnar, cloudy grey-green shoots and reaches a height of up to 15 centimeters with a diameter of 10 centimeters. There are seven to twelve flat and broad transversely furrowed ribs. The up to five blackish-brown, curved, flexible and slightly falling spines, which can also be absent, turn gray with age. They are up to 3 centimeters long.

The narrow, funnel-shaped, slightly crooked, orange-red flowers are 8 to 10 centimeters long and have a diameter of 4 to 5.5 centimeters. The spherical, hairy fruits reach a diameter of up to 2 centimeters.[3]

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  Adult plant
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  Blooming size plant
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  crown closeup
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  Flower closeup
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  White flower form

Matucana madisoniorum is found in the Peruvian Amazon region northeast of the city of Bagua in the valley of the Río Marañón at altitudes of 400 to 1000 meters.

The first description as Borzicactus madisoniorum was in 1963 by Paul Clifford Hutchison.[4] The specific epithet madisoniorum honors US attorney Marshall Pierce Madison (1895–1977), his wife Elena Eyre Madison, and the Madison Fund in San Francisco for supporting the University of California Botanical Garden. Gordon Douglas Rowley placed the species in the genus Matucana in 1973. Other nomenclature synonyms are Submatucana madisoniorum (Hutchison) Backeb. (1966), Loxanthocereus madisoniorum (Hutchison) Buxb. (1974), Eomatucana madisoniorum (Hutchison) F.Ritter (1981) and Anhaloniopsis madisoniorum (Hutchison) Mottram (2014).

• Media related to Matucana madisoniorum at Wikimedia Commons
• Data related to Matucana madisoniorum at Wikispecies