This fiercely spined species has very fragrant flowers (like Lemon flowers)
that open up in the evening and close up early the next morning.

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Subfamily: Cactoideae tribe: Trichocereeae.

Origin:  Brazil (Minas Gerais)
 
Habitat: This cactus grows in the shade of trees.

Conservation status: Listed in CITES appendix 1.These species are threatened with extinction.

Synonyms:  

• Discocactus placentiformis (Lehm.)K. Schum
• Cactus placentiformis
• Discocactus alteolens Lemoine ex A.Dietr.
• Discocactus latispinus Buining & Brederoo
• Discocactus milticolorispinus P.J.Braun & Brederoo
• Discocactus pseudolatispinus Diers & Esteves
• Discocactus pugionacanthus Buining & Brederoo
• Discocactus pulvinicapitatus Buining & Brederoo
• Discocactus tricornis Monv. ex Pfeiff. & Otto
• Melocactus besleri

Cultivation: Collectors consider this cactus genus from South America to be rarities as they are not the easiest plant to keep happy. it is rather difficult to grow and frost tender, should be kept at above 15° C if grown on its own roots (8°C if grafted) need full sun or afternoon shade. Young seedlings are generally grafted because they are slow growing and very rot prone when kept on their own roots and though they can’t endure long stretches of total dryness, too much water will rot them, as their weak root systems tend to be inefficient at sucking up water from wet soil. They generally resent being repotted and can take a long time to establish.

Propagation: Seed. Young seedlings are often grafted on a low stock to keep the plant in a good shape.