Gymnocalycium Pfeiffer ex Mittler (1844)

(Greek gymnos = naked, Greek kalyx = calyx)
naked flower calyx
because of the calyx without spines, bristles and hairs

usually flat globular, in age some thick columnar, very different sizes, simple or clumping
ribs 20 or less; spines adjacent or outspread, thin to very strong
flowers small short to large funnel shaped, often white or white with red center, however also yellow or red,
calyx bare and scaly; fruits and seeds very different

Highslide JS
 

Distribution

south America - Bolivia, Paraguay, south Brazil to Argentinia
almost complete south America eastern of the Cordilleras
steppes and mountains

Growth period

warm and part shady, avoid full sun, temporarily a location outdoor is possible
plants with stronger spines can get more sun
from early summer abundant watering, but standing moisture is to avoid
especially at warm weather not to sparse moisture

Winter period

bright and cool, not to dry, at 6–12°C (42–53°F), as possible not under 5°C (41°F)
mountain species occasionally also colder

Substrat

nutrient rich, very permeable to water with addition of peat
   
Gymnocalycium occultum Frič ex Schuetz (1962)
 
Highslide JS
  Highslide JS   Highslide JS
         

Field number

P131b - collected by Joerg and Brigitte Piltz

Habitat

Argentinia
Catamaraca - Sierra Ambato
in about 4265 ft (1300 m) altitude

Description

dark gray green to almost black, crown mostly with dense spination
ribs slight humpy
5 radial spines black, shiny, stiff

Comment

probably one of the forms of Gymnocalycium quehlianum
Synonyms Gymnocalycium occultum Frič ex Schuetz (1962) (nom. inval.)
Gymnocalycium stellatum
ssp. occultum Frič ex H. Till & W. Till (1996)
CITES Appendix II
 
Description of "Kakteen von A bis Z" by Walter Haage with courtesy by Kakteen-Haage made available.

 

 

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