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 buenekeri Swales (1978)
 
Highslide JS
       
         

Habitat

Brazil
on flat rocks in the near of San Franzisko de Assis
about 124 mls (200 km) west of Cacapava

Description

forms dense clumps
flattened globular to short cylindrical
, dark dull green, to 5.9 in (15 cm) high and 3.9 in (10 cm) and more Ø
ribs mostly 5, broad roundish, between the areoles with slight notches
3–5 spines,
stiff, slight curved, bright yellow, become darker brown, to 1 in (2.5 cm) long
flowers bright peach pink to rosy, to 1.7 in (4.5 cm) long and 2.5 in (6.5 cm) Ø
fruits slightly cylindrical to ovate, green

Synonyms

Gymnocalycium horstii ssp. buenekeri (Swales) P. J. Braun & Hofacker (2002)
Gymnocalycium horstii
var. buenekeri Buining (1970) (nom. inval.)

CITES

Appendix II
 
Description of "Kakteen von A bis Z" by Walter Haage with courtesy by Kakteen-Haage made available.

 

 

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