Copiapoa marginata
(Syn: Copiapoa calderana)

Copiapoa marginata.

Description: Plants, solitary or growing in clusters of 2 to 9, usually erect, but when old spreading with ascending tips.
Stem: Subcylindric or ellipsoid (narrowed towards the top and the base), ashen-green, with domed crown, woolly at the top.  Up to 18 cm tall, 8-12 cm wide.
Ribs: 8 to 12 (usually 10), separated by broad intervals, slightly convex, rounded off towards the top but flattened nearer the base, with very obtuse grooves in between.
Areoles: Broad, almost round, entirely confluent (flowing together), convex, young areoles and tops of flowering plants filled with tufts of soft brown or black felted wool;
Radial spines: 5-7 spreading outwards, more or less standing out in a radiating manner, subulate, stout, rigid, straight, at first chocolate brown, afterwards becoming greyish; The lower-most, more strongly growing, are all stiff and straight
Central spines: Single, the longer one 3 cm. long and standing straight out.  Under the magnifying glass they are seen to be marked with faint lines.
Flowers: Yellow, 2.5 cm. long with outer petals upright, acute-lanceolate, pointed and of a reddish colour, inner petals upright, obtuse, with a very short terminal point.  The crowded filaments as well as the anthers are yellowish; the style is thick and hollow, the eleven stigma lobes yellow.
Blooming season: Spring and summer
Fruit: Naked, small, 8 mm. long;
Seeds: Black, shining.
Note: This appears to be a variable species.

Scientific name:   Copiapoa marginata  (Salm-Dyck.) BR. & R. 1922

Origin:  Chile, Prov. Atacama, Coastal hills from Antofagasta to Caldera.

NOTE: C. marginata, is the plant that was chosen as the type species of the genus when it was created by Britton & Rose. But for some 60 years, the true identity of C. marginata was the source of contention and discussions until Ritter designated the plants from Morro Copiapó as the neotype.

Conservation status: Listed in CITES appendix 2.
 

• Echinocactus marginatus Salm-Dyck
  Original Publication: Allgem. Gartenztg., 13:386 1845
• Echinocactus columnaris Pfeiffer 1847
• Echinocactus streptocaulon Hooker
  In: Curtis‘s Bot, Mag, 77 (1851)
• Echinocactus melanochus Cels
  in LAB. 1853
  Copiapoa streptocaulon (Hooker) Ritter
  In: K.u.a.S., H. 1, S. 4 1961
• Copiapoa bridgesii (Pfeifer) Backeberg sensu Ritter
• Copiapoa marginata var. bridgesii (Pfeiffer) Hoffmann
• Copiapoa chaniaralensis
  Distribution:,
• Copiapoa atacamensis
• Copiapoa lembckei Backeberg 1959
• Copiapoa calderana F. Ritter
• Copiapoa atacamensis
• Copiapoa calderana subsp. atacamensis.

Cultivation: Needs full sun, otherwise the bodies tended to elongate in cultivation, but it should be protected from excessive heat and sun in summer.  Requires light watering, and good drainage. Keep warm and dry in winter to avoid rot.  Frost tolerance 0°C

Propagation: Seeds (offsets rarely), Grafting is often used to speed growth rate, and to create a back-up to plants in collection.

Photo of conspecific taxa, varieties, forms and cultivars of Copiapoa calderana.
(This Taxon has lots of synonyms ( like many other Copiapoa) with several controversial varieties and subspecies, and comprises several different forms, but where each form is linked to others by populations of plants with intermediate characteristics):

• Copiapoa calderana
• Copiapoa lembckei (= C. calderana)
• Copiapoa magnifica (= C. lembckei var. magnifica)
• Copiapoa marginata (= C. calderana subsp. atacamensis)