Description: Discocactus buenekeri (also considered just a form of
D. zehntneri) is a
globose-flattened tiny little plant that (in
culture) grows in small groups just like D. boomianus..
Stem: Dull-green 10-20 in diameter and 7-10 cm tall.
Cephalium: Up to 1 cm tall and -4 cm wide, at the apex of the
plant, creamy-white to light-brown with yellow to brownish bristles up
to 2 cm. The size of the cephalium on this specimen is often as
large as the cactus body!
Ribs: About 20, somewhat spiralled, forming nipple-like tubercles
to 1 cm high.
Areoles: Oval, sunken, ca. 8 per ribs.
Radial spines: Interlacing, densely covering the plant, 10 to15
up to 1-2 cm long, pectinate, flexible spines creamy white or
whitish-yellow with dark tips, becoming pale-brown to whitish, recurved
backwards, sitting on the plant like spiders.
Central spines: None.
Flowers: Cream-white, with
heavenly scent, slender funnelform, up to 9 cm long. The position of the
stigma is at the top of the stamens. The bud appears, grows and
opens all within 24 hrs. Each flowering lasts only one night, but that
night it produces many flowers.
Blooming season: This species usually blooms in April, May, or
June or as late as August.
Fruit: Club-shaped, white.
Remarks: This plant is part of the D. zehentnari complex which comprises several variable subordinates taxa,
but not all are universally recognized. Some
authorities recognize only the following :
subspecies, varieties and forms:
subsp. zehntneri Usually globose and
completely covered in white thin, needle-like spines, the flower is
about 3 cm long and the fruit are red (Origin: Sentocť)
subsp. horstiorum = subp zehntneri (Origin: near
Minas do Mimosa, Moreno, Sierra do Espinahaco,
subsp. boomianus Usually disk -shaped, with dark tipped
yellowish spines, the flowers are up to 9 cm long (Origin: Sierra do
subsp. buenekeri this species does share the complex
commonality of tuberculate ribs and basal offsetting, but its white,
club-shaped fruit does not fit with the dark red , much elongated and
slender fruit of the other taxa.
subsp. araneispina has flexible,
interlacing spider-like spines that cover the plant.