araneispinus (also considered just a form of D. zehntneri) is
a squat tiny little solitary plant that - in culture - produces just
like D. boomianus many offsets.
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-withe to light-brown with yellow to brownish bristles up
to 2 cm..
Ribs: About 20, somewhat spiraled, 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: White, scented, slender funnelform, up to 9 cm long. The
position of the stigma is at the top of the stamens. Each flowering
lasts only one night, but that night it produces many flowers.
Fruits: Club-shaped red 2,5 cm long. The plant produces seed-pods
twice a year, when it flowers.
This plant is part of the D. zehentneri
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: Sentocé)
subsp. horstiorum Slow growing form = D.
zehntneri (Origin: near Minas do
Mimosa, Moreno, Sierra do Espinahaco, Bahia )
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.