Coryphantha scheeri var. robustispina
(Coryphantha robustispina)
Pima Pineapple Cactus

Federal Threatened and Endangered Species status:  ENDANGERED
THREATS:  Aggressive development.  Also grazing, off-road driving, and possibly collection.
Photos on this page were taken in an area where the cacti are especially abundant.  Since July 2000,
development has destroyed many plants in this locality and over one hundred square miles of habitat.
Identified by its very large tubercles, stout spines, yellow flowers, and geographic range:
Sonoran desert upland and grassland surrounding the Santa Rita Mountains, Pima and Santa Cruz Counties, Arizona.
NOTE:  This cactus appears on the USFWS Federal Endangered Species list as "Coryphantha scheeri var. robustispina".
In the Flora of North America it is C. robustispina.
Southern Arizona Desert Botany

Bloom Day - July 15, 2010 - Celebrating ten years in Pima Pineapple Cactus Land!  More photos on my BLOG.

MONSOON FIRE!  July 2003
Flower color varies from pale straw yellow to lemon or
deep gold.  Backs of petals are pinkish bronze.
POSTCARD at CafePress.
Flower buds develop in spring, but remain dormant
until several days after the first significant monsoon rain.
All plants bloom at once, and only for one day.
In wet years, plants may bloom twice (May and July).

A dead plant becomes a hollow ball of spines.
(The "monsoon fire" plant, July 2006.)
Why it's called PINEAPPLE cactus. Shallow radiating roots drink the sheetwash.
Unlike many other barrel-type cacti, there
is no central "umbilical cord" or taproot.

Flowers (like those of many cacti) are slightly fluorescent in daylight.  This adds a subtle glow to their earthy/sunny beauty,
but can be quite difficult to photograph, especially since "bloom day" is usually humid and partly cloudy.

As pretty as the flowers are, they are of only minor use in identifying the cactus.
The plant itself is distinctive and uniquely beautiful, and unlikely to be confused with any other cactus within its range.
This photo shows the characteristic large knoblike tubercles and stout, colorful spines.

All Coryphantha species have TUBERCLES with a central groove on top.
Vegetative buds have no central spine on the first row of tubercles.
New tubercles with soft spines crown the plant in spring.
FRUITS are greenish yellow.  Photo taken in mid-
August shows two ripe fruits from May flowers
and five smaller fruits from late July flowers.

Mature plants often produce vegetative "buds" at the base.  These are individual young plants that can survive if the old plant dies.
In a wet spring they may produce several tiny buds at once.  In rare cases, several "generations" of buds form a complete ring around the parent plant.
The bud-producing strategy may be an adaptation to temperature extremes (105+ summer highs and occasional winter freezes) in a very dry environment.
It is also seen (though less frequently) in the Arizona Turk's Head Cactus and Needlespine Cactus.  (Go to HOME for more photos of these species.)
The plant pictured below was found in July 2000 with 12 buds, each about one inch in diameter.  By 2006, the plant had 22 buds in three size classes.

2001 2002 2003 2006

July 14, 2004 July 2, 2006

July 25, 2007

PAINTING:  Handground mineral pigments in egg tempera.  Copyright 2000 by Lorena B. Moore.

Young Arizona Barrel Cactus  Ferocactus wislizeni
Compass Barrel, Fish Hook Barrel.  MORE PHOTOS
The unique Pima Pineapple Cactus often grows with the barrel cactus (young plant shown above).
Barrels have longitudinal RIBS, not conical TUBERCLES.  Large red central spines are flattened, ridged, and always hooked.