Last Friday four professors from Cuernavaca
arrived with botany students and I became their botanical guide until Sunday afternoon.
For me the star destination was 8500- ft-high (2600 m) Cuatro Palos (meaning "Four
Trees"). Up there the light is crystalline and sharp, the view majestic, and plants
and animals are especially adapted for edge-of-world conditions. One view can be seen at
At a rocky, exposed tip of a limestone ridge above the village several fabulous plants
found a foothold. One little gem was a small, oval, sublimely spiny and flowering cactus,
The locals gave the name of this cactus as Biznaga. But I've heard that name many times
before. In fact, Mexicans call any roundish, very spiny cactus Biznaga. An unflowering
Mammilaria growing nearby with a completely different body structure (composed of
"nipples" instead of "ribs" like our flowering one) also was called
Biznaga. We were told about waist-high, barrel-shaped cacti with foot-long spines living
down lower in the dry valley and they also were Biznagas. There couldn't have been a
better demonstration to the students of the value of scientific names, for if you're
trying to determine whether a species is rare or not, how can you even talk about it if
everything is called "Biznaga"?
We set ourselves down next to the "Biznaga" and began "keying it
out," using a technical dichotomous key. Right off, the key asked whether glochids
were present. Remember that glochids are tiny spines at the base of big spines. Our
specimen had no glochids. Other important features of this species were that its body
surface was folded into thin, waferlike, vertical, sinuous ribs atop which the spines
arose, and the flowers sprouted from the cactus's top-center, not from along its sides.
Our cactus turned out to be a member of the genus Stenocactus, which is endemic to
Mexico. It was STENOCACTUS CRISPATUS. Apparently the species has no common name because
it's not commonly known, but plant taxonomists sure have kicked it around, giving it one
scientific name after another. I count about thirty scientific names it's been known as.