Introduction
Sometimes plant names can tell you about the plants: the name Coryphantha was derived from two Greek words: koryphe (= head) and anthos (= flower). Thus, the flowers of Coryphantha arise from the top of the stem and not from side areoles.
The Details
Initially, Coryphantha was considered a Mammillaria-like group of plants, perhaps a subgenus of Mammillaria. Later Coryphantha came to be recognized as its own genus. Some would combine Escobaria into Coryphantha, but that discussion is not settled.
C. octacantha has 7 or 8 radial spines and 1 or 2(3) centrals. The name refers to the eight radial spines (oct = 8; acanth = spine).
The tubercles can be over an inch long and often have white wool at their bases. Old plants can be up to a foot tall or taller. The yellow flowers are about two inches across. The barrels are often solitary, but three or four stems may arise from the base. C. octacantha is a Mexican species mostly from Querétaro and Hidalgo states.
Additional Reading: Coryphantha sneedii Complex
