The differences between the subspecies are:
-ssp. polythele: The stems are 3-4 inches thick. It has 2 spines per areole on the new...Read More growth and later developes 3-4 spines per areole.
-ssp. durispina: The stems are 2-2.4 inches thick. The spines number from 6-8 per areole at different lengths.
-ssp. obconella: The stems get up to 6 inches thick. It has four spines per areole arranged like a cross.
The cultivar 'Toluca' has no spines or one or two small spines per areole and the flowers are deep red as opposed to magenta like the other subspecies of Mammillaria poythele are.
The 'nudum' form has no spines at all.
More synonyms of this plant are: Mammillaria rigidispina, Mammillaria affinis, Mammillaria neophaeacantha, Mammillaria subdurispina, Mammillaria xochipilli, Mammillaria multimamma, Mammillaria kelleriana, Mammillaria quadrispina, Mammillaria polythele var. hexacantha, Mammillaria polythele var. quadrispina, Cactus polythele, Cactus quadrispinus, Cactus tetracanthus, Cactus polythele, Neomammillaria tetracantha, Neomammillaria polythele, Neomammillaria hoffmanniana, Neomammillaria kewensis
The differences between the subspecies are:
-ssp. polythele: The stems are 3-4 inches thick. It has 2 spines per areole on the new...Read More
Solitary larger Mammillaria from Mexico.. only seen one example and it certainly wasn't solitary... hmmm.