Ferocactus are fierce cacti from Mexico and Southern USA. Leuchtenbergia consists of a single species, from Mexico.
Echinopsis now includes Lobivia, Tricocereus, Helianthrocereus, and Pseudolobivia.
An easy to grow cactus from Argentina, Southeastern Bolivia, Western Paraguay, Uruguay, and the Southernmost part of Brazil.
Three cactus genera from the Southern USA and Northern Mexico.
Small to medium cacti from USA and Mexico, often with brilliant flowers.
Eriosyce from Chile and Peru.
Mammillaria is one of the larger genera in the Cactus family, and one of the most variable.
The three most common types of mutation are crests, monstrose growth and variegation. All of these are mutations of the cellular structure.