Cochemiea

Cochemiea is a genus of cactus. The group was previously synonymized with Mammillaria, until molecular phylogenetic studies determined that—when broadly circumscribed—Mammillaria is not monophyletic; thus, Cochemiea has been accepted as a distinct genus.

The Cactaceae family, as a whole, is the fifth most-endangered plant or animal family taxon, globally, as evaluated by the International Union for the Conservation of Nature (IUCN). The reasons for this are varied, ranging from climate change and habitat loss, in some regions, to the illegal harvesting (poaching) of wild cacti for personal collections or sale on the black market, or blatantly sold, as-is, fresh from the wild. As these plants are naturally slow growers, wild cactus growth and reproduction rates may not meet the rate at which certain populations of species are being poached, thus creating gaps in the wild populations and risking complete regional depletion or extinction.

Taxonomy
A 2021 molecular phylogenetic study of the "mammilloid clade", which included the genera Cochemiea, Coryphantha, Cumarinia, Escobaria, Mammillaria, Neolloydia and Ortegocactus, showed that it consisted of four monophyletic groups, which the authors re-circumscribed into four genera: Cumarinia; Mammillaria, with a reduced number of species; Coryphantha, expanded to include species previously placed in Mammillaria and Escobaria; and Cochemiea, expanded to include a large number of species previously placed in Mammillaria, as well as Neolloydia conoidea.

Species
In 2021, Breslin, Wojciechowski and Majure placed the following species in the genus, some already placed there and some moved from Mammillaria, Neolloydia, Neomammillaria and Ortegocactus. , Plants of the World Online accepted in the genus the species moved by Breslin et al.