These works helped to expand the understanding of "Mammillaria" taxa. It is also known by many to be synonymous with "Mammillaria crinita" subspecies "crinita". The term "pincushion cactus" may also refer to the related "Mammillaria". The genus "Mammillaria" also contains "pincushion" and other cacti. The cacti of this genus bear many similarities to "Coryphantha" and "Mammillaria". "Mammillaria" is now recognized as the accepted spelling. Species similar to "Mammillaria spinosissima" include "Mammillaria backebergiana" and "Mammillaria meyranii". "Mammillaria bocasana" is hemispherical in shape. "Mammillaria hahniana" is one of several "Mammillaria" species to be cultivated. "Mammillaria carmenae" is one of several "Mammillaria" species to be cultivated. "Mammillaria bocasana" can be propagated from seed. Mammillaria rekoi is a species of cactus from Mexico. Specifically, "Mammillaria fraileana" has its own traits. Mammillaria senilis is a species of cacti in the subtribe Cactinae. "Mammillaria fraileana" commonly bloom from May to September.