Opuntia mesacantha var. var. microsperma (Engelmann) J.M. Coulter

Opuntia mesacantha var. var. microsperma (Engelmann) J.M. Coulter is a synonym sensu Majure et al., 2017 of:

Opuntia cespitosa Rafinesque, an accepted species name sensu Majure et al., 2017.