Ptyxis in Ceratozamia A–C Ceratozamia miqueliana D–F C. matudae.
Part of:
Martínez-Domínguez L, Nicolalde-Morejón F, Vergara-Silva F, Stevenson DW (2022) Monograph of
Ceratozamia
(Zamiaceae, Cycadales): an endangered genus. PhytoKeys 208: 1-102.
https://doi.org/10.3897/phytokeys.208.80382