Critical review of “Monograph of Ceratozamia (Zamiaceae, Cycadales): an endangered genus” published in PhytoKeys 208: 1–102 (2022)

Abstract

The recent publication of a monograph on Ceratozamia promised greater taxonomic understanding in the genus. Instead, the plethora of inaccuracies and inconsistencies therein undermined taxonomic cohesiveness. This review critically evaluates the Ceratozamia monograph of Martínez-Domínguez et al. (2022), systematically correcting the inaccuracies and clarifying the inconsistencies therein. Notably, the proposed lectotypification of C. mirandae is invalidated, the proposed specific status of C. osbornei is questioned, the proposed synonymy of C. dominguezii under C. subroseophylla is rejected, the proposed recircumscriptions of C. sancheziae and C. zoquorum are refuted, and a lectotype and isolectotype for C. whitelockiana are designated. Additionally, evidence is provided for phenotypic and ontogenetic plasticity of cone color, ovulate cone apex shape, megasporophyll horn shape and orientation, megasporophyll distal face prominence, and microsporophyll distal face topology. Finally, within Ceratozamia, ‘mucronate’ is standardized over ‘apiculate’, ‘conspicuous’ is standardized for leaflet vein light transmission, and ‘prominent’ is standardized for vein protrusion from the leaflet surface; in addition, ‘vernation’ is standardized over ‘ptyxis’ across the Cycadales.