ABSTRACT
From the Greek dis ‘twice’ and oon ‘egg’, orth. var., see Edwards’s Botanical Register 29: misc. 59–60. 1843 and Paolo Caputo, Dennis W. Stevenson and Eleanor T. Wurtzel, ‘A phylogenetic analysis of American Zamiaceae (Cycadales) using chloroplast DNA restriction fragment length polymorphisms.’ Brittonia 43(3): 135–145. July–September 1991, Govaerts, R. World Checklist of Seed Plants Database in ACCESS D. 2000 [as Dioon.], Maarten J.M. Christenhusz et al., ‘A new classification and linear sequence of extant gymnosperms.’ Phytotaxa 19: 55–70. 2011.
