Taxonomy of the West Indian cycads

Ten genera of Cycadalcs exist in world floras.Four genera, all members of the Zamiaceac, are natives of the Western Hemisphere, and two of these are found in the West Indian region.The monotypic Mkrocycas (Miq.) A. DC. is endemic to Cuba, while Zamia L. is found from Mexico south to Bolivia and Brazil, as well as in the West Indies (Schuster, 1932).Within the West Indian region, cycads are indigenous to all of the Greater Antilles, the Bahamas, Florida, and the southeastern coast of Georgia but are absent from the Lesser Antilles and the Virgin Islands.Because of its restricted distribution and seeming morphological isolation, Mkrocycas has heretofore caused little dispute, but the taxonomic history of West Indian zamias, like that of many other West Indian plant groups (Howard, 1977), has comprised a confusing array of divergent circumscriptions and delimitations, resulting in widely different species tallies (from one (present study) to 14 or more (de Candolle.1868)) for the region.Altogether, some 35 entities have been described, accounting for about 40 percent of the names proposed in the genus.Diverse taxonomic treatments can be ascribed to complex variation patterns and political fractionation of the region, as well as to differences in philosophy among taxonomists.Most previous workers have had a very narrow species concept and have acknowledged neither extensive variation within populations nor continuity between populations.Often species were described on the basis of single specimens â€" sometimes cultivated plants for which the original sources were unknown.Other than Schuster's (1932) synonymies, which are tortuous and partly invalid under the present International Code of Botanical Nomenclature, there has been little effort to consolidate nomenclature in different subregions, and nomenclature] and taxonomic chaos persist.This paper proposes a new taxonomy of West Indian cycads, based on field, herbarium, and garden studies; explains the contrast between this classification and those of previous workers; and accounts for most published names in the complex.