The following list of non-marine gastropod fauna summarizes the known species and subspecies that are recognized from Mexico and Central America. It is an annotated list of 1789 terminal taxa presented in a hierarchical framework. These include 1491 native species plus 278 native subspecies, and 20 introduced species. The native species include 168 aquatic operculates, 84 aquatic pulmonates, 130 terrestrial operculates and 1109 terrestrial pulmonates. In most cases in order to be as objective as possible the list uncritically records the most recent assignment of terminal taxa. In a few instances some changes are deemed necessary. For higher-level changes competing schemes are treated equally. In cases of terminals and higher taxa readers are directed to the systematic works that discuss relevant taxonomy. It is anticipated that the annotated list will be a useful resource for everyone interested in non-marine gastropods and their nomenclature. In addition to clarifying some issues or points of confusion, this list should also provide an impetus for future work aimed at clarifying and resolving areas of taxonomic disagreement and/or uncertainty, and to make better known the non-marine molluscan fauna of Mexico and Central America.


The objective of this study is to list all species and subspecies of land and freshwater gastropods reported from Mexico and Central America. The list includes 1491 native species plus an additional 238 native subspecies, and 20 introduced species. The list includes published distribution records within this area for all terminal taxa. In only a few instances are unpublished distribution records included. The following geographic terms are used. North America refers to the North American Continent, which extends south to the Polochic Valley in Guatemala. Central America refers to the countries of Panama, Costa Rica, Nicaragua, Honduras, El Salvador, Guatemala, and Belize, including Caribbean and Pacific Islands belonging to these countries. Middle America refers to Central America and the West Indies.

The geographic area of this study is vast, and it contains many biomes, different geological structures, complex physiographic features and a myriad of ecological settings. Local surveys have been published for only a small portion of this area. It is not possible on the basis of published information to identify biotic hotspots, because the available biogeographic information does not allow for objective comparisons of one region with another. A disproportionate large number of species have been recorded from central Veracruz, Mexico, but this is a reflection of the number of investigators who have worked there. Even these investigations were localized within smaller sub-regions of central Veracruz. The localized regional data are not comparable because of historical sociopolitical circumstances effecting access, available transportation, duration of field work, and the emphasis different investigators placed on certain taxa. The extensive limestone terrains of southern and western Mexico promise to be as species diverse as central Veracruz, but their faunas are greatly under-reported.

The number of known taxa from Mexico-Central America is large. Nearly all of the know species are based on sound taxonomic studies and reviews dating back to Shuttleworth, Menke, and Pfeiffer.  I estimate that the number of recorded taxa is about 35% of the actual fauna. The high number of estimated undescribed species is based on the fact that most of Panama, much of Costa Rica, most of Nicaragua, nearly all of Honduras, most of Guatemala, nearly all of Belize, and 85% of Mexico have not been explored, or have been poorly explored for mollusks, especially small and minute species.  I have collected extensively in these areas, and my field work yields results comparable with the reported faunas of better known regions.  I estimate that the number of recorded taxa is about 35% of the actual fauna. This estimate is based on fifty-five years of personal field experience in this area, and upon the extensive specimens deposited in the Florida Museum of Natural History. Each new field trip yields spectacular finds of which up to 40-80% are additional new species.  I suspect the estimate that only 35% of the actual Mexican-Central American fauna is known is conservative.

The purpose in publishing this as an on-line publication is to make the checklist immediately available and free to anyone who is interested.  To publish it as hard-copy would be costly and beyond the affordability of very many potential users.  The checklist is intended to be a summary of the literature.  The user can proceed from there.   It is not intended to be an identification manual.  Therefore no illustrations are included, because it would take several more years to correctly identify most of the needed species.  These can be added later at very little cost.

Systematic biology is made unnecessarily difficult by the tendency of authors to synonymize species or to resurrect them from synonymy without providing justification. In either case the responsibility is on authors to provide evidence supporting their actions. To do otherwise is poor science. Merely to state that a name is a synonym does not constitute a valid action.

In accordance with ICZN Article 45.6.4, and for purposes of this work, varieties and forms of species published prior to 1961 are accorded subspecific rank. No judgment is made concerning the validity of such subspecies.