The geographic area covered by this catalog is the Neotropical Region including Mexico, Marginal areas such as the Bahamas Islands, Islas Malvinas, the Juan Fernandez archipelago and Easter Island are also covered. This catalog lists 959 species distributed into 158 genera and presents a complete list of the species that have been reported from this region until August 1, 1989. All reference that deal with the biology or taxonomy of the Neotropical Collembola are included, as well as the fauna of Nearctic areas of Mexico. The catalog incorporates the latest advances in collembolan taxonomy, maintaining a balance between the most conservative and liberal classifications. Under each family or subfamily, the catalog groups genera which are closely related. Under each genus or subgenus it lists the species in alphabetical order.