Termites are a diverse and important group of insects in the New World, the Neotropics being the second zoogeographical region in number of species. The rain forests and savannas of South America bear particularly rich and abundant termite faunas, rivaled only by the forests and savannas of Africa.

Hagen (1858), in his monograph on termites, listed 41 species from the Americas, 36 of which are still recognized as valid. It is interesting that, at that time, the New World fauna comprised 42% of all known termite species, about twice the current proportion. Forty-six years later, Desneux (1904b) presented a world catalog, listing 86 New World species (77 still recognized). Following a period of intense taxonomic work by several authors, the number of living New World genera and species reached 55 and 395, respectively, in Snyder's (1949) catalog, of which 385 species are still valid. The rate of discovery of new taxa gradually declined, in part because the number of active taxonomists decreased. Araujo (1977) presented the first catalog of termites of the New World, in which he listed 70 genera and 471 species (excluding fossils). New taxa continue to be discovered in this region, mainly from tropical South America, and most genera need taxonomic revision. This is particularly necessary for Nasutitermes and Anoplotermes, and will probably result in many new species and also new synonymies.

 Since the publication of Araujo's catalog, 16 new genera have been described, one subgenus has received the status of genus, and one genus has been placed in synonymy, resulting in a total of 86 genera for the New World. Seventy new species have been described, six species are now regarded as synonyms, three junior synonyms have been revalidated, two subspecies have been elevated to species status, two species not included by Araujo (Cryptotermes darwini and C. venezolanus) have been added, one more introduced species has been recorded (Reticulitermes lucifugus), resulting in a total of 543 species (excluding names of uncertain position).

 The exact number of Neotropical and Nearctic species depends on how the limits between these two regions are defined. Also, some species are known only from the overlap zone between the two regions and it is difficult to determine whether they are Neotropical species which reach their northern limits in this zone or the reverse. The figures below assume the limit to be the Tropic of Cancer except for the highlands of Mexico, whose fauna is considered Nearctic. All Nasutitermes species are treated as Neotropical and all Gnathamitermes as Nearctic. The total number of species recorded for the Nearctic region is 48, of which three are introduced house pests. The number of species for the Neotropical region is 505 (six introduced). Nine native species occur in both regions: Cryptotermes cavifrons, Incisitermes marginipennis, I. milleri, I. schwarzi, I. snyderi, Neotermes castaneus, N. jouteli, Prorhinotermes simplex, and Anoplotermes fumosus. However, some of these are restricted to southern coastal Florida within the Nearctic region and might be considered Neotropical only.

 The catalog presented here is based on an extensive review of the literature, and is not a simple update to Araujo's catalog. Besides adding new taxa and nomenclatural changes, several errors found in the previous catalogs are corrected. Unlike Snyder's and Araujo's catalogs, only living species are included. Several names are placed in uncertain position at the end of the catalog. These are available names associated with very poor descriptions which, at present, cannot be classified. Most of them are probably synonyms, but some might become senior synonyms. However, I have not seen types of any of them and they should be reexamined, if they can be located.

 The catalog is in alphabetical order, organized by families, subfamilies, and genera. An index to species, including synonyms, is included. If necessary, search functions of the web browser can be used to locate names. The information on geographical distribution is based mostly on the literature and should not be considered very accurate. The distribution of most species is still poorly known and will certainly be expanded with new surveys and study of collections. If no information on distribution is included, then the species is known only from the type-locality or the vicinities.

 I did not try to provide a complete list of references for each taxon, but tried to cover all taxonomic literature, listing all known synonyms. I have also included a selected bibliography with information on geographical distribution, morphology, and biology of New World termites. A complete bibliography can be found in Snyder (1956b, 1961, 1968), Ernst & Araujo (1986) and Termite Abstracts. The list of misspellings is not complete, but includes the errors found in Snyder's (1949) and Araujo's (1977) catalogs. Most subgenera were raised to genera in Snyder's (1949) catalog. In order to save space, these changes are not indicated individually for each genus or species. Unless otherwise stated, type-species were designated in the original description of genus.

 The list of synonyms is organized in the following order: the original publication, objective synonyms in chronological order, subjective synonyms in alphabetical order, misidentifications in alphabetical order. For each different name, additional references are listed in the same line, in chronological order. Note that a misidentification may be an objective synonym if the same specimens become types of a new species.

 Snyder (1949) and Araujo (1977) included some manuscript names in their catalogs. Those are nomina nuda (singular nomen nudum), have no standing in Zoological Nomenclature and should never be recorded, even in synonymy. This question is related to the concept of availability as defined by the International Code of Zoological Nomenclature. This catalog does not include any nomen nudum. One example of a publication with several nomina nuda is Mathews (1977), in which many new species are described with two different names, one in the text and another in the figure captions. According to the Code, names associated only with illustrations published after 1930 are not available and, therefore, they are nomina nuda and cannot be considered synonyms.