The area of West Africa covered by this book includes eighteen countries : Mauritania, Senegal, The Gambia, Guinea Bissau, Guinea, Sierra Leone, Liberia, Côte d'Ivoire, Mali, Burkina Faso, Ghana, Togo, Benin, Niger, Nigeria, Chad, Cameroon and Equatorial Guinea (Bioko). Chad, Cameroon and part of Equatorial Guinea (Bioko) are usually treated as part of Central Africa rather than West Africa but these countries have been included because their freshwater crab faunas are principally West African in character (although endemic taxa and other species of Central African origin may also be represented in these countries). The West African faunal region is an informal subdivision of the Afrotropical (Ethiopian) zoogeographical region, and lies to the south of the European and Middle Eastern components of the Palaearctic zoogeographical region, where freshwater crabs of the genus #Potomon$ (family #Potamidae$, Ortmann, 1896) are found. The West African freshwater crab fauna includes at least thrity-two species in seven genera and one family. This fauna is arguably the most diverse in Africa and has a distinct character which differs greatly from that found elsewhere on the continent. The present work brings together recent contributions to the taxonomy, distribution, and ecology of the entire West African freshwater crab fauna (Bott, 1955, 1959, 1964, 1969a, 1970a ; Monod, 1977, 1980 ; Cumberlidge, 1985a, 1987, 1991a, 1993a,b,c, 1994a,b, 1995a,b,c,d, 1996a,b, 1999 ; Cumberlidge and Clark, 1992 ; Cumberlidge and Sachs, 1989a, 1991) and presents new information on phylogeny and biogeography. The past ten years or so have seen the establishment of two new genera (#Potamonemus$ Cumberlide and Clark, 1992 and #Louisea$ Cumberlidge, 1994) and the description of a number of new species from West Africa... (D'après résumé d'auteur)