ABSTRACT The erethizontid rodent genus Coendou (including Echinoprocta and Sphiggurus) contains 13 valid species that live in tropical and subtropical forests from Mexico to Uruguay. This report tabulates information about the type material of all Recent nominal taxa referred to the genus, provides synonymies of all species recognized as valid, describes geographic distributions based on examined specimens, cites published descriptions of external and craniodental morphology, summarizes information that supports recommended binomial usage, and suggests where future taxonomic research is likely to be productive. Among other novel results, the nominal taxa richardsoni J.A. Allen, 1913, and rothschildi Thomas, 1902, are synonymized with C. quichua Thomas, 1899; a Paraguayan neotype is designated for C. spinosus (E Cuvier, 1823); and a specimen of C. rufescens is reported from Bolivia, extending the range of that species by 1800 km. Additionally, morphometric data are tabulated for several species not treated...