The major emphasis of this chapter is to address the species richness and population densities of land vertebrates in riparian mesquite bosques (woodlands). We find no single publication that lists vertebrates - amphibians, reptiles, birds, and mammals - of riparian mesquites of the Southwest lowlands. These vertebrates are listed for a few river valleys, such as the Santa Cruz River (Webb et al. 2014) and San Pedro River (Stromberg and Tellman 2009), but not for the Southwest as a whole. This chapter presents a summary of the vertebrate fauna of mesquite bosques. Our lists of vertebrates of bosques and/or associated cottonwood-willow forests and riparian deciduous woodlands have been constructed from literature, historic records and specimens, and our first-hand knowledge.