Basic morphology, scanning electron microscopy, and DNA sequence data from the plastid trnL–F region and the nuclear internal transcribed spacer (ITS) regions were used to delimit the species of a recently circumscribed clade of Cuscuta (Convolvulaceae) and to investigate their phylogenetic relationships. This clade comprises the Cuscuta gracillima complex from Mexico, Central and northern South America, a group which is characterized by inflorescences that appear to emerge directly from the host stem. Eight lineages are recognized, with two of them described here as new species: Cuscuta punana Costea & Stefanović, sp. nov. from Ecuador and Cuscuta vandevenderi Costea & Stefanović, sp. nov. from Mexico. Cuscuta colombiana Yunck is redefined to include Cuscuta aristeguietae Yunck., and Cuscuta deltoidea Yunck. is broadened to encompass Cuscuta serruloba Yunck. A taxonomic treatment with an identification key, descriptions, and illustrations is provided; the biogeography and conservation status of the eight species are also discussed.