The Madras Goatfish, Upeneus madras n. sp. (Mullidae), is described based on two specimens from Chennai, SE India, that were formerly identified as U. guttatus (Day, 1868), a widely distributed species which has the same type locality. The new species shares white barbels and oblique bars on the lower caudal-fin lobe, seven dorsal-fin spines which decrease proportionally in height and subequal pelvic and pectoral fins with the other eight species of the pori group, a newly established taxonomic species group. Upeneus madras n. sp. differs from all eight species in the lack of bars along the dorsal margin of the lower caudal-fin lobe and from the four most similar species mainly in the combination of caudal-peduncle shape and pectoral-fin width. Detailed comparisons with U. guttatus, a japonicus-group species, were made involving the study of two syntypes collected by Francis Day (the taxonomic authority of U. guttatus), from which we designate a lectotype. This species differs from U. madras n. sp. in yellow vs white barbels, shorter head, narrower pectoral fins and a mostly higher first dorsal fin with disproportionally elongated anterior spines. A review of barbel colour in the 47 Upeneus species suggests high diagnostic significance of this character for the distinction of several species and taxonomic species groups.