A taxonomic review of five scorpaenid nominal species included in the Neomerinthe bucephalus species group [Neomerinthe amplisquamiceps (Fowler 1938), Neomerinthe bucephalus (Alcock 1896), Neomerinthe kaufmani (Herre 1952), Neomerinthe megalepis (Fowler 1938), and Neomerinthe procurva Chen 1981], characterized by a lateral lacrimal spine, recognized four to be valid (N. amplisquamiceps, N. bucephalus, N. kaufmani, and N. megalepis), with N. procurva regarded as a junior synonym of N. bucephalus. A lectotype was designated for N. bucephalus in this study. The valid species, supported by a molecular analysis based on the mitochondrial marker Cytochrome c Oxidase subunit I, can also be identified from combinations of the following characteristics: numbers of pectoral-fin rays, scale rows in the longitudinal series, scale rows below the lateral line, and scale rows between the sixth dorsal-fin spine and lateral line, eleventh dorsal-fin spine length, caudal-peduncle length and depth, and body coloration. In addition, the new species Neomerinthe harenartis is described based on four specimens collected from Vanuatu. This species, also bearing a lateral lacrimal spine, is distinguished from other Indo-Pacific Neomerinthe by having 19 pectoral-fin rays, 47 or 48 scale rows in the longitudinal series, 6 or 7 scale rows above the lateral line, and body depth 31.0–32.8% of SL, and lacking a second preopercular spine. A key to species in the N. bucephalus species group is given.