Twelve new species of Eustomias (Dinematochirus) are described from the Indo-Pacific, and new specimens of Eustomias similis, a species previously known from only the holotype, are reported. All have two pectoral fin rays and relatively short barbels with pigmented stems; all but one have a branch or branches off the barbel stem. In addition, several Indo-Pacific specimens with two pectoral fin rays and very rudimentary branches off the barbel stem are informally described as forms of uncertain status. One of the new species occurs throughout the Indo-Pacific and in the southeastern Atlantic. Three others occur in both the north and south Pacific and another in equatorial waters of the western Pacific and Indian Oceans. The remainder appear to have relatively restricted ranges in the Pacific. With these new species, the genus Eustomias now includes 113 species, and the subgenus Dinematochirus 40 species plus several forms of uncertain status. Within Dinematochirus, 14 species are known only from the Atlantic, 19 only from the Indo-Pacific, and seven from both. A key to the species or species groups of the subgenus is provided.