The Aleiodes bakeri (Brues) species subgroup of the A. seriatus species group is defined based on two previously described species, A. bakeri and A. nigristemmaticum (Enderlein), and is greatly expanded in this paper with an identification key, descriptions, and illustrations of 18 new species from the Neotropical Region: A. andinus Shaw & Shimbori, sp. nov.; angustus Shimbori & Shaw, sp. nov.; asenjoi Shimbori & Shaw, sp. nov.; bahiensis Shimbori & Shaw, sp. nov.; barrosi Shimbori & Shaw, sp. nov.; brevicarina Shimbori & Shaw, sp. nov.; coariensis Shimbori & Shaw, sp. nov.; goiasensis Shimbori & Shaw, sp. nov.; gonodontivorus Shaw & Shimbori, sp. nov.; hyalinus Shimbori & Shaw, sp. nov.; inga Shimbori & Shaw, sp. nov.; joaquimi Shimbori & Shaw, sp. nov.; lidiae Shimbori & Shaw, sp. nov.; mabelae Shimbori & Shaw, sp. nov.; maculosus Shimbori & Shaw, sp. nov.; ovatus Shimbori & Shaw, sp. nov.; santarosensis Shaw & Shimbori, sp. nov.; and taurus Shimbori & Penteado-Dias, sp. nov. It is hypothesized that the A. bakeri species subgroup is a monophyletic lineage within the larger and probably artificial A. seriatus species group (those Aleiodes with a comb of flat setae at the apex of the hind tibia), and can be distinguished from other members of the seriatus group by having the hind wing vein r present, although weakly indicated; the hind wing marginal cell suddenly widened at junction of veins RS and r; the subbasal cell of the fore wing mostly glabrous but often with two rows of short setae subapically; glabrous regions of the wings also commonly found in the first subdiscal, discal, and basal cells of the fore wing, and the basal cell of hind wing; ocelli quite large, with the width of a lateral ocellus being distinctly larger than the ocellar-ocular distance; and being relatively large Aleiodes species with body almost entirely brownish yellow or reddish brown. In addition, a new replacement name, Aleiodes buntikae Shimbori & Shaw, nom. nov., is proposed for the species formerly called Aleiodes (Hemigyroneuron) bakeri Butcher & Quicke, 2011.