Most other species lack the dentate forewing termen. Very similiar to A. sericeus however the ground colour in that species is a much deeper violaceous-grey and more variegated in brown. The inner arm of the discal FW λ pattern of A. sericeus is much more distinct.
 Very similar and easily confused with Acosmeryx sericeus. Upperside of body and wings more uniform in colour, much less variegated in with grey and chestnut than in Acosmeryx sericeus. Thorax underside more olivaceous than in Acosmeryx sericeus. Abdomen underside less bright tawny than in Acosmeryx sericeus. Forewing upperside with brown, curved, antemedial band less extended than in Acosmeryx sericeus, the two lines that form it being separate for the greater part; first discal line narrow, broken at the veins, as are the subsequent lines; the bars between veins CuA1 and CuA2 of lines 3 and 4 heavier and closer together, often forming a single patch; an oblique band present, positioned as in Acosmeryx sericeus, narrower anteriorly, somewhat dilated distad at vein M2. Both wings undersides with costal margins less marked than in Acosmeryx sericeus, and the tawny colour more restricted and less bright. Hindwing upperside with dark discal and submarginal bands present, as in Acosmeryx sericeus. Hindwing underside with a distinct white line at the distal border with, as in Acosmeryx sericeus, widest between veins M2 and M3, not just at M2 (Sphingidae Taxonomic Inventory, 2021).

Similar species: ​​​​​​​Acosmeryx castanea Rothschild & Jordan, 1903
Wings less elongate than in Acosmeryx omissa, not dentate, or at most with vestigial teeth. Forewing upperside similar to that of Acosmeryx omissa; antemedian band more or less completely brown; oblique discal band with proximal edge more curved than in Acosmeryx omissa, extending distad between veins M2 and Cu1; first discal line almost as indistinct as in Acosmeryx omissa against the dark background, the bars between veins Cu1 and Cu2 of lines 3 and 4 not heavier than the others, nor closer together; subapical grey area sharply delimited at vein M2, as in Acosmeryx naga naga, not extending beyond this vein. Outer discal area of forewing and discal area of hindwing undersides a more reddish tawny than in Acosmeryx sericeus, and considerably more so than in Acosmeryx omissa. Forewing underside with grey costal scaling no more conspicuous than in Acosmeryx omissa; grey scaling within the distal marginal border diffuse, less distinct than in Acosmeryx omissa. Hindwing upperside less olive-grey than in either Acosmeryx omissa or Acosmeryx naga; discal area somewhat cinnamon-rufous along the distinctly marked, chestnut-olive, distal marginal band; a faint discal line present running from the costa to the hind angle. Body upperside chestnut brown, shaded with grey; dark markings of thorax and abdomen indistinct. Thorax underside olivaceous cinnamon-rufus. Abdomen underside ferruginous. (https://tpittaway.tripod.com/china/a_cas.htm).