Atypical' species of Aulacaspis, scale insects referable to the genus but not conforming with the type species in body shape, are dealt with; 21 species including 17 new species are described, three undetermined and seven known species are briefly noted, and l0 published names are mentioned. Not all of them are closely related to each other, so that the atypical species do not form their own taxonomic group within the genus. The calcarata species group is composed of nine species similar to each other in certain pygidial characters; five of them are typical and the other four atypical in body shape, the latter exhibiting two types of body shapes. These species suggest the emergence of the different body shapes within the group. The antennae of the first instar are six-segmented in six species, whereas five-segmented in many others; the possibility that the number of the antennal segments sometimes changes between closely related species is not excluded.