Peristiwady T (2011) Their body proportions were nearly the same. However the later species had longer body width, third dorsal and second anal spine but had shorter longest dorsal ray length, longest anal rays, caudal-fin length and caudal concavity. Other little different characters of O. unimaculatus with other seven species were the proportion of upper jaws length and proportion of body depth. Initially this species was described as new species from Tanabe, Wakayama Prefecture, Japan. Other specimens were reported from Suruga Bay, Japan, Keelung and Kaohsiun, Taiwan and Lubang Island, Philippines and now recorded also in Bitung, North Sulawesi, Indonesia.