In Japan they are called Imori. To distinguish between species in the three groups is fairly simple by carefully observing color patterns, skin texture, and other secondary characteristics. Cynops are divided into groups based on their geographical and physical characteristics. According to studies, the Japanese phyrrhogaster group is the most primitive of the three. These are some of the characteristics used by scientists to determine which genus an animal belongs to, so it is possible that these species in the genus Cynops may be elevated to genus or subgenus level.
Much research needs to be done.
It is also noted that newts in the phyrrhogaster group have the largest geographic distribution among the Cynops newts. The oldest groups will tend to have the widest distribution and, because of the frequency of extinction, will also exhibit the most discontinuous ranges. The Atlas of Reptiles and Amphibians for the Terrarium, published by T.F.H. and edited by F.J. Obst, et al, mentions that there are 8 forms, of which 5 have been elevated to species level. They are closely related to the European newt genus Triturus. Newts in the genus Cynops, except C. ensicauda, live in cool water, and all are aquatic most of their life.