The stripes themselves consist of spots separated by dark veins which are fringed by thin black lines from both inner and outer sides.

nec Wallengren, 1869 The genus Phymatopus is considered monotypic and species can be distinguished by forewing pattern and male genitalia.

The male forewings bear two silvery white stripes consisting of individual spots separated by dark veins, which are fringed with thin black lines.

[3] Phymatopus hecta japonicus is found located in the Russian Far East: Sakhalin island and southern Kurils; south of the Daisetsu mountains, Hokkaido, Japan.

The morphology of the male genitalia is also different from that of P. hectus, the ventral process of valvella is belt like, which tapers to a point as it reaches the distal quarter, the dorsal margin of valva is convex.

In male genitalia, the dorsal process of valvella is strongly curved in the distal part, giving it a hook-like appearance; there is also a clear cavity at the tip of the mesosome.

The Eurasian range consists solely of Phymatopus hectus, and in North America the genus is represented by three species, which are geographically restricted to the western coastal region of the United States.

According to van der Meulen and Groenendijk's classification, Phymatopus exhibit area restricted, limited wandering behaviour and small flight range.