[3] Cyphononyx fulvognathus is a solitary wasp that can be found in south-east Asia, notably between Japan, Taiwan and the south of China.

In Japan, it is the only species from the genus Cyphononyx.

The documented distribution of C. fulvognathus ranges from Japan, through Taiwan to south China.

In C. fulvognathus the vertex is more strongly raised between eye tops.

[2] Both males and females of this species typically have wings that are a yellowish-brown color.