Phymatopus (originally: Noctua Linnaeus, 1758) is a genus of moths of the family Hepialidae (commonly referred to as swift moths or ghost moths), which consists of around 500 species and 30 genera. The genus was erected by Hans Daniel Johan Wallengren in 1869. They can be found across Eurasia and North America. Species can be distinguished by the different morphology of male genitalia and different forewing patterns, which vary in stripe colour and size and arrangement of spots. The stripes themselves consist of spots separated by dark veins which are fringed by thin black lines from both inner and outer sides.