Trichoptilus viduus is a moth of the family Pterophoridae that is known from South Africa.

The abdomen is ochreous-grey, with a lateral row of white spots.

There are narrow irregular white transverse bars on both segments.

The cilia are grey mixed with blackish towards the base and with white spots on the margins of the markings and above and below the apex of each segment, on the dorsum with blackish scale-projections between these.

The cilia are fuscous, on dorsum with a rather small blackish scale-projection and a few white scales before this.