Bathynotus is a genus of trilobites of the family Bathynotidae.

Its fossils have been found in the paleocontinents Laurentia (specifically in what are now Nevada and Vermont), Gondwana (in South China and South-Australia), and - doubtfully - Siberia.

It is characterized by a very wide axis in the thorax and an enlarged 11th segment that bears a long, backwardly directed spine on each side.

[2] Bathynotus is derived from the Greek words βαθυς -bathus- meaning "ample"; and νοτος -notos- meaning "back", for the very wide axis of the thorax.

The species names are derived as follows.