Rhinichthys, known as the riffle daces, is a genus of freshwater fish in the carp family (Cyprinidae) of the order Cypriniformes. The type species is Rhinichthys atratulus, the blacknose dace. Rhinichthys species range throughout North America. The riffle daces are a basal lineage in an insufficiently resolved clade of American Leuciscinae. Such a group had been proposed on anatomical evidence, and was verified using mtDNA 12S rRNA sequences.(Simons & Mayden 1997)