Rhadinosteus parvus is an extinct genus of prehistoric frog.Present in Stratigraphic zone 6. Found at the Rainbow Park site in Utah's Dinosaur National Monument. A pipoid frog whose generic name means "slender bone." It may have been a member of the rhinophrynidae. Only about 42 mm (1.6 inches) long in life. The R. parvus binomen means "small slender bone." Known from several slabs of rock which contain multiple partial specimens in association.