Cajetan Roos (1690 in Rome – 1770 in Vienna), was an Italian landscape painter of German descent.
According to the RKD he was the son and pupil of Philipp Peter Roos.Cajetan Roos in the RKD He signed his name "Rosa", "Gaetano Rosa" and "Gaetano de Rosa". He was the father of the painter Joseph Roos. Like his father and grandfather before him, he is known for Italianate landscapes with streams and cows, though after 1743-1744 he painted mostly religious works.
References
Gaetano de Rosa on Your paintings Cajetan Roos on Artnet