In Portugal, hereditary surnames were adopted according to fairly general rules and during the late Middle Ages, names that described a person's temperament or appearance were frequently used. Such nicknames sometimes became hereditary and were passed down as surnames onto further generations. The name Lopes is thought to be derived from the Latin word "lupus," meaning "wolf."
^ Filby, P. William, Meyer, Mary K., Passenger and immigration lists index : a guide to published arrival records of about 500,000 passengers who came to the United States and Canada in the seventeenth, eighteenth, and nineteenth centuries. 1982-1985 Cumulated Supplements in Four Volumes Detroit, Mich. : Gale Research Co., 1985, Print (ISBN 0-8103-1795-8)