Dr. Velasquez pioneered in Philippine phycology. He made the first intensive study of the local Myxophyceae or the bluegreen algae and devoted at least 30 years of productive work in the study of Philippine algae from which he received local and international recognition. From laboratory assistant in the Department of Botany, University of the Philippines, he rose from the ranks until he became Professor in Botany in 1958. He was appointed Emeritus Professor when he retired in November 1967. Among his numerous honors are Distinguished Science Medal and Diploma of Honor from the Republic of the Philippines (1956), the John Simon Guggenheim Memorial Foundation Fellowship (1956-57). He is listed in the Men of Science, Division of Biological Sciences, (1969) World's Who's Who in Sciences (1970) and the Republic of the Philippines Cultural Heritage award (1972).