Charles Henry Tyler Townsend was born on December 5, 1863, in Oberlin, Ohio.

He was an American entomologist and author. From 1887 to 1891, he studied medicine at Columbian University (now George Washington University) in Washington, D.C. At the same time, he worked in the U.S. Department of Agriculture (USDA) as an assistant entomologist for Charles V. Riley (1843-1895). In 1891, he became a professor of zoology and entomology at the New Mexico College of Agriculture in Las Cruces. He collected and studied local insects, especially those that had the potential to become agricultural pests. He made notes on 400 insect species in New Mexico and authored 90 publications. In 1892, Townsend became curator of the Public Museum in Kingston, Jamaica, where he focused on educating the local farmers about insect pests and how to control them. In 1894, the USDA rehired him to study the appearance of a new pest, the cotton boll weevil, in Texas and northern Mexico. In 1899, he settled with his family in El Paso, Texas. Townsend and a partner started their own business, the Townsend-Barber Taxidermy and Zoological Company. After the death of his wife Caroline in 1903, he left his children with relatives and taught biology for two years at the Batangas Provincial School in the Philippines. In 1906, he returned to work for the USDA at a lab in Melrose Highlands, Massachusetts, studying potential parasites of the gypsy moth. He also completed his bachelor's degree from Columbia College. In 1909, Townsend was appointed entomologist and director of the Experiment Station in Piura, Peru. In 1914, he again worked for the USDA as a specialist on parasitic flies and curator of the Diptera collection at the U.S. National Museum. He completed his dissertation on the reproductive organs of the female fly and was awarded a doctorate degree by George Washington University. Due to the conflicts with his colleagues, he resigned and moved to Brazil, where the state government hired him to investigate agricultural pests and recommend methods for control. In 1923, he returned to Peru and became director of the Institute of Agriculture and Parasitology in Lima. He traveled along the Amazon River and wrote about his adventures in a series of travelogues published by a travel magazine in Buenos Aires. He returned to Brazil in 1929 and took a job as an entomologist at Fordlandia, an industrial community established by Henry Ford to manage a large rubber plantation and ensure a steady supply of rubber for the U.S. automobile industry. Townsend published his magnum opus on the muscoid flies, "Manual of Myiology" (1934-1942), consisting of 3760 pages in twelve parts.

In 1889, he married Caroline Wilhelmine Hess (1864–1901), and in 1908, he remarried Margaret Cecelia Dyer (1879–1947). He died on March 17, 1944, in Itaquaquecetuba, Sao Paulo, Brazil.