Longinos Navás (7 March 1858 Cabacés, Tarragona - 31 December 1938 Girona) was a Spanish entomologist who specialised in Plecoptera and Neuropteroidea.
Father Longinos Navás was a Jesuit priest. He published extensively on the Neuroptera fauna of Spain in Memorias de la Real. Academia Ciencias y Artes de Barcelona.His papers on worldwide fauna are published in this, other Spanish, German, Italian and American entomological journals.Navás described very many new species. His Neuroptera are in the Museu de Ciencias Naturals, Museum of Natural Sciences, Barcelona.His Lepidoptera collections are in Museo Paleontologico de la Universidad de Zaragoza, Zaragoza.