Gualterio Looser Schallemberg (September 4, 1898, Santiago – July 22, 1982) was a Chilean botanist and engineer of Swiss parentage.[1] He owned a factory that made agricultural implements.
In 1928 Looser joined the American Fern Society, and started to publish papers on the pteridophytes of Chile.[2] His herbarium containing ca. 8000 specimens was given to Conservatoire et Jardin botaniques de la Ville de Genève.