The genus Theraphosa was established by Thorell (1870) as the type genus of the simultaneously published family Theraphosidae, the most diverse group of mygalomorph spiders. This authorship and publication date have long been accepted by the majority of authors. However, there has been a long-standing minority view that the genus name should be attributed to Walckenaer (1805), and the publication date of the family name changed to 1869.
 A thought-provoking recent publication has examined this case. Based on a limited selection of the relevant literature, the authors struggled to make sense of their sources and prematurely concluded that the minority opinion might indeed be correct. They overlooked the potentially destabilising implications of this reattribution.
 This paper revisits the evidence in the light of a much wider range of relevant publications, places it in its important historical context and, on the basis of the current rules of nomenclature, concludes that the traditional consensus has indeed been correct.
 Thus, Theraphosa Thorell, 1870 is the type genus of Theraphosidae Thorell, 1870 and a nomen protectum, while Theraphosa Schinz, 1823 is a nomen oblitum, mostly limited to the German textbook literature of the early 19th century. Teraphosa Eichwald, 1830 and Teraphosa Gistel, 1848 are junior synonyms of Avicularia Lamarck, 1818 (syn. nov.). Theraphosa Walckenaer, 1805 is a suprageneric name of the class-series (synonymous to Mygalomorphae) and not available at the genus level.