Formalization of the long-used name Andinotoxodon bolivarensis Madden (Toxodontidae, Notoungulata, Mammalia)

The name Andinotoxodon bolivarensis was originally proposed in an unpublished doctoral dissertation, rendering it nomenclaturally unavailable under the International Code of Zoological Nomenclature (ICZN). Despite this, the name has been consistently used in the scientific literature for over three decades, appearing in numerous studies on Neogene Toxodontidae. Here we make the name Andinotoxodon bolivarensis available for the first time, in compliance with Articles 8.1, 16.4, and 72.3 of the ICZN. We designate as holotype MNHN-Bol-V 3570, a nearly complete cranium with associated mandible, postcranial elements, and partial manus, from the Honda Group (Quebrada Honda, Tarija, Estado Plurinacional de Bolivia), dated to approximately 13.1–12.7 Ma. A new diagnosis is provided, distinguishing Andinotoxodon bolivarensis from all other toxodontid genera based on upper molar and mandibular morphology. Referred material from the late Middle to Late Miocene of Ecuador and Bolivia is also documented. The publication of this work satisfies the criteria of Article 23.2 of the ICZN by promoting nomenclatural stability of a name long-recognized by the paleontological community.