On the name of the lepidophagous characid fish Roeboexodon guyanensis (Puyo) (Teleostei: Characiformes: Characidae)

The arguments for the usage of the names Gnathoplax, Roeboexodon, R. geryi, and R. guyanensis are revised. Based on the literature and museum specimens, we recommend that the neotype of Exodon guyanensis should be considered valid; that the genus Gnathoplax should be considered an objective junior synonym of Roeboexodon; and that Roeboexodon geryi should be considered an objective junior synonym of Exodonguyanensis.

Os argumentos para o uso dos nomes Gnathoplax, Roeboexodon, R. geryi e R. guyanensis são reavaliados. Baseados na literatura e em espécimes de museu, recomendamos que o neótipo de Exodonguyanensis seja considerado válido, que o gênero Gnathoplax seja considerado sinônimo objetivo júnior de Roeboexodon e que Roeboexodon geryi seja considerado sinônimo objetivo júnior de Exodon guyanensis.

The manuscript benefited from comments by Maria Isabel Landim, Naércio Menezes, Richard Vari, and Mônica Toledo-Piza. We are grateful to Guy Duhamel and Patrice Pruvost (MNHN) for the loan of material in their care, to David Catania for hospitality and assistance during the stay of CRM in the California Academy of Sciences funded by the Lakeside Foundation. Maria Isabel Landim assisted in the translation of the papers of Puyo and Géry, and Ubirajara Martins assisted on the question of the validity of the Géry's neotype. Finally we thank Carlos Lucena for discussions on the Roeboexodon/Gnathoplax problem