Branta rhuax is an extinct goose, or large gooselike bird, that used to live in the Hawaiian Islands. It was initially described into the monotypic genus Geochen but assigned to Branta by Storrs L. Olson in 2013 after reexamination of the subfossil material.
Species taxanomy provided by GBIF Secretariat (2022). GBIF Backbone Taxonomy. Checklist dataset https://doi.org/10.15468/39omei accessed via GBIF.org on 2023-06-13; License: CC BY 4.0