Thallostoma is a genus of moths belonging to the family Tineidae. It contains only one species, Thallostoma eurygrapha, which is found in New Zealand. The wingspan is 18–19 mm. The forewings are elongate and dark purplish-fuscous with whitish-ochreous markings. The hindwings are grey.
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