The taxonomic status of beadgall forming mites on Acer campestre and pseudoplatanus is currently unclear and quite confusing. The European gall site Bladmineerders lists at least three species: Aceria cephalonea on A campestre and pseudoplatanus, Aceria macrorhyncha on A pseudoplatanus and "rarely" on A campestre, and Aceria myriadeum on A campestre. Amrine, however, lists both Aceria macrorhyncha and Aceria cephalonea as junior synonyms of A myriadeum, implying there is one mite responsible for a range of upper-leaf bead and nail gall forms on both hosts.

For the moment, our taxonomy follows the Amrine catalog, while IDs on iNaturalist largely follow Bladmineerders. However, note that while galls similar to images Bladmineerders presents as Aceria cephalonea have been observed on Acer pseudoplatanus in North America, to our knowledge no anatomical IDs have been made of the mites on either Acer species outside of Europe. Any ID made of galls here is thus doubly uncertain.

- Gallformers Contributors: (2024) Gallformers ID Notes^©