Aulacostephanidae is an extinct ammonoid cephalopod family belonging to the superfamily Perisphinctoidea. These fast-moving nektonic carnivores lived during the Upper Jurassic period, in the Kimmeridgian age.
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