Callostracon sensu F. Nordsieck, 1972 (ncorrect subsequent spelling of Colostracon Hamlin, 1884; not an available name) Callostracon is a genus of small sea snails, predatory marine gastropod mollusks in the family Acteonidae, the barrel bubble snails.

[1] When they described Callostracon tyrrhenicum, Smriglio & Mariottini combined the specific epithet with Callostracon as used by Nordsieck (1972).

The latter, however, is a misspelling of Colostracon Hamlin, 1884, a genus of Mesozoic caenogastropods unrelated to the Recent Mediterranean species.

Recognizing this situation, Repetto & Bianco established the name Callostracon for the Mediterranean species.

Callostracon Repetto & Bianco, 2012, is not a junior homonym of "Callostracon" as used by Nordsieck, as the latter is an incorrect subsequent spelling, and thus not a nomenclaturally available name.