ɐ kənˈɑːdɔnt, pɹˈɑːmɪssəm hæd ɐ pɹˈɪmᵻtˌɪv mˈaʊθ ˌʌndɚɹ ɪts ˈaɪz wɪð mˈɪnɚɹəlˌaɪzd tˈiːθ, wˌɪtʃ ɑːɹ bˈoʊθ tˈɪpɪkəl fɔːɹ kənˈɑːdɔnts.
A conodont, Promissum had a primitive mouth under its eyes with mineralized teeth, which are both typical for conodonts.