ɪn wˈʌn ˈɪnstəns, mətˈɪɹiəl wˈʌns ɹᵻfˈɜːd tə fˈoːɹ dʒˈɛnɚɹə ænd sˈɛvən spˈiːsiːz ɔnðə bˈeɪsɪs ʌv dˈɪfɹənsᵻz ɪn mˈoʊlɚ ʃˈeɪp ɪz nˈaʊ θˈɔːt tə ɹˌɛpɹᵻzˈɛnt dˈɪfɹəntli ˈeɪdʒd ˌɪndᵻvˈɪdʒuːəlz əvə sˈɪŋɡəl spˈiːsiːz, kɑːɹdˌaɪəθˈɜːɹiəm pˈæɹənˌɛns.
In one instance, material once referred to four genera and seven species on the basis of differences in molar shape is now thought to represent differently aged individuals of a single species, Cardiatherium paranense.