ɹˈiːsənt məlˈɛkjʊlɚ fˌaɪloʊdʒnˈɛɾɪk stˈʌdiz ɹˈɛkəɡnˌaɪz ɐ klˈoʊs ɹᵻlˈeɪʃənʃˌɪp bᵻtwˌiːn hˈaɪdɹətʃˌoʊɚɹəs ænd kˈɛɹɑːdən, səpˈoːɹɾɪŋ plˈeɪsmənt ʌv bˈoʊθ dʒˈɛnɚɹə ɪn ɐ sˈʌbfɐmˌɪli ʌv kˈævɪˌɪdiː.
Recent molecular phylogenetic studies recognize a close relationship between Hydrochoerus and Kerodon, supporting placement of both genera in a subfamily of Caviidae.