Class Mammalia Linnaeus, 1758 - mammals Subclass Boreosphenida Luo, Cifelli & Kielan-Jaworowska, 2001 - tribotherians see Clade Boreosphenida Luo, Cifelli & Kielan-Jaworowska 2001 Family †Kermackiidae Butler, 1978, incertae sedis Genus †Trinititherium Butler, 1978 [monotypic] †Trinititherium slaughteri Butler, 1978