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]
         1 †Trinititherium slaughteri Butler, 1978