Class Mammalia Linnaeus, 1758 - mammals Subclass Boreosphenida Luo, Cifelli & Kielan-Jaworowska, 2001 - tribotherians see Clade Boreosphenida Luo, Cifelli & Kielan-Jaworowska 2001 Infraclass Eutheria Gill, 1872 Genus †Montanalestes Cifelli, 1999