Class [Mammalia] Linnaeus, 1758 - mammals Order Rodentia Bowdich, 1821 - rodents Family Heteromyidae Gray, 1868 - pocket mice, kangaroo rats, and kangaroo mice Genus Dipodomys Gray, 1841 - kangaroo-rats Dipodomys merriami Mearns, 1890 - Merriam's kangaroo-rat