three families. At least three extinct families are also recognised. † Allomyidae Aplodontiidae – mountain beaver † Mylagaulidae Sciuridae – squirrels,...

†Ischyromyoidea Family †Ischyromyidae Superfamily Aplodontoidea Family †Allomyidae Family Aplodontiidae: mountain beaver Family †Mylagaulidae Infraorder...

†Microparamyinae Wood 1962 Family †Theridomyidae Alston 1876 Family †Allomyidae Marsh 1877 Family †Mylagaulidae Cope 1881 Family †Reithroparamyidae Wood...