On the tribal classification of the Nearctic Melolonthinae (Coleoptera: Scarabaeidae), with descriptions of new species of Acoma Casey, 1889.

The subfamily Melolonthinae (Coleoptera: Scarabaeidae) is defined and characterized, and a brief summary of the world melolonthine tribes and their distributions are provided. Nearctic genera previously considered incertae sedis (Acoma Casey, 1889, Chaunocolus Saylor, 1937 and Chnaunanthus Burmeister, 1844, Phobetus LeConte, 1856, and Warwickia Smith Evans, 2005) are each placed in the proposed new tribes Acomini, Chnaunanthini, Phobetusini, and Warwickiini, respectively. Tribal assignments for all Nearctic melolonthine genera are presented.

Taxonomic review of Athliini (Coleoptera: Scarabaeidae: Melolonthinae), a new tribe of scarab beetles endemic to South America.

Athliini Smith Evans, new tribe (Coleoptera: Scarabaeidae: Melolonthinae) includes four genera that occur from southern South America through to the southeastern regions of Brazil: Apteroathlia Smith Evans, new genus, Athlia Erichson, 1835, Dihymenonyx Gutiérrez, 1949, and Ulata Saylor, 1945. Justifications are provided for the new tribe and for the placement each genus in the new tribe. Keys to genera and species are presented along with distributional data and maps for all species.