A review of Heteronyx Guerin-Meneville (Coleoptera : Scarabaeidae : Melolonthinae)

The genus Heteronyx Guérin-Méneville is defined and the 353 nominal Australian species are reviewed. Of the described species, 222 are shown to be valid (152 based on unique type specimens) and 111 names are synonomised. Four species are transferred to other genera. Lectotypes are designated and 28 extra Australian species are listed. Australian species are described and keys for identification provided. The possible reasons for the prolific speciation in Heteronyx are discussed. Genetic drift following the temporal and spatial isolation of small populations in a semi-desert environment, and/or isolation resulting from prolonged drought combined with local rainfall are suggested as causes.