Comparative Mitogenomics of Four Anomala Species and a Phylogenetic Reassessment of Scarabaeidae

Abstract

Background: The genus Anomala is exceptionally species-rich and includes many species recognized as major agricultural and forest pests. Nevertheless, the taxonomic status of certain species remains contentious, and the phylogenetic relationships within the genus are still poorly resolved and in need of further investigation. Objectives: To better elucidate the evolutionary relationships among these insects, we assembled the complete mitochondrial genomes (mitogenomes) of four Anomala species—A. aulax, Anomala sp., A. vitalisi, and A. xantholoma. Multiple molecular datasets were integrated to reconstruct the phylogenetic framework of Scarabaeidae. Methods: Wild adult specimens of four Anomala species were collected. After total DNA extraction, complete mitogenomes were assembled and annotated for comparative analysis of core genomic traits. Multiple datasets were applied to construct phylogenetic trees via maximum likelihood and Bayesian inference, so as to evaluate the evolutionary characteristics of each taxon. Results: Our analyses reveal that the mitogenomes of Anomala species exhibit a conserved architecture, characterized by similarities in genome size, AT nucleotide bias, and gene order, suggesting a high degree of evolutionary stability within the genus. The resulting phylogenetic trees robustly support the monophyly of the following families: Passalidae, Lucanidae, Geotrupidae, Trogidae, Hybosoridae, and Glaphyridae. Additionally, the phylogenetic findings revealed the paraphyly of both Scarabaeidae and Anomala, and further suggested that Melolonthinae is likely a paraphyletic group. Conclusions: This study enriches the currently available mitogenomic data and provides a preliminary foundation for understanding the phylogeny, resource conservation, and genetic diversity of Anomala.