Mitochondrial Genome Comparison and Phylogenetic Variety of Four Morphologically Similar Bamboo Pests.

Abstract

Bamboo snout moths (Lepidoptera, Crambidae) comprise the four species: Eumorphobotys obscuralis, Circobotys aurealis, Demobotys pervulgalis, and Crypsiptya coclesalis. These economically important insect pests of bamboo are widely distributed in tropical and subtropical regions. The lack of precise mitochondrial genetic data has impeded the development of effective identification techniques, accurate classification strategies, and targeted prevention and treatment strategies. In this study, we obtained the complete mitochondrial genome sequences of four bamboo snout moth species using high-throughput sequencing. The mitogenomes were 15,103-15,349 bp in length and contained 13 protein-coding genes, 22 transfer RNA genes (tRNAs), two ribosomal RNA genes (rRNAs), and a noncoding region (A + T rich element), consistent with previously studied Crambidae mitogenomes. We reconstructed the phylogenetic relationships among the four species using Bayesian inference and maximum likelihood methods. The moths that fed on bamboo were well clustered in a single clade. Crypsiptya coclesalis was most closely related to D. pervulgalis, while E. obscuralis was most closely related to C. aurealis. The divergence among the main lineages of 97 Lepidoptera species was reconstructed using an uncorrelated relaxed molecular clock. Analyses of the phylogenetic relationships and divergence times showed that the evolution of lepidopteran species has been closely related to that of their hosts. The data support the development of molecular identification techniques for the four species of bamboo snout moth, and our results provide a basis for targeted control strategies.