Characterization of Conserved MicroRNAs in Avocado Seed Weevils (Coleoptera: Curculionidae)

Avocado seed weevils are pests of quarantine importance that can limit avocado production and commercialization. However, the molecular regulatory mechanisms of these insects remain largely unexplored, and information on their microRNA (miRNA) repertoires is scarce. This study performed a reference-based, in silico characterization and comparative analysis of putative conserved miRNAs in three avocado seed weevils of agricultural importance: Conotrachelus perseae, Conotrachelus aguacatae, and Heilipus lauri. Total RNA was extracted from pooled adult specimens, and five small RNA libraries representing species-sex combinations were sequenced using Illumina technology. Putative miRNAs were predicted with miRDeep2 using the Leptinotarsa decemlineata genome, Tribolium castaneum mature and precursor miRNAs, and additional mature-miRNA references from five insect orders. After data curation, annotations with a miRDeep2 score ≥ 5 and ≥10 mature reads were retained. The final catalogue contained 31 mature miRNA annotations, of which 20 were detected in all libraries. Pairwise Jaccard indices ranged from 0.677 to 0.931. miR-276-5p had the highest compositional relative abundance in four libraries, whereas miR-8-5p predominated in female C. aguacatae. Because each species-sex combination was represented by one pooled library, the results do not demonstrate differential abundance or sex specificity. The identified miRNAs remain putative because their identity and function were not experimentally validated. These results provide an initial catalogue and candidates for future genomic, expression, and functional studies.