Molecular identification of immature Cerambycinae (Coleoptera: Cerambycidae): revisiting the significance of immature morphologies

The microstructure of immature insect forms plays a crucial role in systematics, especially in inferring phylogenetic relationships and designating the morphological basis for taxonomic units. However, the microstructure of longhorn beetle larvae and pupae is poorly understood, owing to difficulties in obtaining them and technical limitations. Among 90 larvae and 80 pupae collected and photographed, 31 larvae and 15 pupae remained unidentified after morphological and bionomical evidence-based identification. Cytochrome c oxidase I sequences were amplified successfully from 68 larvae and 59 pupae. Molecular identification using tree-based analysis identified 28 of 31 undetermined larvae (90.3%) and 14 of 15 undetermined pupae (93.3%) to the species level. We highlight the usefulness of DNA barcoding in identifying immature forms of cerambycid beetles and filling gaps in public databases. This study also demonstrates how microstructure can clarify the morphological basis of polyphyletic taxa on the phylogeny and emphasizes the significance of the microstructure of immature stages in longhorn beetle systematics.