Assessment of the phylogenetic relationships within the spondylidine branch of Spondylidinae (Coleoptera, Cerambycidae)

Abstract

Spondylidinae is a minor subfamily of Cerambycidae with around 100 species in 20 genera. The tribes Asemini and Spondylidini, both salient owing to vectors and invaders into the limelight of phytosanitary authorities, constitute the “spondylidine branch”. Although a few species of the branch were being included in some higher taxonomic level studies, the phylogenetic relationships within the taxa have never been evaluated from a molecular viewpoint. The present study identifies the phylogenetic relationships within the branch inferring from a single locus (COI) global dataset and two multi-locus local datasets, binary combinations of mitochondrial COI, 16S rRNA and nuclear 28S rRNA D1-D2, that sequences were obtained from the samples of the East of Marmara Region, Turkey. [(Spondylis+Neospondylis) + Megasemum] and [Tetropium+Asemum] groups were separated from the same node in the phylogenetic trees. The genus Cephalallus was stated on the basalmost of these two groups. Arhopalus split from all other genera and divided into two subgroups. There were discrepancies between morphology and COI barcode sequences, which might be a sign of hybridisation between A. rusticus and A. syriacus. Intraspecific distances of COI gene regions of S. buprestoides, As. striatum and T. cinnamopterum were up to 4.26%, 8.51%, and 6%, respectively, which might point out to cryptic speciation.