DNA barcoding and phylogenetic analysis of dung beetles (Coleoptera: Scarabaeidae: Scarabaeinae) in North-Eastern Namibia

Abstract Taxonomical Keys have been used in the identification of dung beetle species due to their cost-effectiveness and accessibility. The aim of this study was to determine the DNA barcoding and phylogenetic relations of dung beetles in north-eastern Namibia. Sampling of dung beetles was done using baited pitfall traps. The collected Dung beetles were preserved in DNA/RNA Shield solution. The genomic DNA was isolated using blood and tissue Quick-DNA Miniprep Plus Kit. COI universal primers were used for PCR amplification. The sequence FASTA files were aligned using the multiple alignments ClustalW software, and the Phylogenetic relationships by neighbour-joining analysis were performed using the MEGA12 software. A total of 62 DNA barcodes of dung beetle species were accomplished, from which 15 species from 27 sequenced samples were identified with a percentage of 95–100%, while 35 dung beetle sequences were not retrieved from the database. The neighbour-joining phylogenetic tree showed 9 species of the genera Onthophagus , Milichus , and Caccobius of the tribe Onthophagini separated from each other and grouped together with the bootstrap value (> 95%). The clustering examination divided the 32 species into three main clades, while two species appeared separately from the three clades. This study was the first report of DNA barcodes specifically for Namibian dung beetles. The DNA barcoding and phylogenetic analysis application for molecular identification in dung beetles provides valuable and accurate information which is useful for understanding their diversity.