DefinePK

Abstract

Ladybird beetles (Coccinellidae: Coleoptera) are vital for pest control and ecosystem balance, but their identification is hindered by morphological similarities. This study utilizes mitochondrial COI gene barcoding to profile Pakistani ladybird beetles for species identification and biodiversity assessment, focusing on the previously unsurveyed Bannu and Dera Ismail Khan divisions of Khyber Pakhtunkhwa, Pakistan during 2021-2022. A total of 40 COI sequences representing ten species from eight genera and three tribes of ladybird beetles were analyzed for DNA barcoding and phylogenetic studies. The obtained sequences were confirmed and compared with data from GenBank and BOLD. Phylogenetic trees were constructed using the maximum likelihood method. The COI sequences showed 94% to 100% similarity with corresponding ladybird beetle sequences in the databases. Out of 687 COI gene sequence positions, 315 (46%) displayed 80% pairwise identity, while 372 (54%) were variable. Among these, 324 (47%) sites were parsimony-informative, and 48 were singleton sites. Nucleotide frequency analysis revealed a higher AT content (69.2%) compared to GC content (30.8%). The sequences showed a mean intraspecific genetic divergence of 0.60% and a mean interspecific genetic divergence of 17.46%. A distinct barcode gap was observed between conspecific and congeneric species of ladybird beetles. Most tribes within the Coccinellidae family were monophyletic, with high bootstrap values ranging from 78% to 82%, and a mean divergence threshold of 0.01 ± 0.13. In conclusion, the study area hosts diverse ladybird beetle species, and COI gene barcoding is a reliable tool for their identification and biodiversity assessment.