DNA barcoding and the genetic diversity of scale insects (Hemiptera: Coccomorpha) found in Hainan Province, China

Scale insects (Hemiptera: Coccomorpha) can be significant pests of crop and ornamental plants globally, with many species posing threats to agriculture and forestry. Despite some research on scale insects in Hainan Province, China in the past, the scale insect species diversity and genetic variation remain poorly understood. Accurate species identification is crucial for biodiversity conservation and pest management. Using mitochondrial COI sequences for DNA barcoding, this study provides a comprehensive survey of the scale insects found in Hainan Province Samples were collected from 19 regions in Hainan Province, and the COI gene was sequenced from 456 individuals belonging to the families Diaspididae, Pseudococcidae, Coccidae and Monophlebidae. Sixty species from 34 genera were identified, including one new country record for China (Ferrisia dasylirii (Cockerell)), and 21 species are recorded from Hainan Province for the first time. The study also assesses the effectiveness of DNA barcoding for species identification and, for Hainan Province, records the geographical distribution, host preferences, and genetic diversity of these insects. The results provide valuable insights for the improvement of pest management strategies in the region.