关键词: 海南岛, DNA条形码, 尼蠓属, 捕食蠓, 分类

Abstract: Objective To identify and morphologically characterize six Nilobezzia males collected from Haikou, China using DNA barcoding. Methods A morphologically non-invasive method was used to extract genomic DNAs from the six Nilobezzia males. Slide specimens were made subsequently, and the cytochrome c oxidase subunit Ⅰ (COⅠ) gene was subjected to polymerase chain reaction (PCR) amplification and sequencing. Species identification was performed using the basic local alignment search tool (BLAST) by aligning sequences with the National Center for Biotechnology Information database and constructing a phylogentic tree based on neighbor-joining method. Major morphological features were photographed, measured, and sketched. Results DNA barcodes of the six Nilobezzia males were sequenced (sequence accession: PP351822-PP351827), showing a high sequence similarity (ranging from 97.72% to 99.85%) with the specimens of N. bamenwana females. The constructed neighbor-joining tree indicated that the six sequences of Nilobezzia males and three sequences of N. bamenwana were clustered into one branch, with a support rate of 100%. Therefore, the six Nilobezzia males were identified as N. bamenwana. Morphological features included: scutellum with 9 large setae, mid- and hind-foot thighs, tibiae, and tarsomeres with obviously long bristles, tergite Ⅸ with a sclerotized Ⅴ -shaped area, gonostylus straight and parameres completely fused. The slide specimens of the newly identified males were kept in the Insect Collection of the School of Tropical Agriculture and Forestry, Hainan University. Conclusion For the first time, N. bamenwana males have been identified using DNA barcoding techniques and their morphological features have been characterized.

Key words: Hainan Island, DNA barcode, Nilobezzia, Predaceous midge, Taxonomy