Species are not only the fundamental units of taxonomy but also the basic units of pest management. Insects of Conogethes are important agricultural and forestry pests. However, species boundaries within Conogethes often appear obscure. In the present study, we re-evaluated the species status of Conogethes by applying three species delimitation approaches based on the mitochondrial DNA sequences, with particular emphasis on the yellow peach moth C. punctiferalis (Guenée, 1854). We first optimized species delimitation and inter-species genetic divergence threshold using a DNA barcoding dataset. The results revealed that several nominal species of Conogethes species harbored deeply diverged mitochondrial lineages which were recognized as independent species by the species delimitation methods. The p-distance between the delimited putative species ranged from 0.0159 to 0.1321 with a mean of 0.0841. Then we refined the species status of C. punctiferalis using the smallest interspecific distance threshold based on a geographically comprehensive population-scale dataset. This procedure narrowed the species concept of C. punctiferalis to a genetically coherent unit. Further investigation of its intraspecific divergence in the geographic context revealed that the refined C. punctiferalis was still widely distributed with the same or highly similar mitochondrial haplotypes occurring across South and East Asia.

The genus Diomus Mulsant, 1850 (Coleoptera: Coccinellidae: Diomini) from China is herein revised. Five species of Diomus are occurring in the Chinese fauna to date, including a new species from the Dafushan Mountains Forest Park, Guangzhou, Guangdong, namely D. dafushanensis Bi, Peng & Chen, sp. nov. Nomenclatural history, diagnosis, illustrations and distribution were provided for each species. A key to the native species of Diomus from China is also presented.