The predaceous beetle family Cleridae includes a large and widely distributed rapid radiation, which is vital for the ecosystem. Despite its important role, a number of problems remain to be solved regarding the phylogenetic inter-relationships, the timing of divergence, and the mitochondrial biology. Mitochondrial genomes have been widely used to reconstruct phylogenies of various insect groups, but never introduced to Cleridae until now. Here, we generated 18 mitochondrial genomes to address these issues, which are all novel to the family. In addition to phylogenomic analysis, we have leveraged our new sources to study the mitochondrial biology in terms of nucleotide composition, codon usage and substitutional rate, to understand how these vital cellular components may have contributed to the divergence of the Cleridae. Our results recovered Korynetinae sister to the remaining clerids, and the calde of Clerinae+Hydnocerinae is indicated more related to Tillinae. A time-calibrated phylogeny estimated the earliest divergence time of Cleridae was soon after the origin of the family, not later than 160.18 Mya (95% HPD: 158.18–162.07 Mya) during the mid-Jurassic. This is the first mitochondrial genome-based phylogenetic study of the Cleridae that covers nearly all subfamily members, which provides an alternative evidence for reconstructing the phylogenetic relationships.

To explore the characteristics of the mitogenome of Melyridae and reveal phylogenetic relationships, the mitogenome of Cordylepherus sp. was sequenced and annotated. This is the first time a complete mitochondrial genome has been generated in this family. Consistent with previous observations of Cleroidea species, the mitogenome of Cordylepherus sp. is highly conserved in gene size, organization and codon usage, and secondary structures of tRNAs. All protein-coding genes (PCGs) initiate with the standard start codon ATN, except ND1, which starts with TTG, and terminate with the complete stop codons of TAA and TAG, or incomplete forms, TA- and T-. Most tRNAs have the typical clover-leaf structure, except trnS1 (Ser, AGN), whose dihydrouridine (DHU) arm is reduced. In the A+T-rich region, three types of tandem repeat sequence units are found, including a 115 bp sequence tandemly repeated twice, a 16 bp sequence tandemly repeated three times with a partial third repeat and a 10 bp sequence tandemly repeated seven times. Phylogenetic analyses based on 13 protein-coding genes by both Bayesian inference (BI) and maximum likelihood (ML) methods suggest that Melyridae sensu lato is polyphyletic, and Dasytinae and Malchiinae are supported as independent families.

Complete mitochondrial genomes are valuable resources for phylogenetics in insects. The Cyphonoceridae represents an important lineage of fireflies. However, no complete mitogenome is available until now. Here, the first complete mitochondrial genome from this subfamily was reported, with Cyphonocerus sanguineus klapperichi as a representative. The mitogenome of C. sanguineus klapperichi was conserved in the structure and comparable to that of others in size and A+T content. Nucleotide composition was A+T-biased, and all genes exhibited a positive AT-skew and negative GC-skew. Two types of tandem repeat sequence units were present in the control region (136 bp × 2; 171 bp × 2 + 9 bp). For reconstruction of Lampyridae’s phylogeny, three different datasets were analyzed by both maximum likelihood (ML) and Bayesian inference (BI) methods. As a result, the same topology was produced by both ML analysis of 13 protein-coding genes and 2rRNA and BI analysis of 37 genes. The results indicated that Lampyridae, Lampyrinae, Luciolinae (excluding Emeia) were monophyletic, but Ototretinae was paraphyletic, of which Stenocladius was recovered as the sister taxon to all others, while Drilaster was more closely related to Cyphonocerinae; Phturinae + Emeia were included in a monophyletic clade, which comprised sister groups with Lampyridae. Vesta was deeply rooted in the Luciolinae.

Osphya Illiger (Melandryidae: Osphyinae) as a species-poor insect group, exhibits a widespread distribution in the Northern Hemisphere, however, the research of the genus is poorly documented especially in East Asia. Herein, an interesting species is discovered in Shennongjia National Natural Reserve (Hubei, China). The examination of morphological characters and comparisons with others show it to be a new member of Osphya, which is described under the name of O. sinensis sp. n. The characteristic photos and a key to the species of Osphya from East Asia are provided. Meanwhile, the mitochondrial genome of O. sinensis sp. n. is sequenced and annotated. Based on this obtained mitogenome and the publicly available data, we reconstructed the phylogeny of Tenebrionoidea by different cladistics methods to investigate the relationships between the new species with others. The results consistently recover O. sinensis sp. n. sister to O. bipunctata (Fabricius) with high supporting values, which further confirm the placement of the new species in the genus Osphya. This is the first time reporting the genus Osphya, the only representative genus of melandryid Osphyinae from mainland China, which enriches the diversity of beetles from the Chinese fauna at both generic and subfamilial levels.

A checklist of 166 species and subspecies from 62 genera, 15 subfamilies, 5 families and 2 superfamilies of Gryllidea, is recorded from Yunnan Province of China, based on the published data and accumulated material. The detailed distribution of most species is provided in Yunnan Province. Mitius eryuanensis Yuan, Xie & Liu sp. nov. is described as new species.