Eupolyphaga Chopard, 1929 is a cockroach genus mainly endemic to China. In this study, the species diversity of this genus is further explored through morphology and molecular analysis. Four species are described new to science: Eupolyphaga miracidia Qiu, sp. nov., Eupolyphaga udenostyla Qiu, sp. nov., Eupolyphaga reducta Qiu, sp. nov., and Eupolyphaga simila Qiu, sp. nov. New knowledge on some known species is added, including new distribution records and characteristics of females. Forty-five COI sequences were newly sequenced and a molecular species delimitation analysis was performed using ABGD method. Eighteen molecular operational taxonomic units were obtained by ABGD analysis, which are nearly consistent with the results of morphological delimitation.

The cockroach genus Eupolyphaga is revised. Twenty species and two subspecies are recognized, with thirteen species and two subspecies are new to science: E. daweishana sp. nov., E. dongi sp. nov., E. fengi sp. nov., E. hanae sp. nov., E. hupingensis sp. nov., E. maculata sp. nov., E. nigrifera sp. nov., E. nigrinotum sp. nov., E. pilosa sp. nov., E. robusta sp. nov., E. shennongensis sp. nov., E. wooi sp. nov., E. xuorum sp. nov., E. everestiana reni subsp. nov., and E. fengi yongshengensis subsp. nov. Homœogamia sinensis Saussure is placed as a junior synonym of E. sinensis (Walker) and the replaced name E. limbata (Kirby) for Homœogamia sinensis is invalid, the status of Eupolyphaga thibetana (Chopard) is recovered. Male genitalia of species in the genus is described and illustrated. Females and oothecae of some species are described and illustrated. Distribution maps and a checklist of Eupolyphaga are provided. A key to males of Eupolyphaga is given. Plenty habitat photographs are shown.

We investigated and described the thoracic structures, jumping mechanism, and promesothoracic interlocking mechanism of the click beetle Campsosternus auratus (Drury) (Elateridae: Dendrometrinae). Two experiments were conducted to reveal the critical muscles and sclerites involved in the jumping mechanism. They showed that M2 and M4 are essential clicking-related muscles. The prosternal process, the prosternal rest of the mesoventrite, the mesoventral cavity, the base of the elytra, and the posterodorsal evagination of the pronotum are critical clicking-related sclerites. The destruction of any of these muscles and sclerites resulted in the loss of normal clicking and jumping ability. The mesonotum was identified as a highly specialized saddle-shaped biological spring that can store elastic energy and release it abruptly. During the jumping process of C. auratus, M2 contracts to establish and latch the clicking system, and M4 contracts to generate energy. The specialized thoracic biological springs (e.g., the prosternum and mesonotum) and elastic cuticles store and abruptly release the colossal energy, which explosively raises the beetle body in a few milliseconds. The specialized trigger muscle for the release of the clicking was not found; our study supports the theory that the triggering of the clicking is due to the building-up of tension (i.e., elastic energy) in the system.

Seven new species of Ctenoneura Hanitsch, 1925, Ctenoneura bawangensis sp. nov., Ctenoneura delicata sp. nov., Ctenoneura elongata sp. nov., Ctenoneura heixuanfeng sp. nov., Ctenoneura helicata sp. nov., Ctenoneura papillaris sp. nov. and Ctenoneura qiuae sp. nov. are described from Hainan and Yunnan, China. Ctenoneura simulans Bey-Bienko, 1969 is redescribed and illustrated. Male genitalia of this genus is described and illustrated for the first time and is found to lack any genital hook. Female Ctenoneura is reported as apterous. Species abundance is estimated. Two species groups are suggested and the taxonomic status of the genus is discussed. A map and a key to males of Chinese Ctenoneura spp. and an updated checklist of the Ctenoneura are provided. Habitat photographs of Ctenoneura are shown for the first time.