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Hesperentomon bolense sp. n., described from Northwest China, is distinguished from other Hesperentomon spp. by having foretarsal sensillum b clearly shorter than c, a robust sensillum c broader than the other foretarsal sensilla, 18 posterior setae on the mesonotum and 16 posterior setae on the metanotum, 12 posterior setae on urotergites II–VI (P1a and P2a absent), 8 posterior setae on urosternites IV–VI (Pc absent), and absence of seta P2a on urotergite VII. The morphological characters of all described species of Hesperentomon are compared, and an updated identification key to species is given. The DNA barcodes of H. bolense sp. n. were compared to similar species of the genus; the K2P genetic divergences were 0–5.1% between individuals of H. bolense sp. n., but 21.4%–27.3% between H. bolense sp. n. and other congeneric species. The molecular data further confirmed H. bolense as a distinct species.

A new genus Songius is established and two new species--Songius rugosus from Qixia Mountain and Laoshan Forest Park, Jiangsu, and Tiantangzhai, Dabie Mountain, Anhui, and Songius bicruris from Tiantangzhai--are described. A novel surface structure of the pygidial tergum was observed by scanning electron microscopy. The genus is established on the basis of the distinctive appearance of the modification of the surface structure of the pygidial tergum.

The phylogenetic interrelationships among four hexapod lineages (Protura, Collembola, Diplura and Insecta) are pivotal to understanding the origin of insects and the early diversification of Hexapoda, but they have been difficult to clarify based on the available data. In this study, we identified 91 conserved microRNA (miRNA) families from 36 panarthropod taxa, including seven newly sequenced non‐insect hexapods. We found major clade differentiation accompanied by the origin of novel miRNA families, and most miRNA clusters are conserved with a high degree of microsynteny. Importantly, we were able to identify two miRNA families unique to Hexapoda, and four miRNA families and a miRNA cluster that exist exclusively in Diplura and Insecta, suggesting a close relationship between Diplura and Insecta as well as the monophyly of Hexapoda. Combined with a phylogenetic analysis based on the presence/absence matrix of miRNA families, our study demonstrates the effectiveness of miRNA in resolving deep phylogenetic problems.