In this study, we report the complete mitogenome of Nothrus silvestris Nicolet, 1855 (Acari, Oribatida, Nothridae) sequenced from Illumina sequencing data. The full length of this mitogenome is 14,592 bp with the nucleotide composition A (41.0%), C (22.2%), G (13.1%), and T (23.7%). The N. silvestris mitogenome comprises 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes, and a non-coding control region. To elucidate the phylogenetic position of N. silvestris, a phylogenetic tree of 77 mite species were analyzed by maximum likelihood (ML) methods. According to phylogenetic analysis based on 13 protein-coding genes of mitogenomes, N. silvestris and Nothrus reticulatus were found the most basal Crotonioidea in the given dataset. This mitogenome not only enriches the genetic information of Nothridae, but also will be useful in the phylogenic and evolutional studies on oribatid mites.

Four new species, Balaustium allomedicagoense sp. nov., Balaustium neomedicagoense sp. nov., Balaustium pseudomedicagoense sp. nov. and Neoabrolophus guizhouensis sp. nov. are described and illustrated based on adults. B. allomedicagoense sp. nov. and N. guizhouensis sp. nov. are from the Yunnan-Guizhou Plateau. The genus Balaustium is firstly recorded for the Oriental realm and the genus Neoabrolophus is recorded for the first time from China. B. neomedicagoense sp. nov. collected from the Xizang Zizhiqu (Tibet Autonomous Region), and B. pseudomedicagoense sp. nov. collected from Qinghai Province, where is known as the Qinghai-Tibetan Plateau, an unique geographical unit with the highest altitude in the world, while B. allomedicagoense sp. nov. from Yunnan Province indicates Balaustium distribution in Oriental realm. A checklist of species of the genus Balaustium is given.