Miobdelus humilis sp. nov. is described as new. A lectotype is designated for Staphylinus (Xanthocypus) miwai Bernhauer, 1943 and Thoracostrongylus miyakei Bernhauer, 1943. Ocypus (Ocypus) miwai (Bernhauer, 1943) is transferred from Ocypus Leach, 1819 to Sphaerobulbus Smetana, 2003 and the species is re-described based on types and modern specimens. A female description of Apecholinus imitator Smetana & Hu, 2019 is provided. Creophilus flavipennis Hope, 1831, Nelmanwaslus ornatus Smetana, 2006, Ontholestes oculatus (Sharp, 1874) and Platydracus juang Smetana, 2005 are reported for the first time from Taiwan. Ontholestes oculatus is re-described based on Taiwanese material, representing the first record of the genus Ontholestes Ganglbauer, 1895 in Taiwan. Platydracus juang is considered to be a termitophilous species, associated with Reticulitermes leptomandibularis (Hsia & Fan, 1965), which would represent the first report of termitophily in the subtribe Staphylinina. Additional records of C. maxillosus maxillosus (Linnaeus, 1758), Agelosus auricomus Smetana & Hu, 2019, Apecholinus fraternus Fairmaire, 1891, Miobdelus taiwanensis taiwanensis Smetana, 2001, Naddia taiwanensis Shibata, 1979 and Thoracostrongylus formosanus Shibata, 1982 are provided. Habitus photos of the above species and Dinothenarus choui Smetana, 1992 are also provided. A preliminary checklist of Staphylinina in Taiwan is proposed.

Zoraptera shows extreme uniformity in general body morphology, with the exception of Formosozoros (=Zorotypus) newi Chao & Chen, 2000, which stands out in terms of the shape and arrangement of its legs, the cerci, and several other morphological characters. After critical evaluation, we found that this species is not a zorapteran but is instead a nymph (1st instar) of an earwig; i.e., F. newi is a dermapteran. Because of the lack of morphological descriptions of Dermaptera nymphs that would allow species identification, and because the type material of F. newi is lost, a more detailed classification is not possible. We therefore propose that the genus name Formosozoros Chao & Chen, 2000 and the species name Formosozoros newi Chao & Chen, 2000 are nomina dubia.

Aeshnidae Rambur, 1842 are impressive large insects distributed worldwide. Currently, over 500 species are recognized. Nevertheless, the phylogeny of this family is not completely understood. We applied molecular phylogenetic analysis using two popular phylogenetic markers, the mitochondrial COI gene fragment (barcoding sequence) and the nucleic ITS region, containing the ITS1, 5.8S rRNA, and ITS2 sequences. We used available and credible published sequences and 96 newly sequenced specimens. Our analysis involved all West Palaearctic species, all but one genera of the Holarctic Aeshnidae, and most genera worldwide, and is by far the largest molecular study of this family. The topology of all trees created with different algorithms and genes is in favour of the current taxonomic concept, with some remarkable outcomes. Aeshna Fabricius, 1775, was found to be diverged into several branches, especially with respect to the COI gene. Although it appeared not monophyletic in phylogenetic reconstructions based on the ITS region, the analysis of COI and joint analysis suggest its monophyly in the current taxonomical sense, with one notable exception. Aeshna isoceles (Müller, 1767) has fallen out of Aeshna in all analyses, so a new monophyletic genus, Isoaeschna gen. nov. is introduced for it. The genus Brachytron Evans, 1845 tightly clustered with Aeschnophlebia Selys, 1883, Epiaeschna Hagen in Selys, 1883, and Nasiaeschna Selys in Förster, 1900. Thus, we suggest subsuming these four genera under the priority name Brachytron. Tetracanthagyna Selys, 1883 clusters as expected with Brachytron in the ITS tree, but is an independent ancient clade of its own in all COI trees. The genus Polycanthagyna Fraser, 1933 syn. nov. is synonymised to Indaeschna Fraser, 1926. On the species level, we suggest that the American Aeshna septentrionalis Burmeister, 1839 be treated as a subspecies of A. caerulea (Ström, 1783), Aeshna caerulea septentrionalis. We synonymize Gynacantha hyalina Selys, 1882 with Gynacantha subinterrupta Rambur, 1842. Our analysis provides new insights on the tight relationships of the circumboreal species Aeshna juncea and A. subarctica and the intraspecies phylogeny of Aeshna juncea.

The Oriental pselaphine genus Horniella Raffray, 1905 currently contains 29 species. In this paper, six new species are described: H. nantouensis Zhang, Hu & Yin, sp. nov. and H. taiwanensis Zhang, Hu & Yin, sp. nov. from Taiwan, China; H. bifurca Zhang & Yin, sp. nov. and H. haucki Zhang & Yin, sp. nov. from Thailand; H. khasiensis Zhang & Yin, sp. nov. from northern India; and H. sabahensis Zhang & Yin, sp. nov. from eastern Malaysia. In addition, H. aculeata Yin & Li, 2015, originally described from Yunnan, China, is newly recorded from Thailand.