Tardigrades are known for their ability to adapt to living in extreme environments. One such environment in which these invertebrates are found is cryoconite holes – water-filled holes located on the surface of glaciers. In the present study, samples were obtained from cryoconite holes from the Sven glacier (Spitsbergen), and an analysis of the species composition of tardigrades was carried out. In the collected samples, four taxa were found: Fontourion glaciale (Zawierucha, Buda and Gąsiorek, 2020), Acutuncus mariae Zawierucha 2020, Grevenius cryophilus Zawierucha, Buda, Novotná Jaroměřská and Gąsiorek, 2020 and Hypsibius sp. (Svenbreen). Morphological analysis revealed that differences between our specimens of the Hypsibius sp. (Svenbreen) and already described representatives of the genus Hypsibius are very clear and suggest that ours belong to species new to science. However, due to lack of genetic data formal description of the new species is not possible in present paper.

In this work morphological and molecular variability of seven populations of Jensenonchus sphagni (Brzeski, 1960) from Vietnam and Poland were studied. As a consequence, hereby we report the first occurrence of this species in Vietnam and at the same time in the Asian continent. The first report and description of males of this species are also provided. Additionally, the small and large subunit ribosomal DNA (18S and 28S rDNA) and the mitochondrial cytochrome c oxidase subunit I (mtCOI) sequences were acquired for the first time for this species and genus. Moreover, the obtained results of the phylogenetic analyzes question the current systematic position of J. sphagni and suggest its transfer from the subfamily Iotonchinae (fam. Iotonchidae) to the subfamily Prionchulinae (fam. Mononchidae).

New data on the stonefly of the genus Phanoperla Banks, 1938 is provided from Laos. P. laos sp. nov. is described as new to science based on a male specimen from Houaphan Province which is located in the northern part of Laos. Additionally, Phanoperla uchidai Sivec and Stark, 2010 and P. vietnamensis Zwick, 1986 are reported from Laos for the first time.

The poorly known antlion genus Cuca Navás, 1923, is revised, including the redescription of the type species C. impressa Navás, 1923, and the description of a new species Cuca racha sp. nov. from Vietnam. The two species differ in wing shape and chaetotaxy of female genitalia. The genus Cuca is, to date, only present in Vietnam.

Ferecis mariaclara gen. et sp. nov. (Ciinae: Ciini) is described based on specimens from a single field collection in the Cerrado biome of the state of Minas Gerais, in the Southeast Region of Brazil. The new genus is mainly characterized by lateral pronotal carinae visible only from below, a long prosternum in front of the procoxae (about 1.35× as long as the prosternal process), the apex of the protibiae without spines, with the outer apical angle produced to form a stout tooth in both sexes, and the diverging apical sutural flange of the elytra.

Third instar larva and pupa of Cnemida leprieuri Arrow, 1899 and third instar larva of Cnemida retusa (Fabricius, 1801) (Coleoptera, Scarabaeidae, Rutelinae) are described and illustrated based on specimens collected within rotten logs in North Brazil. The pupation of C. retusa is discussed. Third instar larvae of both species are compared with the only formerly known larva to the genus: Cnemida intermedia Bates, 1888. Formerly disponible generic keys to the third instar larvae and to pupae of New World Rutelini are updated. A key and a comparative study of chaetotaxy to known third instar larvae of Cnemida are also provided.

Two new species of the genus Lebia (s.l.) Latreille, 1802 are described: Lebia akinobuella Kirichenko-Babko, Kopeć et Krzemiński sp. nov., and Lebia baehri Kirichenko-Babko et Perkovsky sp. nov., from Baltic and Rovno ambers, respectively. Both described species belong to the subtribe Lebiina Bonelli, 1810, and exhibit similar morphological characters to representatives of the genus Lebia (s.l.). Illustrations are provided and the morphological characters of these fossil species and extant species from the subgenera of Lebia is discussed. The presence of aposematic coloration preserved in the two new fossil Lebia species is discussed and tentatively considered as an anti-predator strategy.

A new species, Anthrenus canadalunai is described and imaged. The new species is compared with two cofounding species: A. angustefasciatus Ganglbauer, 1904 and A. mroczkowskii Kalik, 1954. Images of the habiti, antennae, aedeagi, and sternite IX are presented. The new species is separated from A. angustefasciatus and A. mroczkowskii based on aedeagal and sternite IX structure. Following on from this, external features, such as colour pattern, are identified facilitating identification. The distributions of all three species are presented and discussed.

The tenebrionid genus Bolitonaeus Lewis, 1894 (type species: Bolitonaeus mergae Lewis, 1894, by original designation) (Tenebrioninae: Bolitophagini Kirby, 1837) contains a couple of species in the southern Palaearctic Region (Japan, southern China, Nepal) and is speciose in the Oriental Region including Halmahera, but lacks representatives in New Guinea and the Papuan Region. Newly collected specimens from the Cameron Highlands in the Malay Peninsula yielded a previously unrecognized species, being described herein. Added is a checklist of all known species of Bolitonaeus with new records.

In the present paper two new species from the subfamily Lagriinae Latreille, 1825 are described and illustrated: Bothrionota anichtchenkoi sp. nov. (Mindanao) and B. visayas sp. nov. (Samar). First recent available material since 1931 is presented for B. ruzzieri Telnov, 2022. A brief discussion on the distribution and morphological features of Bothrionota Borchmann, 1936 is provided.

Ctenoplectron solomonis sp. nov. from Guadalcanal, the first representative of Melandryidae Leach, 1815 from the Solomon Archipelago, is described and illustrated. Callidircaea Champion, 1916 stat. restit. is removed from synonymy with Megapselaphus Gemminger in Gemminger & Harold, 1870. Two new combinations are proposed: Ctenoplectron venustus (Champion, 1895) comb. nov. and C. lignivorus (Lea, 1896) comb. nov. (both from Callidircaea). Taxonomy and morphological features of Callidircaea, Ctenoplectron Redtenbacher, 1868, and Megapselaphus are discussed. Megapselaphus is hypothesized to be a senior synonym of Ctenoplectron. Callidircaea sexnotata, the type species of its genus, is illustrated for the first time.

The genus Microichthyurus Pic, 1919 from the Himalayan area is reviewed. Two new species are described, including M. flavifemur sp. nov. and M. nigripes sp. nov. (China: Yunnan and Xizang). They are illustrated with habitus and genital segments of both sexes and aedeagi. An identification key and a distribution map of Microichthyurus species from Himalayan area are provided.

Two new species of biting midges, Forcipomyia (Forcipomyia) arcuatilis sp. nov. and Forcipomyia (Saliohelea) sternaspina sp. nov. are described based on specimens collected respectively from the Dooars, and Sub-Himalayan region of West Bengal, a part of Himalaya Biodiversity Hotspot, India. In addition, we provide the first record of seven species belonging to the subgenera Caloforcipomyia Saunders, Euprojoannisia Brèthes, Forcipomyia s. str. and Pedilohelea de Meillon and Wirth from different areas of West Bengal, India. An updated key to the subgenera of Forcipomyia from India and a world key to the species of the subgenus Saliohelea are also provided.

A new species of the genus Crematogaster Lund, 1831, C. abouzeidi sp. nov. is described from Yemen based on the worker caste. The new species resembles the Afrotropical C. flaviventris Santschi, 1910, thus previous records of C. flaviventris from Yemen may be mis-identified and need to be re-examined. Crematogaster ghoneimi Sharaf & Aldawood, 2022, previously known only from Saudi Arabia, is recorded for the first time from Yemen. Specimens were collected in an urban garden, raising the possibility of being brought to the site nesting in imported plants. A Synoptic list of the Crematogater species of Yemen is provided.

The new genus Eotemnothorax gen. nov. is established for the former Temnothorax Mayr, 1861 species from late Eocene European ambers. Workers and queens of Eotemnothorax gen. nov. resemble those of Temnothorax but differ by the absence of a medial clypeal carina; in addition, all queens and some workers examined have distinct simple spur on the meso- and/or metatibiae. Males of the described genus are clearly differentiated from Temnothorax by a filiform antennal funiculus without an apical club, a short scape, a short and thick 1^st funicular segment, and a long and thin 2^nd segment. At the same time, they are well distinguished from the males of the Leptothorax genus group (i.e., Leptothorax Mayr, 1855, Harpagoxenus Forel, 1893 and Formicoxenus Mayr, 1855) by 13-segmented antennae and subtriangular mandibles with a clearly defined masticatory margin with four sharp teeth. Temnothorax gracilis (Mayr, 1868), T. petiolatus (Mayr, 1868), T. glaesarius (Wheeler, 1915), T. longaevus (Wheeler, 1915), T. hystriculus (Wheeler, 1915), and T. placivus (Wheeler, 1915) are transferred to the genus Eotemnothorax. The neotypes of E. gracilis, E. hystriculus, E. petiolatus, and E. placivus are designated, and queen of E. gracilis is described for the first time. The following 12 species are described as new to science: Eotemnothorax armatum sp. nov., E. balticus sp. nov., E. foveocephalus sp. nov. , E. groehni sp. nov. E. khomychi sp. nov. , E. odontos sp. nov. , E. pedunculatus sp. nov. , E. perkovskii sp. nov. E. punctatus sp. nov. , E. rav sp. nov. , E. rectispinus and E. rhytidus sp. nov. A key to identification of Eotemnothorax gen. nov. species is compiled. I suggested that Eotemnothorax gen. nov. can be a putative ancestor of the genus Temnothorax + Leptothorax genus group. It is assumed that Eotemnothorax gen. nov. species were arboreal rather than epigean.

Five Empitrombium species have been described from the Nearctic, Neotropical and Palaearctic Realms. The recent discovery of Empitrombium in Poland and France is the first record of the genus for the European part of the Palaearctic. The observations of Empitrombium paludosum sp. nov. at one locality in south-western Poland carried out for three consecutive years, vote for the presence of an established population and, at the same time, translate into widening the distribution of Empitrombium in the northern hemisphere, crossing the limit of 50 degrees north latitude. A second direct correlation of larvae and postlarval forms through laboratory rearing has been proceeded for genus members. Detailed insight into the morphology of active life instars revealed that the traits of active postlarval forms of Empitrombium overlap with the traits known for some genera of Microtrombidiidae, while the larvae bear an unusual combination of morphological characters, hitherto considered typical for higher and for lower microtrombidiids. The DNA sequences of the mitochondrial gene (cytochrome c oxidase subunit I), here provided for the first time for the genus members, further confirmed a separate generic status of Empitrombium.

This is the tenth paper in a series devoted to the studies on the genus Habroloma Thomson from China. Twenty new species from the subgenus Parahabroloma are described and illustrated: Habroloma (P.) arcuatipenne, sp. nov., H. (P.) breviacutum sp. nov., H. (P.) commune sp. nov., H. (P.) contracticollum sp. nov., H. (P.) jiecaikeng sp. nov., H. (P.) pulchripilum sp. nov., H. (P.) quadratipenne sp. nov., H. (P.) rectipenne sp. nov., H. (P.) rubidorsum sp. nov., H. (P.) shaxian sp. nov., H. (P.) subcompactum sp. nov., H. (P.) subflavoclavum sp. nov., H. (P.) subobscureollum sp. nov., H. (P.) subpraxilla sp. nov., H. (P.) subsemiparallelum sp. nov., H. (P.) tianshui sp. nov., H. (P.) wangorum sp. nov., H. (P.) xiaowudangense sp. nov., H. (P.) yangduanpai sp. nov. and H. (P.) yaosheng sp. nov.