In 2023, the outstanding Polish acarologist, Prof. Jerzy Wiśniewski, died. During 64 years of scientific work, he published 440 papers and several hundred descriptions of new mite species for science. In order to commemorate his achievements, a special issue of the Annales Zoologici was dedicated to him.

The present study continue our acarological investigations of Mesostigmatid mites inhabiting in ant nest's from Iran. I describe a new species of Cheiroseius Berlese, Cheiroseius wisniewskii sp. nov. based on morphological characters of the adult female specimens collected in association with Lasius neglectus Van Loon, Boomsma & Andrasfalvy, 1990 (Hym., Formicidae) in Gharaghoosh village, Saman county, Chaharmahal va Bakhtiari Province, Iran.

The adult stages of Multidendrolaelaps bialowiezae (Hirschmann et Wiśniewski) comb. nov. are described for the first time on the basis of specimens from Slovakia. The species was originally known from phoretic deutonymphs found on a cerambycid beetle in Poland and was placed in the subgenus Insectolaelaps Shcherbak. The female of M. bialowiezae is characterized by a modified laelapid type of sperm access system associated with the coxae III, which is specific to the digamasellid genus Multidendrolaelaps Hirschmann, and therefore the species is newly transferred to this genus. Some interspecific morphological characters that could be used to distinguish the deutonymphs of the (sub)genera Multidendrolaelaps and Insectolaelaps are discussed.

A redescription of Cosmolaelaps hastiger Berlese was conducted using its female and heteromorphic male type specimens. Five species, namely C. rectangularis Sheals, C. paravacua Nasr & Nawar, C. liae Bai & Gu, C. michaeli Huhta & Karg and C. pampaensis Duarte et al., have been identified as junior synonyms of C. hastiger. Additionally, Cosmolaelaps pinnatus Ramroodi et al. and C. angustiscutatus Willmann have been identified as junior synonyms of C. ornatus Berlese and C. gryllotalpae Berlese, respectively. The status of other species within the Cosmolaelaps genus has also been discussed. Based on our analysis, including consideration of synonymies and new combinations, the total number of species within the genus is now 126.

During an investigation on laelapid mites deposited in Ohio State University Acarology Laboratory (OSAL) a description of a new species of Cosmolaelaps Berlese, C. wisniewskii sp. nov., is done based on morphological characters of female and male specimens which were collected from soil and leaf litters from the United States of America. Some other species of this genus have been determined based on the specimens which deposited in OSAL.

Phytoseiid mites (Parasitiformes: Phytoseiidae) are well known as a group of predatory forms, including these of them which successfully using to control phytophagous mites and other small pests. Despite of noticeable increase in the number of researchers deal with of phytoseiids in recent years, there are of large number of species of this family, the level of knowledge about which is extremely small. First of all, this applies to rare species, known today only from isolated finds. At the same time, there are of large number of species of this family, the level of knowledge about which is extremely small. Such species include Amblyseiella (Litoseia) spectata (Kolodochka). Therefore the first record of this rare species in Poland has expanded the known boundaries of its distribution. And the simultaneous discovery of a previously unknown male added the information about the characteristics of the ecology and morphology of this species.

A new species, Anchigamasus cansigliensis sp. nov. collected in Veneto, North-Eastern Italy, is described. Additionally, Anchigamasus geileri (Karg, 1968) is designated as a type species for Anchigamasus genus instead of A. crassicornutus (Willmann, 1954).

Light microscopy and scanning electron microscopy were used to study and describe the larval stage of Evimirus uropodinus (Berlese, 1903) for the first time. It is also the first description of larvae at the genus level and the first report of E. uropodinus from Greece. In general, the larval morphology of Eviphididae Berlese is poorly known. We discussed the morphology of E. uropodinus larvae with data on all larval stages described so far in Eviphididae, i.e. Alliphis necrophilus (Christie, 1983), A. siculus (Oudemans, 1905), Eviphis cultratellus (Berlese, 1910), Pseudoalliphis sculpturatus (Karg, 1963), Thinoseius spinosus (Willmann, 1939) and Uroiphis greeni (Evans, 1980). The E. uropodinus larvae possess the characteristic posterodorsal sculptured pattern, a feature that was found so far only in larvae of E. cultratellus, and possess the simpliest cheliceral dentition of all known larvae of Eviphididae. The larval chelicera of E. uropodinus has no pilus dentilis and possesses specialized sensillae on the tip of a fixed digit, a set of characters that E. uropodinus larvae share with E. cultratellus and U. greeni. We found a 3-tined apotele in the described larva and discussed its presence in E. uropodinus.

In the present paper, we continue our studies on quill mites of the family Syringophilidae parasitising birds of the family Sturnidae. Herein, we describe a new species, Picobia wisniewskii sp. nov., collected from the red-winged starling Onychognathus morio (Linnaeus) in Tanzania. Additionally, we provide an emended diagnosis and new host records for Picobia lamprotornis Klimovicova et al., 2014 and Picobia sturni Skoracki et al., 2004.

The biodiversity of parasitic skin mites, including the Demodecidae of soricomorph mammals, is very poorly known. So far only seven species from this family have been described, associated with four host species: two each from the common shrew Sorex araneus, the lesser white-toothed shrew Crocidura suaveolens and the Mediterranean water shrew Neomys anomalus (Soricomorpha: Soricidae), and one from the European mole Talpa europaea (Soricomorpha: Talpidae), known from single or few records, only from Europe. However, another species from the European mole has presently been described, Demodex labialis sp. nov.; this species is characterized by strict topographic specificity, inhabiting only the lip area. The demodecid mites of the mole have low infection potential, due to the host's lifestyle limiting the possibility of parasite transmission, and its restricted location. As such it appears rare: it has been found in only 9.7% (95% confidence interval 2.7–25.5) of 31 examined moles, with a mean intensity of 10.7. However, this mite probably occurs in moles throughout its range.

Twelve species of ptyctimous oribatid mites in total are reported from newly examined 34 samples collected from Uganda in Kibale National Park and its direct neighbourhood. In this number seven species are new to fauna of Uganda and one (Plonaphacarus quasibrevisetus Niedbała sp. nov.) new to science is described and illustrated. Another species Steganacarus (Steganacarus) carusoi Bernini et Avanzati, 1989 reported in subsaharan Africa for the first time is also illustrated and supplied with diagnosis based on Ugandan specimen. Summary of Uganda ptyctimous fauna indicates that superfamily Phthiracaroidea predominates numerically over Euphthiracaroidea (19 vs. 7 species).

The morphological ontogeny of Nothrus palustris C.L. Koch, 1839 is redescribed and illustrated. The morphology of this species has already been investigated in the last century, but these descriptions were either general or incomplete, and lack some cupules, lateral aspect of some instars, and leg setation, which are necessary for morphological comparisons. In the larva of N. palustris the bothridium is weakly developed and bothridial seta is short, whereas in the nymphs and adult the bothridium is well-developed, and bothridial seta is setiform and very long. In this species one pair of exobothridial setae is present. In all instars most prodorsal setae are short, with thickened ro and le in the larva, and ro, le, and in in the nymphs and adult. Most gastronotal setae are of medium size or short, except for long f₁ and very long h₁ in the larva, and long h₁ and very long h₂ in the nymphs and adult. All setae are finely barbed in the larva, and smooth in the nymphs and adult, and they are usually covered with phylliform cerotegument. In all instars the femora are with reticulate ornamentation, and some leg setae (d, l, ft) are thickened and finely barbed, whereas the other setae are thin and smooth. Formulae of femoral setae (leg I–IV) are 7-7-4-3 in the deutonymph, 8-8-6-5 in the tritonymph, and 8/9-8-6-5 in the adult. The illustrations of N. palustris are supported by SEM images. We also summarised knowledge on the ecology and compared the molecular data (COI) of N. palustris from different locations, based on our own and public data.

During the study on eriophyoid mite fauna (Acari: Eriophyoidea) of Phlomis plants (Lamiaceae) in northwest Iran, two species were collected: Aceria wisniewskii Lotfollahi et Houshyari sp. nov. on Phlomis sp. in Naghadeh county of West Azerbaijan province and Aceria onychia (Nalepa, 1915) on Phlomis herba-venti L. in Meshginshahr county of Ardabil province.

During field surveys of eriophyoid mites in northeast Iran (Razavi Khorasan, Iran, summer 2023), two new vagrant eriophyid species (Acari: Eriophyoidea: Eriophyidae) on Asteraceae plant species were discovered, illustrated and described. They are Aceria dorbadamiensis sp. nov. on Tripleurospermum disciforme (C.A.Mey.) Sch.Bip. and Aculus quchaniensis sp. nov. on Aster altaicus var. canescens (Nees) Serg. We reported an eriophyoid mite on plant genus Tripleurospermum for the first time. No apparent symptoms were observed on both host species.

In this paper we show the unexpected fate of the odd Formica polyctena ‘colony’, spontaneously created at the bottom of a concrete post-nuclear bunker by workers falling into it en masse – with no way to leave – from their maternal nest located at the outlet of the bunker ventilation pipe (see Czechowski et al. 2016, Rutkowski et al. 2019). At the end of previous research, we inserted a wooden structure into the pipe to allow the ants trapped below to return to their maternal colony, which they did. Then it turned out that the ants, now able to move freely to and from the bunker, began to use the lower nest (in the form of an earthen mound) as an auxiliary nest for the colony, mainly as a winter nest (during the research period they inhabited it for two consecutive winters), and the bunker itself as a place for storing corpses and waste. We discussed these findings in the context of seasonal changes in temperature and relative humidity measured for the interior of the lower and upper nest mound and the air inside and outside the bunker. Our results highlight the extreme nesting flexibility shown by this species under very unusual environmental circumstances.

The European stag beetle Lucanus cervus cervus is the largest European member of the Lucanidae and is characterised by the extremely enlarged mandibles of the male. Some aspects of the morphology of this species have been extremely well studied, while others have been largely neglected. In the present paper we fill some of these gaps by focusing on 3D measurements based on a µ-CT scan. We show that the largest part of the body is filled by a massive tracheal system (48.8%), followed by the exoskeleton (21.1%). The massive tracheal system covers large parts of the internal anatomy, leaving limited space for other systems such as the nervous system (0.2%) or the digestive system (0.7%), which are very small and delicate compared to other species. We suggest that no significant relative increase in the volume of the tracheal system is possible in a flying insect without potentially rendering another organ system inoperable. The cuticle of L. cercus cercus is extremely thick compared to other species, which is most likely due to the fact that the males have extremely enlarged mandibles, which are also used in male-male fights. They can generate strong forces that also result in massive stresses that need to be dissipated by the thick cuticle. We can also show that there are significant differences between 2D and 3D measures of specific distances in highly 3-dimensional structures such as the length of the mandibles. We therefore suggest that such 3D measures be included in future analyses. In summary, we hope to further promote the importance and significance of 3D morphometric measures and suggest that at least the volumes of the studied materials should be included in future CT-based studies of insects.