The Old World swallowtail Papilio machaon Linnaeus, 1758 is one of the most well-known and most characteristic members of the family Papilionidae. Over the past two centuries, the butterfly has been the subject of many studies. P. machaon is characterised by a tendency to change the wing colour pattern. In turn, due to the great interest of collectors and amateur entomologists, these studies have been converted into the description of over 100 colour forms, aberrations and subspecies. In this study, mitochondrial DNA (mtDNA), 16S rDNA and cytochrome b sequences were used to examine the correlation between the intraspecific classification and genetic structure of P. machaon. The study used 87 specimens from 59 different localities covering the geographic distribution of this species in the Palaearctic. The phylogenetic relationships within and between the Old World swallowtail subspecies showed that the intraspecific classification proposed by various authors does not correlate with the variability in mitochondrial DNA sequences. In addition, populations occurring at the species distribution borders in the Palaearctic Region (i.e., Japan, Kamchatka, Morocco and Sakhalin) are genetically distinct from other species.

The paper gives the results of the first studies on the molecular divergence between native and non-native populations of Speonomus normandi hydrophilus (Jeannel, 1907). This species is endemic to Massif Arize in the Central Pyrenees (France), and represents highly specialised organisms that live underground. In 1982, one hundred specimens of S. normandi hydrophilus had been experimentally introduced into the Dzwonnica Cave (Poland). Since then, a numerous population has developed in the Towarna-Dzwonnica cave system, and the neighbouring Cabanowa Cave. After almost 40 years of isolation between native and non-native populations, the genetic variations were examined using the COI and 28S rDNA genes. Analyses of the haplotypes of 28S showed one common haplogroup, which confirms the origin of the Polish group. The differentiation of haplotypes for the COI marker was high for both the French and Polish populations. Altogether 18 haplotypes of this marker have been detected, 12 in the French population and 9 in the Polish. However, only a portion of the haplotypes is shared between the native and introduced population.

The year 2018 is particularly important in the history of zoological research in Poland. A hundred years ago, Kazimierz Demel published the first work concerning the terrestrial cave fauna of caves in the Ojców area. In this paper we present the extent of research on the terrestrial invertebrate fauna of Polish caves in the last 100 years. All accessible research papers that have been published during this period were analysed. Based on published literature, 593 species of terrestrial invertebrate were recorded in Polish caves. Additionally, detailed list of species of individual taxonomic groups was provided.

The SSU nuclear rDNA (encoding 18S ribosomal RNA) is one of the most frequently sequenced genes in the molecular analysis of insects. Molecular apomorphies in the secondary and tertiary structures of several 18S rRNA length-variable regions (LVRs) located within the V2, V4, and V7 hypervariable regions can be good indicators for recovering monophyletic groups within some heteropteran families. Among the LVRs that have been analysed, the LVR L in the V4 hypervariable region is the longest and most crucial for such assessments. We analysed the 18S rRNA V4 hypervariable region sequences of 45 species from the family Cydnidae, including all 6 subfamilies (Amaurocorinae, Amnestinae, Cephalocteinae, Cydninae, Garsauriinae, and Sehirinae) and three pentatomoid families (Parastrachiidae, Thaumastellidae, and Thyreocoridae), which have often been included in the broadly defined Cydnidae family. This is the first time that representatives of all Cydnidae subfamilies have been included in a molecular analysis. Only taxa from two subfamilies, Sehirinae and Cydninae, have been used in previous molecular studies. The secondary and tertiary structures of the LVR L were predicted for each species using the two-step procedure already accepted for such analyses to recover any molecular apomorphy essential for determining monophyly. The results of our comparative studies contradict the current understanding of the relationships among burrowing bugs and the current family classification.

Coxal combs, found only in members of the ‘cydnoid’ complex (comprising four families: Cydnidae, Parastrachiidae, Thaumastellidae, and Thyreocoridae) within the superfamily Pentatomoidea, have long been regarded as a character confirming their close evolutionary relationship. However, many studies have demonstrated that these four families are phylogenetically distant. Others have been treated as subfamilies of the broadly defined Cydnidae, with the coxal combs as the only character linking them. This is the first study on the origin of coxal combs in species of all families and subfamilies that represent the broadly conceived Cydnidae (69 species in 39 genera). Moreover, this study presents the first 16S rDNA gene sequences providing a basis for such analyses. The analyses included DNA sequences of 62 species in 34 genera of Cydnidae sensu stricto, three species in two genera of Thyreocoridae, two species in two genera of Parastrachiidae, and two species in one genus of Thaumastellidae. The sequence analysis in the family Cydnidae covered 35 species representing 19 genera of the subfamily Cydninae, 16 species in eight genera of the subfamily Sehirinae, five species in two genera of Amnestinae, three species in three genera of Garsauriinae, two species in one genus of Cephalocteinae, and one species of Amaurocorinae. The results of our study demonstrate the independent origin of coxal combs in taxa of the ‘cydnoid’ complex within the superfamily Pentatomoidea. They confirm the polyphyly not only of the entire ‘cydnoid’ complex but also of the family Cydnidae itself.

Urania sloanus is an endemic species in Jamaica. The species probably became extinct at the end of the 19th century or the beginning of the 20th century. During the work on combining the collections of exotic butterflies in the Upper Silesian Museum in Bytom, one specimen of this taxon was found. The discovery of this species in the Museum of Upper Silesia in Bytom led us to search for entomological collections in other Polish museums. As a result of our search, we found three additional specimens: two specimens in the collection of the Museum of Natural History of the University of Wrocław and one at the Zoological Museum of the Polish Academy of Sciences in Warsaw. In total, in the Polish museum collections, the species was represented by four specimens. In our publication, we also paid attention to the role of museum collections as important repositories of biodiversity in the context of the development of modern methods in the field of molecular genetics, as an important source of genetic information.