Existing techniques for examining the everted vesica (endophallus) of Lepidoptera are based primarily on cuticular preparations macerated with a caustic solution for taxonomic study. These techniques destroy muscles and other soft tissue, thus studies of the functional anatomy of the skeletomuscular apparatus of the phallus are not possible. Injection of formaldehyde solution into the phallus of fresh specimens is proposed as a new approach for studying the intact anatomy of this structure. The new technique results in simultaneously everting and fixing the vesica, resulting in a better approximation of its functional shape. This method produces properly fixed tissues and the whole structure can be processed for various further studies, including histology sectioning, scanning electron microscopy, and confocal laser scanning microscopy. The commonly used stubs for scanning electron microscopes do not allow observation of the sample from all aspects. This problem was solved by the modification of a commercially available stub. The device allows 360° rotation of the phallus, and the concept can be applied for observation of other objects as well.

Pollen analysis of crop samples was used to identify the food sources of species of beetles of the family Oedemeridae in Bulgaria. A total of 21 species and subspecies were examined; pollen was present in the crops of 18 of the species. Our study is the first to provide information on the food sources of four species and subspecies: Chrysanthia varipes varipes, Anogcodes seladonius turcicus, A. ruficollis and Oedemera flavicans. New data on food sources for many of the other species studied was obtained and feeding on pollen of gymnosperms and honeydew by some of the species was confirmed. Possible mechanisms for digesting pollen are discussed. There was no evidence of either the pollen germinating or being predigested in the crop of the beetles.

During the period 1969-2019, longhorn beetles (Coleoptera: Cerambycidae) were studied in Bulgaria. In different regions of the country, 144 cerambycid taxa from six subfamilies were established: Prioninae (five species), Lepturinae (37 species and subspecies), Necydalinae (one species), Spondylidinae (nine species and subspecies), Cerambycinae (46 species and subspecies) and Lamiinae (46 species and subspecies). New localities of 14 rare cerambycid taxa were established (Pedostrangalia revestita, Alocerus moesiacus, Anisarthron barbipes, Icosium tomentosum atticum, Paraclytus sexguttatus, Aegomorphus krueperi, Agapanthia frivaldszkyi, Deroplia genei genei, Dorcadion equestre transsilvanicum, Phytoecia albovittigera, Phytoecia praetextata praetextata, Pogonocherus hispidus, Niphona picticornis and Saperda perforata). New longhorn beetles were also found in the West Balkan Range, the Eastern and Western Rhodopes, Maleshevska Planina Mt. and North-eastern Bulgaria. These new records enlarged the knowledge about the regional distribution of longhorn beetles in Bulgaria.

The saproxylic species Pediacus dermestoides (Fabricius, 1792) is reported from forest habitats located in five mountains in Bulgaria. The adult beetles were found under the bark of several host tree species or captured with flight interception traps. It seems that P. dermestoides might be widespread in the mountain forests in Bulgaria.

The invasive alien species Cynaeus angustus (LeConte, 1851) was detected for the first time in Bulgaria. In 2020-2022, eight exemplars of this North American pest were collected at three sites along the Danube River. Its distribution, microhabitat affinity, food preferences as well as some methods for control are outlined. Photographs of the adult habitus, male genitalia and female ovipositor are also provided.