Trithemis annulata (Palisot de Beauvois, 1807) is a widespread Afrotropical species that substantially expanded its range in Mediterranean Europe in the second part of 20th century and very recently in the West Balkan region. A field study was carried out from June to September 2024 in the southern parts of Bosnia and Herzegovina and the Neretva River delta in Croatia in order to investigate the species’ presence in this area. During the survey, T. annulata was found at 14 locations, seven in each country. The observations from Bosnia and Herzegovina represent the first record of this species for the country. It was found in a wide variety of habitats, both lentic and lotic, including lakes, reservoirs, rivers, larger ponds and canals. Considering that, at several of these locations, the species was not found during surveys in 2022 and 2023, it most likely spread to this area recently. Additionally, two observations of T. annulata from North Macedonia that were found in the online databases Observation and iNaturalist represent the first documented reports for this country. These findings constitute a substantial increase in species range and abundance in the region. The species’ distribution andspread in the Balkan Peninsula is also outlined and discussed.

The El Kala wetland complex, located in the far northeast of Algeria, provides ideal ecological conditions for wintering migratory waterbirds. Among these sites, the Mekhada marsh, designated a Ramsar site in 2004, stands out as one of the most biologically diverse wetlands in the region. It supports several emblematic waterbird species, including the Red-crested Pochard ( Netta rufina ), which is the focus of this study. This species is rarely observed in Algerian wetlands and typically occurs in very small numbers. In June 2025, an exceptional observation was made of a female Red-crested Pochard accompanied by her ducklings at the Mekhada marsh. To our knowledge, this represents the first documented breeding record of Netta rufina in the El Kala wetland complex.

This is the first annotated checklist of the Hydraenidae of Croatia. It is based on reliable literature data and the examination of unpublished specimens identified by the authors. A total of 65 species is confirmed to occur in Croatia: 26 species of Hydraena Kugelann, 1794, nine species of Limnebius Leach, 1825, and 30 species of Ochthebius Leach, 1815. With regard to the biogeographical regions of Croatia, 47 of these species are found in the Mediterranean Region, 28 in the Continental and 14 in the Alpine Region. Four species are recorded from Croatia for the first time: Hydraena (s. str.) assimilis Rey, 1885, Limnebius (s. str.) aluta Bedel, 1881, Ochthebius ( Asiobates ) flavipes Dalla Torre, 1877, and O. (s. str.) pedicularius Kuwert, 1887. Four species are classified as “unconfirmed or doubtfully recorded” from Croatia. Ochthebius ( Asiobates ) bicolon Germar, 1824 is deleted from the Croatian checklist. An additional 29 species that potentially could occur in this country are discussed. Only one hydraenid species, Hydraena angustata Sturm, 1938, is currently regarded as endemic to Croatia, but it is assumed to be more wide-spread. A total of 14 Croatian hydraenid species is regarded as endemic or subendemic to the Balkan Region. Lectotypes are designated for Hydraena (s. str.) croatica Kuwert, 1888 and Ochthebius ( Aulacochthebius ) narentinus Reitter, 1885. A photograph of the dorsal habitus of H . (s. str.) croatica is published for the first time. The history of the exploration of the Hydraenidae of Croatia is outlined. Compared to other South European countries like Spain or Italy, the knowledge of the hydraenid fauna of Croatia is still remarkably poor, and very few Croatian hydraenid specimens have been barcoded so far; only one specimen was found databased in BOLD and GeneBank (accessed June 2025).

The silver-striped hawk-moth ( Hippotion celerio ) is a quite rare species of the Croatian fauna, having only five past records from the 19th and 20th century. Given the lack of recent records, the species' presence in the country was deemed questionable. Here presented and discussed are three new records of this species from coastal Croatia which give us new distribution data while simutaneously confirming its occasional presence in the country.

The presence of the thecline lycaenid butterfly Atara arata (Bremer, 1881) is recorded from the region of Isparta in west-central Türkiye for the first time, representing a new country record of both genus and species some 7,500km west of its previously known westerly limits in eastern China. Several specimens were seen in a remote montane locality on several visits in the late spring and early summer of 2024, indicating a small resident colony. One worn male specimen was collected and dissected to confirm identity. Distribution, variation and habitat is briefly discussed. A lectotype is designated for Thecla tyrianthina Butler, 1881 (=Atara arata Bremer).

This paper presents the results of a phytosociological study of the two southeasternmost islets in Croatia, Veliki Školj (0.16 km²) and Supetrić (0.88 ha), near the village and port of Molunat (Dubrovnik region). Drawing on 20 phytosociological relevés collected in 2023 and 2024 using the Braun-Blanquet approach, the study identified four plant associations (Myrto communis-Pistacietum lentisci, Myrto communis-Quercetum ilicis, Limonietum anfracti, and Posidonietum oceanicae), one subassociation (Centaureetum ragusinae limonietosum anfracti), and three communities (Euphorbia dendroides-Quercus ilex, Dactylis glomerata subsp. hispanica, and Cynodon dactylon), spanning six vegetation classes. The stands of the Myrto-Quercetum ilicis association covers more than 95% of Veliki Školj’s area. Importantly, the islet is at the southeasternmost line of the distribution range of Centaurea ragusina. Intensive goat grazing has significantly impacted the floristic diversity of both the maquis and grassland ecosystems.

Tortricid moths, or leafroller moths, are one of the most economically important insect families worldwide. Many tortricids are significant pest species in agriculture and forestry, yet no checklist for Croatia exists that would allow better monitoring and managing of the existing pest species. In total, more than 300 literature sources were reviewed to compile the first species list of tortricid moths for Croatia. The list includes material collected during field surveys conducted by the authors in Croatia, as well as specimens held in the Koča Microlepidoptera collection and Igalffy Microlepidoptera collection of the Croatian Natural History Museum in Zagreb. The list has 417 species of Tortricidae.Altogether 31 species are new to the Croatian fauna: three species that are held in museum collections and 28 species that were collected by the authors.For each species, an exhaustive review of literature references is provided, from the oldest historical records to the recent ones. Data from the field surveys and/or a reference to the collection where vouchers are preserved are also provided. The taxonomic categories included are subfamilies, tribes, genera, subgenera, and species. In addition, distributional information for each species is given according to its occurrence in the three biogeographical regions of Croatia (Alpine, Mediterranean, and Continental regions).

Barrage-lake systems are a rare natural phenomenon with specific ecological characteristics that are greatly affected by tufa formation. Our main goal was to investigate benthic macroinvertebrate communities and their longitudinal variations within the lakes arranged in cascades in the Dinaric karst hydrosystem. Each lake within the Plitvice Lakes system studied presented with a distinct community, showing the effects of the barrage-lake system on the macroinvertebrates in these lakes. We observed a downstream decrease in taxa richness, abundance and Shannon diversity index along the longitudinal profile of the studied barrage-lake system. This pattern is most probably a result of decreased organic matter and increased tufa deposition. Overall, our results suggest that the hydrosystem studied represents a sequence of sediment sinks in which lakes retain and accumulate organic matter and fauna. Therefore, each lake acts as a filtering screen and consequently appears to be a small ecosystem. Each lake has its own community characteristics, regardless of the fact that water flows from one lake to the next, connecting them and creating very similar abiotic conditions in each lake along the system.

Although Aspidogaster conchicola is a common and widespread parasite of freshwater molluscs, knowledge about its distribution and hosts in Croatia is still insufficient. The aim of our research was to investigate the presence of A. conchicola in the freshwater mussel Unio pictorum, which is widely distributed in the rivers of Europe. The study was conducted in the Mrežnica River, where U. pictorum is a common species. Five specimens of U. pictorum were collected by scuba diving in October 2021. The dissection of mussels was carried out in the laboratory, and all tissues were inspected under a stereo microscope. Determination of the parasite was performed based on the number and arrangement of alveoli. The results showed that the prevalence of infection was 40% (two out of five mussels were infected), and the intensity of infection was 2 to 3 specimens per mussel. All parasites were detected in the mussels’ pericardial cavity. In conclusion, this is the first record of A. conchicola in U. pictorum in Croatia.

Since Kosovo is the least explored territory in the Balkan Peninsula when it comes to the study of spider fauna, with large, untouched areas, we aim to explore it in detail. From Bjeshkët e Nemuna Mountains only 15 species have been reported. We collected and identified 323 spider specimens (88♂♂, 235♀♀) from April 2018 to August 2021 at 20 sites in Bjeshkët e Nemuna National Park between 529 and 2066 m a.s.l. These specimens belong to 91 species, 65 genera, and 23 families. Of these, 42 species, 13 genera, and 2 families are new records for the spider fauna of Kosovo, and 90 species are new for the mountains. As a result of our research, the list of species known from the studied region increased from 15 to 105 and the number of known spiders in Kosovo increased to 248 species.