Abstract Background We have developed a new platform named "Biologer" intended for recording species observations in the field (but also from literature resources and collections). The platform is created as user-friendly, open source, multilingual software that is compatible with Darwin Core standard and accompanied by a simple Android application. It is made from the user’s perspective, allowing everyone to choose how they share the data. Project team members are delegated by involved organisations. The team is responsible for development of the platform, while local Biologer communities are engaged in data collection and verification. New information Biologer has been online and available for use in Serbia since 2018 and was soon adopted in Croatia and Bosnia and Herzegovina. In total, we have assembled 536 users, who have collected 163,843 species observation records data from the field and digitalised 33,458 literature records. The number of active users and their records is growing daily. Out of the total number of gathered data, 89% has been made open access by the users, 10% is accessible on the scale of 10×10 km and only 1% is closed. In the future, we plan to provide a taxonomic data portal that could be used by local and national initiatives in Eastern Europe, aggregate all data into a single web location, create detailed data overview and enable fluent communication between users.

Aerogels are the least dense and most porous materials known to man, with potential applications from lightweight superinsulators to smart energy materials. To date their use has been seriously hampered by their synthesis methods, which are laborious and expensive. Taking inspiration from the life cycle of the damselfly, a novel ambient pressure‐drying approach is demonstrated in which instead of employing low‐surface‐tension organic solvents to prevent pore collapse during drying, sodium bicarbonate solution is used to generate pore‐supporting carbon dioxide in situ, significantly reducing energy, time, and cost in aerogel production. The generic applicability of this readily scalable new approach is demonstrated through the production of granules, monoliths, and layered solids with a number of precursor materials.

Leptoglossus occidentalis Heidemann, 1910 is an invasive bug species native to the western part of North America and one of 16 alien Heteroptera species in Europe. After it was first found in Italy in 1999, the species spread fast across the continent, including the Balkan Peninsula. Our study confirms the species presence in Bosnia and Herzegovina and gives data on its distribution, including the earliest records for the country. Up untill now the species is found at nine different locations in the period from 2008 to 2016. The record from early spring 2008 suggests that the species was already present in Bosnia and Herzegovina in 2007 or even earlier. Most records pertain to overwintering adults. For the first time the species is reported from Bosnian pine (Pinus heldreichii H. Christ). The species is also reported from Klek village in Dubrovnik region, south Croatia.

The results of the first study of the dragonfly fauna in northwest Bosnia are presented. Field surveys were conducted in summer 2012 and 2013, resulting in the identification of 36 species. Out of these, 34 are new for the region. The present paper gives a detailed overview of the results and a comparison of the dragonfly fauna composition of the region studied with the neighboring areas within Bosnia and Herzegovina and Croatia is made. The most abundant species were: Calopteryx virgo (Linnaeus, 1758), Sympetrum sanguineum (Müller, 1764), Onychogomphus forcipatus (Linnaeus,1758), Somatochlora meridionalis Nielsen, 1935, Calopteryx splendens (Harris, 1782) and Platycnemis pennipes (Pallas, 1771). Noteworthy are the records of Chalcolestes viridis (Vander Linden, 1825) and Coenagrion scitulum (Rambur, 1842), two species that are rare in Bosnia and Herzegovina, and also Coenagrion ornatum (Selys, 1850) and Cordulegaster heros Theischinger, 1979, species of European conservation concern. Distribution and the status of these species and the conservation of dragonfly species in the country are briefly discussed. The data collected represent an important contribution to the knowledge of the dragonfly fauna of the Una River basin and Bosnia and Herzegovina.

Records of the biting midge Forcipomyia paludis (Macfie, 1936) from Slovenia and Bosnia and Herzegovina are reported herewith as the first finds of F. paludis in both countries, together with new records from Croatia and Sweden. This biting midge is a temporary ectoparasite of dragonfly imagines and the only ceratopogonid species known in Europe to feed specifically on this insect group. Forcipomyia paludis is already known in 18 European countries. Prior to this report, F. paludis was known to infest 67 dragonfly species in Europe. Thirteen dragonfly imagines from 11 sites in Slovenia, 27 imagines from 13 sites in Bosnia and Herzegovina and six imagines from two sites in Croatia having F. paludis on their wings were recorded. Additional data for 50 imagines from 15 sites in Sweden are also presented. In Slovenia, the species is known to occur in the Gorenjska, Goriška Brda, Vipava River Valley, Coastal-Karst region, Central Slovenia, Kočevska region and Bela krajina, while in Bosnia and Herzegovina it is known only from south Herzegovina (Ljubuški, Čapljina, Mostar and Stolac areas). In Croatia, the species is present in several parts of the country, while in Sweden it occurs only in the southern and middle parts of the country (Skåne, Öland, Gotland, Göteborg and Gävle). Six new dragonfly host species and the northernmost occurrence of F. paludis are also reported.

Three butterfly species were recorded for the first time for the fauna of Bosnia and Herzegovina in the Herzegovina region: Danaus chrysippus, Cacyreus marshalli and Carcharodus orientalis. The records represent expansions to the known distribution, although the presence of all three species was expected as they are to be found in neighbouring countries. This is the third record that D. chrysippus has reached southern Croatia, and the first time it has been observed in Bosnia and Herzegovina. The record of the non-native C. marshalli fills the distributional gap, and the record of C. orientalis, a rare and local species in the region, represents an increase of the known distribution in the mainland of the western Adriatic coastline. In the future, additional records of rare and unrecorded species are expected in the country.

Ceratomegilla ( Adaliopsis ) alpina (Villa & Villa, 1835) is a Pleistocene glacial relict with disjunctive distribution in high mountain areas of the Alps, Carpathians and the Bulgarian mountains, where it inhabits mountain meadows from 800 to 2.000 m a.s.l. (Fürsch 1967, Haviar 2003, Kovar 2007). Two ssp. are recognized, Ceratomegilla alpina alpina Villa & Villa, 1835, restricted to the Alps (Austria, France, Italy, Liechtenstein and Switzerland), and Ceratomegilla alpina redtenbacheri Capra, 1928 with a wider distribution, including Austria, Bulgaria, Germany, Poland, Romania, Slovakia and Ukraina (Kovar 2007, Canepari 2013). In comparison with C. a. alpina , C. a. redtenbacheri is characterized by smaller humeral red spot reaching half of elytra width and without sub-humeral black spot; posterior spot roundish or square (never stripe shaped); body more convex and less pointed posteriorly (Capra 1928). Travnik C. a. Sampling site “Travnik