Entomologica Austriaca 33

Invasive alien species are increasing globally in numbers posing threats to biodiversity, the economy, and human health. Europe has documented, besides North America, the highest numbers of invasive species, with expenses caused by invasive species reaching up to millions of Euros. The Asian hornet – Vespa velutina (subspecies: nigrithorax du Buysson, 1905) – was the first Vespidae species on the list of invasive species of European concern. The Asian hornet was first recorded in 2004 in southern France and expanded its range actively by its flight ability and passively via human transportation across Europe. In 2024, a single female individual was detected in Austria putting beekeepers and scientists on alert. We screened scientific literature on V. velutina in Europe and provide an overview of its potential impacts on the economics of beekeepers, regional biodiversity, and human health. Although numerous works have been published about its potential threats, we found data gaps and limitations in the suitability of several study designs to quantitatively verify its impact. We highlight the necessity to further monitor the expansion of V. velutina, investigate open research questions, and inform the public about invasive alien species.

Some organs in evolutionary history appear to have emerged without clear precursors and transitional forms, challenging the gradualist assumptions central to Darwinian theory. Strikingly, studies focusing on such evolutionary novelties remain limited to a few well-characterized cases. This review examines two instructive examples in insects that illustrate distinct pathways to fundamental phenotypic innovation. The first concerns the origin of insect wings, undoubtedly one of the most significant and extensively studied morphological novelties in arthropods. Since the early post-Darwinian era, two competing explanatory models have dominated the debate: the paranotal lobe hypothesis and the leg-exite hypothesis. Recent evo-devo research has reshaped this discourse, culminating in the integrative dual origin hypothesis. However, emerging evidence has reignited the controversy, suggesting that wing evolution may be more complex than previously thought. The second example focuses on wing-associated circulatory organs, evolutionary novelties that have received comparatively little attention. These small pumping units drive hemolymph flow through the wing vein network, a mechanism essential for maintaining sensory structures on the wings and preserving cuticular hydration, which is critical for their biomechanical performance. While the ancestral condition is represented by modifications of the dorsal vessel, fully independent wing hearts have evolved multiple times across various insect lineages as novel pulsatile organs. Their emergence appears to be a consequence of spatial constraints imposed by the progressive evolution of the insect flight apparatus. Research in Drosophila revealed that these organs originate from four pericardial precursor cells and represent evolutionary novelties in the strictest sense, as they not only lack homology with any known ancestral structure but also develop as discrete modules under the control of unique gene regulatory networks. Wing hearts thus represent a versatile and experimentally accessible model system for studying the emergence and integration of novel traits — a central, yet still underexplored theme in evolutionary biology.

The first record of the vagrant emperor (Anax ephippiger) from Styria was obtained on 20 April 2025 in Pirka near Graz. This brings the total number of dragonfly species known to occur in Styria to 65, with up to five further new records expected in the near future.

The morphology of the proboscis tip and its sensilla were studied in relation to feeding preferences in 165 species of Papilionoidea representing all families and subfamilies. The shape of the drinking region with which fluid is taken up, and the contact chemo-mechanosensilla, socalled sensilla stylococonica, were compared using light microscopy and exemplarily examined with scanning electron microscopy. Despite the same composition of the sensilla styloconica in all butterflies studied here, their number and arrangement as well as their length and micromorphology may vary greatly. While the morphology of the proboscis tip and the sensilla styloconica are the same in all Hesperiidae, the studied Papilionidae, Hedylidae, and Pieridae show certain differences within families. In contrast, the diversity of the drinking region as well as the shape, length, number, and arrangement of sensilla styloconica is very large within the studied Nymphalidae, Lycaenidae, and Riodinidae. Most primarily non-nectar feeding species show numerous sensilla styloconica forming a characteristic brush-shaped drinking region. A new type of proboscis was found in tropical honeydew feeding Lycaenidae that lack sensilla styloconica on their short proboscis possessing long bristle-shaped sensilla. Likewise, the sensilla styloconica are missing in a few nectar feeding Pieridae and Riodinidae. The plesiomorphic type of sensilla styloconica of Papilionoidea features several longitudinal cuticle ribs. Independent evolutionary pathways led to apomorphic traits of the sensillum stylus and the remarkable diversity of the sensory equipment of the Papilionoidea.