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Bee lice (Braulidae) are small parasitic flies, which are adapted to live on their bee host. As such, the wingless Braula coeca is a parasite of the common honey bee Apis mellifera and it is well adapted to attach to its hairy surface. The attachment system of B. coeca provides a secure grip on the fine setae of the bee. This is crucial for the parasite survival, as detachment from the host is fatal for the bee louse. The feet morphology of B. coeca is well adapted to the challenging bee surface, notably by strongly broadened claws, which are split into a high number of comb‐like teeth, perfectly matching the diameter of the bee hairs. Based on microscopy observations, both the morphology and material composition of the tarsi of B. coeca are characterized in detail. Using high‐speed video analysis, we combine the morphology data on the attachment system with a behavioural context. Furthermore, we directly measured the attachment forces generated by the bee lice in contact with the host. In particular, the claws are involved in attachment to the host, as the interstices between the teeth‐like spines allow for the collection of several hairs and generate strong friction, when the hairs slip to the narrow gap between the spines. The overall morphology of the tarsus produces strong attachment, with average safety factors (force per body weight) around 1130, and stabilizes the tarsal chain with lateral stoppers against overflexion, but also allows for the fast detachment by the tarsal chain torsion.

In Odonata, a direct flight mechanism with specialized tendons evolved. One particular adaptation, the implementation of the rubber-like protein resilin in these cap tendons, might be of major importance. Although resilin was first described in one tendon of Odonata, to our knowledge no comprehensive study about the presence of resilin in the thorax exists yet. We investigated various species of Odonata, using mCT, dissection and fluorescence microscopy. Here we show a complete mapping of the odonatan pterothorax, regarding the presence of tendons and their properties. Thus, 20-21 cap tendons in the pterothorax of Odonata show the presence of resilin. While performing outstanding and often-aggressive flight manoeuvres, resilin can provide shock absorption against mechanical damage from strong impacts. It may further improve the wear and fatigue resistance owing to resilin's damping behaviour. Additionally, resilin in tendons can absorb and return kinetic energy to restore muscles to their original shape after contracting and help in maintaining self-oscillation of the flight muscles. Here, the material distribution within the direct flight system of Odonata and the biomechanical importance and possible function of resilin are discussed. These results are an important step towards the understanding of the complex form -material -function interplay of the insect cuticle.

The insect leg is a multifunctional device, varying tremendously in form and function within Insecta: from a common walking leg, to burrowing, swimming or jumping devices, up to spinning apparatuses or tools for prey capturing. Raptorial forelegs, as predatory striking and grasping devices, represent a prominent example for convergent evolution within insects showing strong morphological and behavioural adaptations for a lifestyle as an ambush predator. However, apart from praying mantises (Mantodea)—the most prominent example of this lifestyle—the knowledge on morphology, anatomy, and the functionality of insect raptorial forelegs, in general, is scarce. Here, we show a detailed morphological description of raptorial forelegs of Mantispa styriaca (Neuroptera), including musculature and the material composition in their cuticle; further, we will discuss the mechanism of the predatory strike. We could confirm all 15 muscles previously described for mantis lacewings, regarding extrinsic and intrinsic musculature, expanding it for one important new muscle—M24c. Combining the information from all of our results, we were able to identify a possible catapult mechanism (latch-mediated spring actuation system) as a driving force of the predatory strike, never proposed for mantis lacewings before. Our results lead to a better understanding of the biomechanical aspects of the predatory strike in Mantispidae. This study further represents a starting point for a comprehensive biomechanical investigation of the convergently evolved raptorial forelegs in insects.

Presenting your research in the proper light can be exceptionally challenging. Meanwhile, dome illumination systems became a standard for micro-and macrophotography in taxonomy, morphology, systematics and especially important in natural history collections. However, proper illumination systems are either expensive and/or laborious to use. Nowadays, 3D-printing technology revolutionizes lab-life and will soon find its way into most people's everyday life. Consequently, fused deposition modelling printers become more and more available, with online services offering personalized printing options. Here, we present a 3D-printed, scalable, low-cost and modular LED illumination dome system for scientific micro-and macrophotography. We provide stereolithography ('.stl') files and print settings, as well as a complete list of necessary components required for the construction of three differently sized domes. Additionally, we included an optional iris diaphragm and a sliding table, to arrange the object of desire inside the dome. The dome can be easily scaled and modified by adding customized parts, allowing you to always present your research object in the best light.