A unique case of commensalism: The beaver beetle Platypsyllus castoris (Leiodidae, Coleoptera) and its morphological adaptations.

Platypsyllus castoris is closely associated with beavers and displays a unique set of structural specializations. We document the morphology of adults with modern techniques, and interpret evolutionary changes linked with the specific life style. The small subfamily Platypsyllinae has evolved an entire suite of features correlated with a more or less close association with mammals, for instance a flattened body, a dorsal cephalic shield, flightlessness, eye reduction, and depigmentation.

The locomotor apparatus of one of the smallest beetles - The thoracic skeletomuscular system of Nephanes titan (Coleoptera, Ptiliidae).

Pterothoracic structures of the minute ptiliid Nephanes titan were examined and described in detail. Effects of miniaturization and the phylogenetic and functional background are discussed. Apomorphies shared with Hydraenidae are the large metascutal shield, the fringe of setae along the posterior edge of the wings, and the fusion of the mesoventrite with the mesanepisternum.

A needle in a haystack: Mesozoic origin of parasitism in Strepsiptera revealed by first definite Cretaceous primary larva (Insecta).

Twisted winged insects (Strepsiptera) are a highly specialized small order of parasitic insects. Whether parasitism developed at an early or late stage in the evolution of the group was unknown. Here we record and describe the first Mesozoic strepsipteran primary larva embedded in Burmese amber (∼99 million years ago).

A review of methods for analysing insect structures - the role of morphology in the age of phylogenomics.

Techniques currently used in insect morphology are outlined briefly. Scanning electron microscopy (SEM) and microphotography are used mainly for documenting external features, the former providing more information on tiny surface structures and the latter on coloration, transparency and degree of sclerotization. A broad spectrum of methods is now available for anatomical studies: histological serial sections, confocal laser scanning microscopy (CLSM), light-sheet fluorescence microscopy (LSFM), serial block-face scanning electron microscopy (SBFSEM), dual beam scanning electron microscopy (FIB-SEM), nuclear magnetic resonance imaging (NMRI), and μ-computed tomography (micro-CT).

The head morphology of Clambidae and its implications for the phylogeny of Scirtoidea (Coleoptera: Polyphaga).

External and internal structures of the head of adults of Clambus are described and illustrated in detail. The results are compared with structural features found in the clambid genus Calyptomerus, in representatives of other scirtoid families, and also in species of other coleopteran suborders, notably Myxophaga. The results tentatively support the monophyly of Scirtoidea and a close relationship between Clambidae and Eucinetidae is suggested by one shared derived feature of the mandible, a long and slender apical tooth with a serrate edge.

Unique rostrate larvae and basidiomycophagy in the beetle family Corylophidae.

The head morphology of larvae of two undescribed species of the corylophid genus Holopsis were examined. Both are associated with the same basidiomycete host Ganoderma cf applanatum. Whereas the round and convex adults are very similar, one of the disc-shaped larvae is characterized by an elongate weevil-like snout, which is a unique feature in larval beetles.