The origin of microscopic spheres on the exoskeleton of the woodlouse Porcellionides pruinosus (Crustacea: Isopoda) and their effect on its hydrophobicity.

摘要: Abstract The dorsal surface of the woodlouse Porcellionides pruinosus is covered with minute spheres, providing its characteristic powdered appearance. Little has been known about their composition and formation. A previously suggested function these structures was to increase hydrophobicity cuticular surface. We studied ultrastructure, formation spheres as well tested whether they affect cuticle. determined histochemistry scanning electron microscopy after applying various chemicals. process transmission assessed cuticle by measuring contact angles water droplets Our results show that are largely organic. They contain proteins glycoproteins or possibly polysaccharides without detectable amounts lipids. By studying we established epicuticular structures. deposited early in premolt stage molt cycle around branching extensions epidermal cells. sphere-covered P. pruinosus more hydrophobic than experimentally removed scale-covered a related species.