Morphology and its relevance for systematics is a promising field for the application of biosemiotic principles in scientific practice. Genital coupling in spiders involves very complex interactions between the male and female genital structures. As exemplified by two spider species,Nephila clavipesandNephila pilipes ssp. fenestrata, from a biosemiotic point of view the microstructures of the male bulb’s embolus and the corresponding female epigynal and vulval parts form the morphological zone of an intraspecific communication and sign-interpreting process that is one of the (...) prerequisites for sperm transfer. Hence these morphological elements are of high taxonomic value, as they play an essential role in mating and fertilization and consequently in establishing and preserving a reproductive community. Morphology clearly benefits from a biosemiotic approach, as biosemiotics helps to sort out species-specific morphological characters and to avoid problematic typological interpretations. (shrink)