The identification and recognition of the about 60 bumblebee species occurring in Europe is considered difficult. There are only few useful morphological characteristics and the determination by the often striking coat coloration is very unreliable, mainly because of the great variability of this coloration in many species. The conspicuously formed genital capsule of the males offers the beginner many useful characteristics and an easy possibility to separate the many species into about 16 species groups - subgenera. Both the preparation and the examination of the genital capsule are considered difficult. The main obstacles in the use of these characteristics of the genital capsule are (1) the delimitation of the parts of a genital capsule, and (2) the recognition of these complicated three-dimensional structures.

With a little patience and skill, even the beginner will be able to study these features and use them successfully after a short time. Good illustrations make it easier to find the characteristics of these rather small structures and a simple text explains to beginners how to work with genital capsules. In the introduction presented here, the color coding of the various sclerites makes it easier for beginners to distinguish between them and to recognize the shapes through 3D images. With 116 SEM images (Raster Electron Microscope) of 29 selected species, the 16 subgenera occurring in Europe are presented (most of them in at least 2 species).