Three-dimensional modelling in arachnology as exemplified using Porrhomma-species (Araneae: Linyphiidae)

Three-dimensional modelling has shown its importance in many fields, including zoological systematics. It is difficult to distinguish females of Porrhomma egeria Simon, 1884 and Porrhomma campbelli F. O. Pickard-Cambridge, 1894 according to only dorsal and ventral views of the vulva. The same is true for the pair Porrhomma microps (Roewer, 1931) and Porrhomma profundum Dahl, 1939. A caudal view is necessary to distinguish the vulvae of these species pairs. A 3D model combines all important views of the female genitalia (ventral, dorsal, lateral and caudal) into a single unit.