The Dipsacaceae are a family with c. 300 species distributed in Eurasia with outposts in tropical and southern Africa. A peculiarity in fruits of this family is the occurrence of a cup-shaped tube or "epicalyx" that completely encloses the fruit (pericarp and seed). The epicalyx consists of four fused bracts that are highly differentiated within the family, especially in the derived genera Lomelosia, Pycnocomon, and Scabiosa. The calyx itself is either dehiscent in ripe fruits (Cephalaria, Dipsacus, Knautia), or modified into 4-5 spiny bristles (e.g., Lomelosia, Scabiosa, Succisa), or with bristles multiplied and plumose (Pterocephalus and partly so in other genera). Extreme differentiation of epicalyx and calyx in these genera prompted efforts to reveal their functions. Experimental studies suggest that during evolution of the family the epicalyx has become an important structure for protecting the developing fruits (s. str.), supporting fruit and seed development by in situ photosynthesis, facilitating fruit dispersal, and regulating germination.

Key words: accessory structures, Dipsacaceae, evolution, fruits, function