The number of testicular follicles and ovarioles in Cicadomorpha (Hemiptera: Auchenorrhyncha): Variability and evolutionary trends

The hemipteran infraorder Cicadomorpha (cicadas, leafhoppers, treehoppers and spittlebugs) comprises more than 30,000 described extant species in 3,783 genera, 13 families and 3 superfamilies: Cicadoidea, Cercopoidea and Membracoidea. Here, we summarize and discuss data on the number of testicular follicles in 103 species belonging to 84 genera and 9 families of Cicadoidea (Tettigarctidae and Cicadidae), Cercopoidea (Aphrophoridae, Cercopidae and Ischnorhinidae) and Membracoidea (Aetalionidae, Cicadellidae, Membracidae and Myerslopiidae), as well as the number of ovarioles in 65 species belonging to 56 genera of the same families, except for Tettigarctidae, Aetalionidae, and Myerslopiidae, for which no such data were available. Almost 83% of the species and 81% of the genera studied belong to the family Cidadellidae. In general, the number of follicles in Cicadomorpha ranges from 1 to "about 100 or more" per testis, and the number of ovarioles from 3 to over 70-80 per ovary. The highest numbers are characteristic of Cicadoidea and Cercopoidea, with significantly higher values in the former superfamily. In Membracoidea, both follicle and ovariole numbers vary within markedly narrower limits. Most taxa are dominated by testes each consisting of 6 follicles, and the ovaries each consisting of 6 ovarioles. These character states are considered ancestral for Cicadomorpha, and possibly for Auchenorrhyncha as a whole.