Description of Calling, Courtship and Mating Behaviour of Six Species of the Genus (Auchenorrhyncha: Cicadellidae).

The vibrational communication and mating behaviour of the graminicolous leafhoppers , , , , , and were investigated to explain why the first five species hybridize. was used as a control species. All species behaved in the same way and no significant statistical differences were detected with regard to male calls, while female calls and the male courtship song differed in , thus showing that a specific pre-mating isolation mechanism was used by the latter species and the first five ones lacked such a mechanism. In addition, is missing in Italy, while the other species live allopatrically in Italy, with the only exceptions being and , which live in Sicily and are often found in sympatry, and and , which live in Sardinia. All these species can be distinguished by means of male genital appendages; however, is longer and has a different body colour. The existence of natural hybrids of , , and in the Italian peninsula and their hybridization in the laboratory with and require the investigation of possible post-mating reproductive barriers before re-considering their systematic validity.