Éric Sardet is an entomologist who has specialised in orthoptera since the late 1990s. He works as an independent biologist with INSECTA, and is the author or co-author of a number of publications, including the red list of French orthoptera (published in collaboration with Bernard Defaut in 2004), and a departmental atlas of French orthoptera published in collaboration with Bernard Defaut and Yoan Braud in 2009 by l’Union de Entomologie Française. Christian Roesti has been interested in the orthoptera of Europe since the age of 6. He is the co-author of Sauterelles, Grillons et Criquets de Suisse and Die Stimmen der Heuschrecken, and co-creator of the smartphone app Orthoptera-App. He organises wildlife holidays, specialising in insects, and is equally enthusiastic about insect photography and scientific drawing. During summer, he works as a guard in a Swiss Alps nature reserve. Yoan Braud is an entomologist with a particular interest in the orthoptera of the Alps, Corsica and the Mediterranean region. He was the co-ordinator of the departmental atlas on French orthoptera (Defaut et al. 2009), and he’s currently working on the UICN red list for European orthoptera. Since 2014, he has been president of l’ASCETE (Association pour la Caractérisation de l’Étude des Entomocénoses). He works as an independent ecological entomologist with ENTOMIA.