The Odonate fauna of Val Grande National Park (Insecta: Odonata)

Abstract

The results of a survey aimed at describing the Odonate fauna of Val Grande National Park are presented, which was carried out in the framework of the project “Animal Biodiversity Monitoring in Alpine Habitat”. Relevant literature was examined and data collected in- tensively in summer 2016 and extensively in the period 2014-2019. Prior to this research specific knowledge on dragonfly and damselfly presence and distribution accounted for 6 species for the study area, which were recorded near the northern border but outside the park. The first Odonate checklist here provided is based on 188 records (1173 individuals), of which 137 are recent and unpublished. Compre- hensively 25 species were recorded (14 breeding), which represent 26% of the Italian fauna, 36% of Piedmont and 58% of the province of Verbano Cusio Ossola, whereas three species were not confirmed; 10 species were found inside the park (4 breeding). Odonate diversity was remarkable, thanks to Val Grande geographical position between the Alps and the Insubric region and to high rainfall coupled with a complex orography. The study area hosts populations of the boreo-alpine species Somatochlora alpestris and Sympetrum danae, which are scattered and isolated in Italian Alps, and of the endemic European Cordulegaster bidentata; it hosts lotic taxa which are concentrat- ed in SW Europe where they are under pressure because of droughts and exploitation of freshwater. Conservation and status issues of observed dragonflies and damselflies are discussed in the light of the growing interest gained by odonates as ecological indicators. The study proposes to use this knowledge to guide the future expansions of the protected area.