Cover photo by Diana Russell. Find this species in the FBIS database (Freshwater Biodiversity Information System) here. Family Libellulidae Identification Large size Length reaches 58mm; Wingspan attains 86mm. The Robust Skimmer is the largest Orthetrum species. Key identification features include long yellow pterostigmas, with a dark leading edge and broad dark brown shoulder patches on … Continue reading Robust Skimmer (Orthetrum robustum)