De blauwoogjuffer: Waarom “Cercion” eigenlijk Erythromma lindenii moet heten

Weekers & Dumont (2004) proved through molecular studies what Heidemann & Seidenbusch (1993) already suggested by larval characters: Cercion is a synonym of Erythromma. Compared to European Coenagrion and Enallagma species, Erythromma with the inclusion of E. lindenii differs by: (1) Numerous bristles on the larval sternites. (2) Similarities in DNA. (3) Elongated cerci with bifid tip and large basal tooth; paraprocts reduced to small points. (4) Subcostal cells distal of pterostigma often duplicated, especially in hindwing. (5) Reduced postocular spots. (6) Completely black dorsum of abdominal segment 2. (7) Blue abdominal ‘tail-light’ shifted distally to segments 9-10. (8) Eyes brightly coloured without blackish dorsum, contrasting with black dorsum of head. (9) Reproductive activity on emergent and floating vegetation away from the shore. The blue body and eyes of lindenii possibly represent a reversal to a plesiomorphic character state. This relatively minor difference with other Erythromma species has led to the traditional association of E. lindenii with taxa that are merely superficially similar (like Coenagrion) and the oversight of its true identity.