Erythiagrion, a new genus of damselfly from Peru, with description of its type species Erythiagrion alidae (Odonata: Coenagrionidae)

Erythiagrion gen. n. is erected and Erythiagrion alidae sp. n. is described and illustrated. The genus Erythiagrion can be recognized morphologically by the following character combination: rounded frons, long abdomen (abdomen/HW length: 1.6–1.9), absence of pretarsal supplementary tooth and CuA ending at or within one cell distance of vein descending from subnodus. Additionally, males have a medial bifid process on posterior edge of both prothorax and S10 and an entirely yellow HW pterostigma bordered by a black spot. The general coloration of adults is black and bright yellow with a red abdominal tip.