'Blue Damselflies' around Granta Park

13th July 2025 - there were a good few damselflies around GP, and Andy M picked out both Common Blue Damselfly and Blue-tailed Damselfly around the lake. Both have a basically pale blue head and thorax, with black markings. The abdomen (tail) of the the Common Blue Damselfly is basically all blue with regular black stripes down the length, whereas the Blue-tailed Damselfly abdomen is basically black with a blue tip. 

Interestingly, there are several forms of female Blue-tailed Damselfly; the more usual typica form looks much like the male, but also seen around the lake were the violacea form, in which the thorax starts violet in the immature, turning olive-green in the adult with the blue tip to the abdomen turning brown.

Andy also spotted a Red-eyed Damselfly resting on a lily pad, as is typical for this species. Superficially, this is similar to a Blue-tailed Damselfly in terms of having a largely blue thorax, and a dark abdomen with a blue end. However, as its name suggests, it has characteristic ruby-red eyes.

Common Blue Damselfly - largely blue abdomen, with black stripes

Common Blue Damselfly

Common Blue Damselfly

Male / Female typica Blue-tailed Damselfly

Female immature violacea Blue-tailed Damselfly 

Mating pair of Blue-tailed Damselfly

(male above, mature female violacea below)

Red-eyed Damselfly