Damselflies are quintessential summer insects, so it is nice to see them on the wing again heralding the imminent approach of summer days.
Damselflies have long, slim bodies, two large, bulging eyes that are separated by a distinct gap and they seldom venture far from vegetation or the water surface of ponds and other water bodies.
They are a small group with just eleven species recorded in Ireland. All eleven are resident breeders. Mature males are easiest to identify as they are brightly coloured and boldly marked. Females and immature males are more difficult to identify as their colours can be very variable, often with several different colour forms.
The following key identifies the mature males of the eleven species. The first division is that two of the eleven species have coloured wings; the other nine have clear wings. The Beautiful Demoiselle has dark colour almost all over its wings whereas the Banded Demoiselle has just a large brown band, like a thumb-print, across the central portion of its wings.
The remaining nine have clear wings and are separated by the colour of the body: one is red, two are green and six are blue. The red one is the Large Red Damselfly pictured above. It has bright red eyes and a red body with some black markings. It is the only red damselfly found in Ireland and it is the first to emerge being on the wing in April. It is common and widespread.
Our two green members of the group are the Emerald Damselfly and the Scarce Emerald Damselfly. Both have some parts of the body coloured a metallic emerald green often with a bronzy sheen. They may also have some powdery blue markings. They are unusual among damselflies in that they rest with their wings spread out flat or partially so.
That leaves the six blues. Two of them are more black than blue but they have a striking patch of bright blue on their tails, so as 'blue-tails' they qualify as blues. The Blue-tailed Damselfly is more common and widespread than the local Scarce Blue-tailed Damselfly.
The remaining four are called 'bluets', and are more challenging to identify.
That said, many damselflies are relatively easy to identify using close-focusing binoculars. If you see a Large Red or other damselfly, Biodiversity Ireland would love to hear about it for their Dragonfly Ireland 2019-2024 monitoring scheme; full details and lots of helpful resources at https://www.biodiversityireland.ie/projects/monitoring-scheme-initiatives/dragonfly-ireland-2019-2024