Species account

Western Willow Spreadwing (Chalcolestes viridis)    (Vander Linden, 1825)
   Spreadwings (Lestidae) [Dragonflies]    WWSP    24779
Grøn Kobbervandnymfe (dk)   Lestes Verdino (es)   Västlig Trädflickslända (se)  
Synonyms (common):
Willow Emerald Damselfly (gb) Lestes Sinople (es)
Synonyms (scientific):
Agrion leucopsallis Charpentier, 1825
Measurements:
To 39-48mm Ab 29-39mm Hw 23-28mm
Flight period:
JFMAMJJASOND 
Scan
EU
Identification:
Imago:
emerald green - narrow shoulder stripe - white wingmarks and male appendages
A large green-looking spreadwing with emerald green upperside and lime green lower side to the thorax. The abdomen is uniformly green above and pale greenish-beige underneath. The wing marks are long and white; with age they darken some. The eyes are maroon on top and pale green below and dark brown behind (they never turn blue). The thorax has a well-marked golden pale centerline on top as well as a pale shoulder stripe that stands out on the dark green background. On the side of the thorax there is a spur-like shape of the dark upper color entering into the paler limegreen lower part. In DK only this spreadwing species has it. The species does not tend to develop pruinosity with age, or at all, but it does darken in general also gaining the dark coppery look that is characteristic of the genus; also the eyes become all brownish with age. As the sexes are very similar they are mainly separated by their genitals and the appendages/ovipositors.

Male: The mature male upper appendages are mostly pale-white with an outer black edge running from the base to the tip; the tip is also black. They curve gently toward each other and reach at the tip. Along the inner edge there is a blunt dent two thirds from the base. The lower appendages are short (a fourth to a third length of the uppers), straight and black.

Female: The ovipositor is pale when young, but some parts become blackish when older, leaving a pied impression. The tip reaches the tip of S10, or slightly beyond. In close-up view 10+ tiny spikes, or dents, can be seen along the ventral distal ridge of the ovipositor [sometimes 9 might indicate a hybrid with parvides].
Similar species:
Chalcolestes parvidens - Lestes (sponsa, dryas, barbarus, virens)

  • Large like parvidens and barbarus and colored similarly bright green; virens small; sponsa and dryas tendency to pruinosity.

  • Spur-like shape on thorax side only seen on parvidens.

  • Complete white wing marks unique to viridis (young parvidens and Lestes species can show as well, normally brown colors and barbarus always two colored brown-white); parvidens wing marks on forewings shifted more toward tip than on hindwings.

  • Male upper appendages (cerci) most similar to parvidens and barbarus; on parvidens white with limited black tip, more black on viridens; inside pale dent on viridis almost absent on parvidens; on barbarus black tip and inner curve; other Lestes species generally all dark/black. Male lower appendages (paraprocts) most similar to parvidens and virens: short, black and straight. Long dark on sponsa and L. dryas; short diverting pale on barbarus.

  • Ovipositor color changeable as on similar species; same length on most species but dryas extends beyond tip of S10; parvidens ovipositor has less than 9 spikes (viridis > 9) along the ventral distal ridge [hybrids might have 9].

  • Eye color not turning blue with age as on Lestes species.

  • Water-side habitat edged with trees and bushes only shared by parvidens.

Life stages:
Females, in tandem, insert eggs into living plant material overhanging the water. Eggs overwinter and larvae develop to imago in 2-3 months. The imago-transformation takes place near the water low on the vegetation.
Distribution:
Most of W, C and S Europe. Also N Africa; Absent Scandinavian peninsula and most of British isles. In S and E Europe it overlaps with parvidens why it is not well-defined where the exact eastern limit of the species's range goes.
Habitat:
Permanent standing or slow-moving waters bordered by brush vegetation or trees from where branches overhang the water. Both natural and cultivated landscapes.
Behavior:
When not in breeding mode both sexes like to hang from twigs and leaves in bushes and trees, often a distance from the breeding water. They can sit several meters above the ground, unlike the lestes species. When ready to drop her eggs the female uses the saw-like spikes on the ovipositor to make an incision into the soft bark of twigs overhanging the water where she inserts the eggs. When ready the pro-larvae drop directly into the water. The bark incisions can be seen as permanent scars years later.
Host plants:
Willows (Salix)
Other water side bushes and trees.
Endemic:
Status
In DK first found in southern Jylland in 2005, and now expanding rapidly north through the peninsula to Limfjorden (2023) and also eastward across Fyn to the eastern border(Nyborg).
Comment:
-Flight period is increasing in Denmark now with the species also being seen in small numbers into November.
-Overlap with parvidens in Italy and northern Balkans.
Mature male
Mature female

Mature female
Immature male - pale bright colors

Mature male appendages
Western Willow Spreadwing 2064    (1 photos)
2023-07-27    Ny Sebberup Skov (Hedensted), Denmark

Imago Male




Western Willow Spreadwing 2065    (1 photos)
2023-07-27    Ny Sebberup Skov (Hedensted), Denmark

Imago Male




Western Willow Spreadwing 2066    (3 photos)
2023-07-27    Ny Sebberup Skov (Hedensted), Denmark

Imago Male
Not always showing its name-giving behavior...tightwing...



Western Willow Spreadwing 2062    (2 photos)
2023-07-27    Ny Sebberup Skov (Hedensted), Denmark

Imago Male




Western Willow Spreadwing 2153    (2 photos)
2023-08-05    Ny Sebberup Skov (Hedensted), Denmark

Imago Male
Defecating.



Western Willow Spreadwing 2155    (2 photos)
2023-08-05    Ny Sebberup Skov (Hedensted), Denmark

Imago Male




Western Willow Spreadwing 2156    (1 photos)
2023-08-05    Ny Sebberup Skov (Hedensted), Denmark

Imago Male




Western Willow Spreadwing 2158    (1 photos)
2023-08-05    Ny Sebberup Skov (Hedensted), Denmark

Imago Male




Western Willow Spreadwing 2159    (1 photos)
2023-08-05    Ny Sebberup Skov (Hedensted), Denmark

Imago Male




Western Willow Spreadwing 2063    (3 photos)
2023-07-27    Ny Sebberup Skov (Hedensted), Denmark

Imago Female
Spreadwings collapse their wings when going to rest or, as I think is the case here, they feel threatened or at least stressed. I did chase this animal for a while, being my first female ever of the species, I probably got too excited.



Western Willow Spreadwing 2157    (1 photos)
2023-08-05    Ny Sebberup Skov (Hedensted), Denmark

Imago Female




Western Willow Spreadwing 2166    (1 photos)
2023-08-05    Ny Sebberup Skov (Hedensted), Denmark

Imago Female




Western Willow Spreadwing 2165    (3 photos)
2023-08-05    Ny Sebberup Skov (Hedensted), Denmark

Imago Female




Western Willow Spreadwing 2164    (2 photos)
2023-08-05    Ny Sebberup Skov (Hedensted), Denmark

Imago Female
Do they sit like this with the wings held together on one side of the body like the winter damsels, or is it perhaps a sign of stress?



Western Willow Spreadwing 2163    (3 photos)
2023-08-05    Ny Sebberup Skov (Hedensted), Denmark

Imago Female




Western Willow Spreadwing 2162    (1 photos)
2023-08-05    Ny Sebberup Skov (Hedensted), Denmark

Imago Female




Western Willow Spreadwing 2161    (2 photos)
2023-08-05    Ny Sebberup Skov (Hedensted), Denmark

Imago Female




Western Willow Spreadwing 2160    (1 photos)
2023-08-05    Ny Sebberup Skov (Hedensted), Denmark

Imago Female




Western Willow Spreadwing 2152    (1 photos)
2023-08-05    Ny Sebberup Skov (Hedensted), Denmark

Imago Female




Western Willow Spreadwing 3041    (3 photos)
2024-08-30    Bygholmparken (Horsens), Denmark

Imago Female
3 different females.
I didn't have time to search the park properly, why I only managed to find these 3 animals. The park has a lot of canals and lakes with overhanging branches and foliage making it ideal for the species.




Western Willow Spreadwing 2154    (2 photos)
2023-08-05    Ny Sebberup Skov (Hedensted), Denmark

Imago Male & Female
Just two animals close to each other without interaction.